Table of Contents

Summary Information	3
Additional Information on the Fund's Investment Objective and Strategies	10
Fund Investments	10
Additional Risks of Investing in the Fund	13
Fund Organization	17
Management of the Fund	17
How to Buy and Sell Shares	18
Dividends, Distributions and Taxes	20
Federal Tax Matters	20
Distribution Plan	22
Net Asset Value	22
Fund Service Providers	24
Premium/Discount Information	24
Total Return Information	24
Financial Highlights	26
Other Information	27

Investment Objective

The First Trust Enhanced Short Maturity ETF's (the " Fund ") investment objective is to seek current income, consistent with preservation of capital and daily liquidity.

Fees and Expenses of the Fund

The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund. Investors purchasing and selling shares may be subject to costs (including customary brokerage commissions) charged by their broker, which are not reflected in the table below.

Shareholder Fees
(fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

None

    

(1)

Although the Fund has adopted a 12b-1 plan that permits it to pay up to 0.25% per annum, it will not pay 12b-1 fees at any time before March 31, 2019.

(2)

Pursuant to a contractual agreement, First Trust Advisors L.P., the Fund's investment advisor, has agreed to waive management fees of 0.10% of average daily net assets until March 1, 2019. This waiver agreement may be terminated by action of the Trust's Board of Trustees at any time upon 60 days' written notice by the Trust on behalf of the Fund or by the Fund's investment advisor only after March 1, 2019.

(3)

Pursuant to a contractual agreement between the Trust, on behalf of the Fund, and First Trust Advisors L.P., the Fund’s investment advisor, the management fees paid to the Fund’s investment advisor will be reduced by the portion of the management fees earned by the Fund’s investment advisor from the Fund for assets invested in other investment companies advised by the Fund’s investment advisor. This contractual agreement shall continue until the earlier of (i) its termination at the direction of the Trust’s Board of Trustees or (ii) upon the termination of the Fund’s management agreement with the Fund’s investment advisor, however, it is expected to remain in place for no less than one year from the date of this prospectus.

(4)	Fee Waiver has been restated to reflect the current fiscal year.

Example

The example below is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. This example does not take into account customary brokerage commissions that you pay when purchasing or selling shares of the Fund in the secondary market.

The example assumes that you invest $10,000 in the Fund for the time periods indicated. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses, excluding acquired fund fees and expenses, remain (i) at current levels until March 1, 2019, (ii) at 0.45% from March 1, 2019 to March 31, 2019, and (iii) thereafter at 0.70% to represent the imposition of the 12b-1 fee of 0.25% per annum of the Fund’s average daily net assets. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

1 Year	3 Years	5 Years	10 Years
$36	$186	$353	$835

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 56% of the average value of its portfolio.

3

Table of Contents

Summary Information	3
Additional Information on the Fund's Investment Objective and Strategies	10
Fund Investments	10
Additional Risks of Investing in the Fund	11
Fund Organization	15
Management of the Fund	15
How to Buy and Sell Shares	17
Dividends, Distributions and Taxes	18
Federal Tax Matters	18
Distribution Plan	20
Net Asset Value	21
Fund Service Providers	21
Premium/Discount Information	21
Total Return Information	22
Financial Highlights	24
Other Information	25

Investment Objectives

The First Trust Heitman Global Prime Real Estate ETF's (the "Fund" ) investment objective is to provide long-term total return.

Fees and Expenses of the Fund

The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund. Investors purchasing and selling shares may be subject to costs (including customary brokerage commissions) charged by their broker, which are not reflected in the table below.

Shareholder Fees
(fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

None

    

Annual Fund Operating Expenses
(expenses that you pay each year as a percentage of the value of your investment)

Management Fees	0.95%
Distribution and Service (12b-1) Fees (1)	0.00%
Other Expenses	0.00%
Total Annual Fund Operating Expenses	0.95%

(1)	Although the Fund has adopted a 12b-1 plan that permits it to pay up to 0.25% per annum, it will not pay 12b-1 fees at any time before March 31, 2019.

Example

The example below is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. This example does not take into account customary brokerage commissions that you pay when purchasing or selling shares of the Fund in the secondary market.

The example assumes that you invest $10,000 in the Fund for the time periods indicated. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain at current levels until March 31, 2019, and thereafter at 1.20% to represent the imposition of the 12b-1 fee of 0.25% per annum of the Fund’s average daily net assets. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

1 Year	3 Years	5 Years	10 Years
$97	$356	$636	$1,432

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 104% of the average value of its portfolio.

Principal Investment Strategies

Under normal market conditions, the Fund will seek to achieve its investment objective by investing at least 80% of its net assets (including investment borrowings) in U.S. and non-U.S. exchange-traded real estate securities, which includes real estate investment trusts ( “REITs” ), real estate operating companies ( “REOCs” ) and common stocks or depositary receipts of companies primarily engaged in the real estate industry (collectively, “Real Estate Securities” ). Accordingly, the Fund is concentrated in REITs and/or real estate management and development companies (including REOCs), sub-industries of the real estate industry group. Real estate management and development companies generally derive at least 50% of their revenue from, or have at least 50% of their assets invested in, real estate, including the ownership, construction, management, or sale of real estate. The Fund will not invest directly in real estate.

3

The Fund seeks to provide investors access to a real estate securities portfolio consisting of shares of public companies with professional management teams that own top-tier, prime properties in the world’s dominant cities. “Prime” markets and cities are some of the world’s top cities which are recognized as “global gateway” markets that benefit from global physical and/or financial trade, have high barriers to entry, dominate their regions or countries, or provide high value niche goods and services. The key factors are location, physical specification, sustainability, tenant quality, and income stability. In practice, prime assets are also ones that are competitively sought after and command high values in both absolute and relative terms, resulting in relatively low cap rates.

The Fund’s portfolio managers will select Real Estate Securities by implementing an investment process that is outlined below:

As a first screen, all securities in the Global Industry Classification Standard ( GICS ^® ) real estate industry are filtered for size and liquidity, based upon free float market capitalization for size and a threshold daily trading volumes for liquidity. The purpose of these quantitative screens is to ensure that the investment strategy can be executed in a buy and hold manner without undue stress.

In the second stage, screening is conducted using a combination of qualitative and quantitative tools. From a qualitative perspective, portfolio analysts maintain a close coverage universe and are in regular contact with the management of potential Real Estate Securities issuers, regularly visiting properties and markets to see as many of the properties in person as is reasonably possible. In addition to their own research, the analysts have access to other property experts and sell-side professionals within their organizations who also evaluate their companies. The task of the analysts is to identify those companies that meet the test of two quantitative filters. The issuers in which the Fund invests must generally have (1) more than 75% of their gross asset value in prime markets and (2) more than 50% of their assets under management in prime assets.

Executing the quantitative and qualitative screens produces a universe of companies that meet the size, liquidity, and concentration in prime markets and assets tests. From this universe of prime assets and markets, the portfolio managers’ regional teams construct a high conviction portfolio that, in the opinion of the portfolio managers, offers the best expected risk/return profile of the names within the prime universe. Consideration for inclusion in the portfolio includes the issuer’s balance sheet, assessment of management’s acumen and the projected long-term growth profile of the company.

The Fund invests in REITs and REOCs which are companies that own and most often actively manage income-generating commercial real estate. REITs distribute most of their income to investors and therefore receive special tax considerations and are typically a highly liquid method of investing in real estate. REOCs, on the other hand, reinvest most income into their operations and therefore do not get the same benefits of lower corporate taxation that are a common characteristic of REITs.

The Fund typically invests in 25 to 100 Real Estate Securities issued by small, mid and large capitalization companies. The Fund invests in securities of issuers domiciled or operating in Asia and Europe, as well as other non-U.S. issuers, including those in emerging market countries. The Fund intends to invest at least 40% of its net assets in securities of non-U.S. issuers and in issuers domiciled or operating in at least three different countries.

The Fund is classified as “non-diversified” under the Investment Company Act of 1940, as amended (the “1940 Act” ) and as a result may invest a relatively high percentage of its assets in a limited number of issuers. The Fund is only limited as to the percentage of its assets which may be invested in the securities of any one issuer by diversification requirements imposed by the Internal Revenue Code of 1986, as amended.

Principal Risks

You could lose money by investing in the Fund. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. There can be no assurance that the Fund’s investment objective will be achieved.

ASIA INVESTMENT RISK. The Fund invests, in part, in securities issued by companies operating in Asia, and is therefore subject to certain risks associated specifically with Asia. For example, some of the currencies of these countries , including China, have experienced devaluations relative to the U.S. dollar, and adjustments have been made periodically in certain of such currencies. Certain countries, such as Indonesia, face serious exchange constraints. Jurisdictional disputes also exist, for example, between South Korea and North Korea. The Tokyo stock market, as measured by the Tokyo Stock Price Index, has been volatile. Declines in the Tokyo stock market have made the country’s banks and financial institutions vulnerable. Furthermore, the natural disasters that have impacted Japan and the ongoing recovery efforts have had a negative affect on Japan’s economy, and may continue to do so.

4

AUTHORIZED PARTICIPANT CONCENTRATION RISK. Only an authorized participant (as defined in the “Frequent Purchases and Redemptions” Section) may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of institutions that act as authorized participants. To the extent that these institutions exit the business or are unable to proceed with creation and/or redemption orders with respect to the Fund and no other authorized participant is able to step forward to create or redeem, in either of these cases, Fund shares may trade at a discount to the Fund’s net asset value and possibly face delisting.

CONCENTRATION RISK. The Fund is concentrated in REITs and/or real estate management and development companies. A fund concentrated in one or more sectors, industries or groups of industries is likely to present more risks than a fund that is broadly diversified over several industries or sectors. Compared to the broad market, an individual industry or sector may be more strongly affected by changes in the economic climate, broad market shifts, moves in a particular dominant stock, or regulatory changes.

CURRENCY RISK. The Fund may hold investments that are denominated in non-U.S. currencies, or in securities that provide exposure to such currencies, currency exchange rates or interest rates denominated in such currencies. Changes in currency exchange rates and the relative value of non-U.S. currencies will affect the value of the Fund’s investments and the value of Fund shares. Currency exchange rates can be very volatile and can change quickly and unpredictably. As a result, the value of an investment in the Fund may change quickly and without warning and you may lose money.

CYBER SECURITY RISK. As the use of Internet technology has become more prevalent in the course of business, the Fund has become more susceptible to potential operational risks through breaches in cyber security. A breach in cyber security refers to both intentional and unintentional events that may cause the Fund to lose proprietary information, suffer data corruption or lose operational capacity. Such events could cause the Fund to incur regulatory penalties, reputational damage, additional compliance costs associated with corrective measures and/or financial loss. Cyber security breaches may involve unauthorized access to the Fund’s digital information systems through “hacking” or malicious software coding, but may also result from outside attacks such as denial-of-service attacks through efforts to make network services unavailable to intended users. In addition, cyber security breaches of the Fund’s third party service providers, such as its administrator, transfer agent, custodian, or sub-advisor, as applicable, or issuers in which the Fund invests, can also subject the Fund to many of the same risks associated with direct cyber security breaches. The Fund has established risk management systems designed to reduce the risks associated with cyber security. However, there is no guarantee that such efforts will succeed, especially because the Fund does not directly control the cyber security systems of issuers or third party service providers.

DEPOSITARY RECEIPTS RISK. Depositary receipts may be less liquid than the underlying shares in their primary trading market. Any distributions paid to the holders of depositary receipts are usually subject to a fee charged by the depositary. Holders of depositary receipts may have limited voting rights, and investment restrictions in certain countries may adversely impact the value of depositary receipts because such restrictions may limit the ability to convert the equity shares into depositary receipts and vice versa. Such restrictions may cause the equity shares of the underlying issuer to trade at a discount or premium to the market price of the depositary receipts.

EMERGING MARKETS RISK. Investments in securities of issuers located in emerging market countries are considered speculative. Heightened risks of investing in emerging markets securities include: (i) smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; (ii) significant price volatility; (iii) restrictions on foreign investment; and (iv) possible repatriation of investment income and capital. Furthermore, foreign investors may be required to register the proceeds of sales and future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Fund. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.

EQUITY SECURITIES RISK. Because the Fund invests in equity securities, the value of the Fund’s shares will fluctuate with changes in the value of these equity securities. Equity securities prices fluctuate for several reasons, including changes in investors’ perceptions of the financial condition of an issuer or the general condition of the relevant stock market, such as market volatility, or when political or economic events affecting the issuers occur. In addition, common stock prices may be particularly sensitive to rising interest rates, as the cost of capital rises and borrowing costs increase.

EUROPE INVESTMENT RISK. Investments in a single region, even though representing a number of different countries within the region, may be affected by common economic forces and other factors. The Fund is subject to greater risks of adverse events which occur in the European region and may experience greater volatility than a fund that is more broadly diversified

5

geographically. Political or economic disruptions in European countries, even in countries in which the Fund is not invested, may adversely affect security values and thus the Fund’s holdings. Continuing uncertainty as to the status of the Euro and the European Monetary Union and the potential for certain countries to withdraw from the institution has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the European Union could have significant adverse effects on currency and financial markets, and on the values of a Fund’s portfolio investments.

FLUCTUATION OF NET ASSET VALUE RISK . The net asset value of shares of the Fund will generally fluctuate with changes in the market value of the Fund’s holdings. The market prices of shares will generally fluctuate in accordance with changes in net asset value as well as the relative supply of and demand for shares on the Exchange. The Fund’s investment advisor cannot predict whether shares will trade below, at or above their net asset value because the shares trade on the Exchange at market prices and not at net asset value. Price differences may be due, in large part, to the fact that supply and demand forces at work in the secondary trading market for shares will be closely related to, but not identical to, the same forces influencing the prices of the holdings of the Fund trading individually or in the aggregate at any point in time. However, given that shares can only be purchased and redeemed either in-kind or for cash in Creation Units, and only to and from broker-dealers and large institutional investors that have entered into participation agreements (unlike shares of closed-end funds, which frequently trade at appreciable discounts from, and sometimes at premiums to, their net asset value), the Fund’s investment advisor believes that large discounts or premiums to the net asset value of shares should not be sustained.

INTEREST RATE RISK. Increases in interest rates typically coincide with higher investor required returns and can lower the present value of a REIT’s future earnings stream if not met with a commensurate increase in growth.

MANAGEMENT RISK. The Fund is subject to management risk because it is an actively managed portfolio. In managing the Fund’s investment portfolio, the Fund’s portfolio managers will apply investment techniques and risk analyses that may not have the desired result. There can be no guarantee that the Fund will meet its investment objective.

MARKET MAKER RISK. If the Fund has lower average daily trading volumes, it may rely on a small number of third-party market makers to provide a market for the purchase and sale of shares. Any trading halt or other problem relating to the trading activity of these market makers could result in a dramatic change in the spread between the Fund’s net asset value and the price at which the Fund’s shares are trading on the Exchange which could result in a decrease in value of the Fund’s shares. In addition, decisions by market makers or authorized participants to reduce their role or step away from these activities in times of market stress could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the underlying values of the Fund’s portfolio securities and the Fund’s market price. This reduced effectiveness could result in Fund shares trading at a discount to net asset value and also in greater than normal intraday bid-ask spreads for Fund shares.

MARKET RISK. Market risk is the risk that a particular security owned by the Fund or shares of the Fund in general may fall in value. Securities are subject to market fluctuations caused by such factors as economic, political, regulatory or market developments, changes in interest rates and perceived trends in securities prices. Overall Fund share values could decline in value or underperform other investments.

NON-DIVERSIFICATION RISK. The Fund is classified as “non-diversified” under the 1940 Act. As a result, the Fund is only limited as to the percentage of its assets which may be invested in the securities of any one issuer by the diversification requirements imposed by the Internal Revenue Code of 1986, as amended. The Fund may invest a relatively high percentage of its assets in a limited number of issuers. As a result, the Fund may be more susceptible to a single adverse economic or regulatory occurrence affecting one or more of these issuers, experience increased volatility and be highly invested in certain issuers.

NON-U.S. SECURITIES RISK. The Fund may invest in securities of non-U.S. issuers. Non-U.S. securities are subject to higher volatility than securities of domestic issuers due to possible adverse political, social or economic developments, restrictions on foreign investment or exchange of securities, lack of liquidity, currency exchange rates, excessive taxation, government seizure of assets, different legal or accounting standards, and less government supervision and regulation of exchanges in foreign countries.

PORTFOLIO TURNOVER RISK. The Fund’s strategy may frequently involve buying and selling portfolio securities to rebalance the Fund’s exposure to various market sectors. High portfolio turnover may result in the Fund paying higher levels of transaction costs and generating greater tax liabilities for shareholders. Portfolio turnover risk may cause the Fund’s performance to be less than you expect.

REAL ESTATE INVESTMENT RISK. The Fund invests in companies in the real estate industry, including REITs and REOCs. Therefore, the Fund is subject to the risks associated with investing in real estate, which may include, but are not limited to,

6

fluctuations in the value of underlying properties; defaults by borrowers or tenants; market saturation; changes in general and local economic conditions; decreases in market rates for rents; increases in competition, property taxes, capital expenditures or operating expenses; and other economic, political or regulatory occurrences affecting companies in the real estate industry.

REIT INVESTMENT RISK. In addition to risks related to investments in real estate generally, investing in REITs involves certain other risks related to their structure and focus, which include, but are not limited to, dependency upon management skills, limited diversification, the risks of locating and managing financing for projects, heavy cash flow dependency, possible default by borrowers, the costs and potential losses of self-liquidation of one or more holdings, the risk of a possible lack of mortgage funds and associated interest rate risks, overbuilding, property vacancies, increases in property taxes and operating expenses, changes in zoning laws, losses due to environmental damages, changes in neighborhood values and appeal to purchasers, the possibility of failing to maintain exemptions from registration under the 1940 Act and, in many cases, relatively small market capitalization, which may result in less market liquidity and greater price volatility. REITs are also subject to the risk that the real estate market may experience an economic downturn generally, which may have a material effect on the real estate in which the REITs invest and their underlying portfolio securities.

SMALL FUND RISK. The Fund currently has fewer assets than larger funds, and like other relatively smaller funds, large inflows and outflows may impact the Fund’s market exposure for limited periods of time. This impact may be positive or negative, depending on the direction of market movement during the period affected.

SMALLER COMPANIES RISK. Small and/or mid capitalization companies may be more vulnerable to adverse general market or economic developments, and their securities may be less liquid and may experience greater price volatility than larger, more established companies as a result of several factors, including limited trading volumes, products or financial resources, management inexperience and less publicly available information. Accordingly, such companies are generally subject to greater market risk than larger, more established companies.

TRADING ISSUES RISK . Although the shares of the Fund are listed for trading on the Exchange, there can be no assurance that an active trading market for such shares will develop or be maintained. Trading in shares on the Exchange may be halted due to market conditions or for reasons that, in the view of the Exchange, make trading in shares inadvisable. In addition, trading in shares on the Exchange is subject to trading halts caused by extraordinary market volatility pursuant to the Exchange’s “circuit breaker” rules. Market makers are under no obligation to make a market in the Fund’s shares, and authorized participants are not obligated to submit purchase or redemption orders for Creation Units. There can be no assurance that the requirements of the Exchange necessary to maintain the listing of the Fund will continue to be met or will remain unchanged. In particular, if the Fund does not comply with any provision of the listing standards of the Exchange that are applicable to the Fund, and cannot bring itself into compliance within a reasonable period after discovering the matter, the Exchange may remove the shares of the Fund from listing. The Fund may have difficulty maintaining its listing on the Exchange in the event the Fund's assets are small or the Fund does not have enough shareholders.

Annual Total Return

The bar chart and table below illustrate the annual calendar year returns of the Fund based on net asset value as well as the average annual Fund returns. The bar chart and table provide an indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year-to-year and by showing how the Fund’s average annual total returns based on net asset value compared to those of a broad-based securities market index. See “Total Return Information” for additional performance information regarding the Fund. The Fund’s performance information is accessible on the Fund’s website at www.ftportfolios.com.

Returns before taxes do not reflect the effects of any income or capital gains taxes. All after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of any state or local tax. Returns after taxes on distributions reflect the taxed return on the payment of dividends and capital gains. Returns after taxes on distributions and sale of shares assume you sold your shares at period end, and, therefore, are also adjusted for any capital gains or losses incurred. Returns for the market indices do not include expenses, which are deducted from Fund returns, or taxes.

Your own actual after-tax returns will depend on your specific tax situation and may differ from what is shown here. After-tax returns are not relevant to investors who hold Fund shares in tax-deferred accounts such as individual retirement accounts ( IRAs ) or employee-sponsored retirement plans.

7

First Trust Advisors L.P. ( “First Trust” or the “Advisor” )

Investment Sub-Advisor

Heitman Real Estate Securities LLC ( “HRES LLC” or the “Sub-Advisor” )

Investment Sub-Sub-Advisors

Heitman International Real Estate Securities HK Limited ( “Heitman HK Limited” or a “Sub-Sub-Advisor” )
Heitman International Real Estate Securities GmbH ( “Heitman GmbH” or a “Sub-Sub-Advisor” )

Portfolio Managers

The following persons serve as the portfolio managers of the Fund.

•	Jerry Ehlinger, CFA, Managing Director of HRES LLC and Lead Portfolio Manager in the North American Public Real Estate Securities group;

•	John White, Managing Director of Heitman HK Limited and Lead Portfolio Manager in the Asia-Pacific Public Real Estate Securities group;

•	Jacques Perdrix, Senior Vice President of HRES LLC’s European Public Real Estate Securities group; and
•	Andreas Welter, Senior Vice President of HRES LLC’s European Public Real Estate Securities group.

8

The portfolio managers are primarily and jointly responsible for the day-to-day management of the Fund. Each portfolio manager has served as part of the portfolio management team of the Fund since 2015, except for Jacques Perdrix and Andreas Welter, who have served as part of the portfolio management team of the Fund since 2017.

Purchase and Sale of Fund Shares

The Fund issues and redeems shares on a continuous basis, at net asset value, only in Creation Units consisting of 50,000 shares. The Fund’s Creation Units are generally issued and redeemed in-kind for securities in which the Fund invests and, in certain circumstances, for cash, and only to and from broker-dealers and large institutional investors that have entered into participation agreements. Individual shares may only be purchased and sold on NYSE Arca and other eligible securities exchanges through a broker-dealer. Shares of the Fund will trade on NYSE Arca at market prices rather than net asset value, which may cause the shares to trade at a price greater than net asset value (premium) or less than net asset value (discount).

Tax Information

The Fund’s distributions are taxable and will generally be taxed as ordinary income or capital gains. Distributions on shares held in a tax deferred account, while not immediately taxable, will be subject to tax when the shares are no longer held in a tax deferred account.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase shares of the Fund through a broker-dealer or other financial intermediary (such as a bank), First Trust and First Trust Portfolios L.P., the Fund’s distributor, may pay the intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.

9

Additional Information on the Fund's Investment Objective and Strategies

The Fund’s investment objective is fundamental and may not be changed without approval by the holders of a majority of the outstanding voting securities of the Fund. Unless an investment policy is identified as being fundamental, all investment policies included in this prospectus and the Fund’s Statement of Additional Information ( “SAI” ) are non-fundamental and may be changed by the Board of Trustees (the “Board” ) of First Trust Exchange-Traded Fund IV (the “Trust” ), of which the Fund is a series, without shareholder approval.

The Fund has adopted a non-fundamental investment policy pursuant to Rule 35d-1 under the 1940 Act (the “Name Policy” ) whereby the Fund, under normal market conditions, invests at least 80% of its net assets (including investment borrowings) in Real Estate Securities. The Name Policy may be changed by the Board of Trustees without shareholder approval upon 60 days’ prior written notice.

The portfolio managers will select Real Estate Securities by combining top-down and bottom-up analysis while acknowledging the sensitivity of real estate stocks to local equity market fluctuations and momentum. The strategy seeks to provides investors access to a professionally managed real estate securities portfolio consisting of shares of public companies that own top-tier, prime properties in the world’s dominant cities, have strong balance sheets and have additional diversification of debt and equity funding sources at favorable rates. If there is a material change to the Fund’s principal investment strategies, you should consider whether the Fund remains an appropriate investment for you. There is no guarantee that the Fund will achieve its investment objective. During the initial invest-up period, the Fund may depart from its principal investment strategies and invest a larger amount or all of its assets in cash or cash equivalents.

Fund Investments

Principal Investments

REITs and REOCs

The Fund invests in REITs and REOCs which are companies that own and most often actively manage income-generating commercial real estate. Some REITs and REOCs make or invest in loans and other obligations that are secured by real estate collateral. REITs distribute most of their income to investors and therefore receive special tax considerations and are typically a highly liquid method of investing in real estate. REOCs, on the other hand, reinvest most income into their operations and therefore do not get the same benefits of lower corporate taxation that are a common characteristic of REITs.

REITs and REOCs are generally categorized as equity, mortgage or hybrid in nature. Equity REITs and REOCs invest in and own properties, and thus are responsible for the equity or value of their real estate assets. Their revenues come principally from their properties’ rents. Mortgage REITs and REOCs deal in investment and ownership of property mortgages. These companies loan money for mortgages to owners of real estate or purchase existing mortgages or mortgage-backed securities. Their revenues are generated primarily by the interest that they earn on the mortgage loans. Hybrid REITs and REOCs combine the investment strategies of equity REITs and REOCs and mortgage REITs and REOCs by investing in both properties and mortgages.

Equity Securities

The Fund invests in equity securities of companies primarily engaged in the real estate industry, including REITs and REOCs.

Non-U.S. Investments

The Fund may invest in securities issued by non-U.S. companies that are traded over-the-counter or listed on an exchange or in the form of depositary receipts. Non-U.S. investments include securities issued or guaranteed by companies organized under the laws of countries other than the United States, including companies domiciled in emerging markets, and securities issued or guaranteed by foreign governments, their agencies or instrumentalities and supra-national governmental entities, such as the World Bank. Non-U.S. investments may be traded on foreign securities exchanges or in over-the-counter capital markets. Many foreign companies issue both foreign currency and U.S. dollar-denominated securities. The Fund may also invest in American Depositary Receipts ( “ADRs” ) or Global Depositary Receipts ( “GDRs” ), or other securities representing underlying securities of foreign issuers.

10

Non-Principal Investments

Foreign Currency Instruments

The Fund may enter into foreign currency transactions on a spot ( i.e ., cash) basis or on a forward basis ( i.e ., by entering into forward contracts to purchase or sell foreign currencies). A forward currency contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Fund’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions ( i.e ., non deliverable forward currency contracts) may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Fund is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. A contract to sell foreign currency would limit any potential gain which might be realized if the value of the hedged currency increases.

Investment Companies and Pooled Investment Vehicles

The Fund may invest in securities of exchange-traded pooled investment vehicles, open-end or closed-end investment companies, including other exchange-traded funds ( “ETFs” ) and business development companies, that invest primarily in securities of the types in which the Fund may invest directly. The Fund’s ability to invest in other investment companies is limited by the 1940 Act and the related rules and interpretations. The Fund may invest in other investment companies in excess of the limits imposed under the 1940 Act pursuant to exemptive orders obtained by certain investment companies and their sponsors from the SEC, subject to certain conditions and pursuant to a contractual arrangement between the Fund and such investment companies. The Fund may satisfy the Name Policy by investing in investment companies and other pooled investment vehicles that are subject to a comparable name policy and invest in the types of securities in which the Fund may invest directly.

As a shareholder in an investment company or pooled investment vehicle, the Fund bears its ratable share of that investment company’s expenses, and would remain subject to payment of the Fund’s advisory and administrative fees with respect to assets so invested. Shareholders would therefore be subject to duplicative expenses to the extent the Fund invests in other pooled investment vehicles. In addition, the Fund incurs brokerage costs when purchasing and selling shares of ETFs or closed-end funds. Securities of certain investment companies may be leveraged, in which case the value and/or yield of such securities tends to be more volatile than securities of unleveraged investment companies.

Cash Equivalents and Short-Term Investments

Normally, the Fund invests substantially all of its assets to meet its investment objective. The Fund may invest the remainder of its assets in securities with maturities of less than one year or cash equivalents, or it may hold cash. The percentage of the Fund invested in such holdings varies and depends on several factors, including market conditions. For temporary defensive purposes and during periods of high cash inflows or outflows, the Fund may depart from its principal investment strategies and invest part or all of its assets in these securities, or it may hold cash. During such periods, the Fund may not be able to achieve its investment objective. The Fund may adopt a defensive strategy when its portfolio managers believe securities in which the Fund normally invests have elevated risks due to political or economic factors and in other extraordinary circumstances. For more information on eligible short-term investments, see the SAI.

Disclosure of Portfolio Holdings

A description of the policies and procedures with respect to the disclosure of the Fund’s portfolio securities is included in the Fund’s SAI and on the Fund’s website at www.ftportfolios.com.

Additional Risks of Investing in the Fund

Risk is inherent in all investing. Investing in the Fund involves risk, including the risk that you may lose all or part of your investment. There can be no assurance that the Fund will meet its stated objective. Before you invest, you should consider the following supplemental disclosure pertaining to the Principal Risks set forth above as well as additional Non-Principal Risks set forth below in this prospectus.

Principal Risks

CURRENCY RISK. The Fund may hold investments that are denominated in non‑U.S. currencies, or in securities that provide exposure to such currencies, currency exchange rates or interest rates denominated in such currencies. An investment in non-U.S. securities involves risk due to currency exchange rates. Changes in currency exchange rates and the relative value

11

of non-U.S. currencies will affect the value of the Fund’s investments and the value of your Fund shares. Changes in currency exchange rates also may affect the value of interest earned and gains and losses realized on the sale of securities. Currency exchange rates can be very volatile and can change quickly and unpredictably. As a result, the value of an investment in the Fund may change quickly and without warning and you may lose money.

An increase in the strength of the U.S. dollar relative to other currencies may cause the value of the Fund to decline. Certain non-U.S. currencies may be particularly volatile, and non-U.S. governments may intervene in the currency markets, causing a decline in value or liquidity in the Fund’s non-U.S. holdings whose value is tied to the affected non-U.S. currency.

DEPOSITARY RECEIPTS RISK. An investment in depositary receipts involves further risks due to certain features of depositary receipts. Depositary receipts are usually in the form of ADRs or GDRs. ADRs are U.S. dollar-denominated receipts representing securities of foreign-based corporations. ADRs are issued by U.S. banks or trust companies, and entitle the holder to all dividends and capital gains that are paid out on the underlying foreign securities. GDRs are similar to ADRs, but are securities of foreign-based corporations generally issued by international banks in one or more markets around the world. ADRs or GDRs may be less liquid than the underlying securities in their primary trading market. Any distributions paid to the holders of depositary receipts, whether ADRs or GDRs,are usually subject to a fee charged by the depositary.

Holders of depositary receipts may have limited voting rights pursuant to a deposit agreement between the underlying issuer and the depositary. In certain cases, the depositary will vote the securities deposited with it as directed by the underlying issuer’s board of directors. Furthermore, investment restrictions in certain countries may adversely impact the value of depositary receipts because such restrictions may limit the ability to convert securities into depositary receipts and vice versa. Such restrictions may cause shares of the underlying issuer to trade at a discount or premium to the market price of the depositary receipt. Moreover, if depositary receipts are converted into securities, the laws in certain countries may limit the ability of a non-resident to trade the securities and to reconvert the securities to depositary receipts.

Depositary receipts may be “sponsored” or “unsponsored.” Sponsored depositary receipts are established jointly by a depositary and the underlying issuer, whereas unsponsored depositary receipts may be established by a depositary without participation by the underlying issuer. Holders of unsponsored depositary receipts generally bear all the costs associated with establishing the unsponsored depositary receipts. In addition, the issuers of the securities underlying unsponsored depositary receipts are not obligated to disclose material information in the United States and, therefore, there may be less information available regarding such issuers and there may not be a correlation between such information and the market value of the depositary receipts. As a result, the prices of unsponsored ADRs and GDRs may be more volatile than if such instruments were sponsored by the issuer.

Depositary receipts may be unregistered and unlisted. The Fund’s investments may also include depositary receipts that are not purchased in the public markets and are restricted securities that can be offered and sold only to “qualified institutional buyers” under Rule 144A under the Securities Act of 1933, as amended ( “Securities Act” ). Moreover, if adverse market conditions were to develop during the period between the Fund’s decision to sell these types of depositary receipts and the point at which the Fund is permitted or able to sell such security, the Fund might obtain a price less favorable than the price that prevailed when it decided to sell.

EQUITY SECURITIES RISK. Equity securities may decline significantly in price over short or extended periods of time, and such declines may occur in the equity market as a whole, or they may occur in only a particular country, company, industry or sector of the market.

EUROPE RISK. Investments in a single region, even though representing a number of different countries within the region, may be affected by common economic forces and other factors. The Fund is subject to greater risks of adverse events which occur in the European region and may experience greater volatility than a fund that is more broadly diversified geographically. Political or economic disruptions in European countries, even in countries in which the Fund is not invested, may adversely affect security values and thus the Fund’s holdings. A significant number of countries in Europe are member states in the European Union (the “ EU ”), and the member states no longer control their own monetary policies by directing independent interest rates for their currencies. In these member states, the authority to direct monetary policies, including money supply and official interest rates for the Euro, is exercised by the European Central Bank. Furthermore, the European sovereign debt crisis has had, and continues to have, a significant negative impact on the economies of certain European countries and their future economic outlooks.

Continuing uncertainty as to the status of the Euro and the European Monetary Union and the potential for certain countries to withdraw from the institution has created significant volatility in currency and financial markets generally. Any partial or

12

complete dissolution of the EU could have significant adverse effects on currency and financial markets, and on the values of the Fund’s portfolio investments. The United Kingdom’s referendum on June 23, 2016 to leave the European Union (known as “ Brexit ”) sparked depreciation in the value of the British pound, short-term declines in the stock markets and heightened risk of continued economic volatility worldwide. Although the long-term effects of Brexit are difficult to gauge and cannot be fully known, they could have wide ranging implications for the United Kingdom’s economy, including: possible inflation or recession, continued depreciation of the pound, or disruption to Britain’s trading arrangements with the rest of Europe. The United Kingdom is one of the EU’s largest economies; its departure also may negatively impact the EU and Europe as a whole, such as by causing volatility within the union, trigging prolonged economic downturns in certain European countries or sparking additional member states to contemplate departing the EU (thereby perpetuating political instability in the region).

MARKET RISK. The market values of the Fund’s investments may decline, at times sharply and unpredictably. Market values of debt securities are affected by a number of different factors, including changes in interest rates, the credit quality of bond issuers, and general economic and market conditions.

NON-U.S. SECURITIES RISK . The Fund's investment in securities of non-U.S. companies involves other risks not associated with domestic issuers. Investment in non-U.S. securities may involve higher costs than investment in U.S. securities, including higher transaction and custody costs as well as the imposition of additional taxes by non-U.S. governments.

Non-U.S. investments may also involve risks associated with the level of currency exchange rates, less complete financial information about the issuers, less market liquidity, more market volatility and political instability. Future political and economic developments, the possible imposition of withholding taxes on dividend income, the possible seizure or nationalization of non-U.S. holdings, the possible establishment of exchange controls or freezes on the convertibility of currency, or the adoption of other governmental restrictions might adversely affect an investment in non-U.S. securities. Additionally, non-U.S. issuers may be subject to less stringent regulation, and to different accounting, auditing and recordkeeping requirements.

REAL ESTATE INVESTMENT RISK. An investment in REITs and REOCs also involves certain risks, which include, among others, adverse changes in national, state or local real estate conditions (such as the turmoil experienced during the global financial crisis in the residential and commercial real estate markets); obsolescence of properties; changes in the availability, cost and terms of mortgage funds; and the impact of changes in environmental laws. In addition, a REIT that fails to comply with federal tax requirements affecting REITs may be subject to federal income taxation, or the federal tax requirement that a REIT distribute substantially all of its net income to its shareholders may result in a REIT having insufficient capital for future expenditures. The value of a REIT can depend on the structure of and cash flow generated by the company. Like investment companies, REITs have expenses, including advisory and administration fees that are paid by their shareholders. In addition, REITs are subject to certain provisions under federal tax law. The failure of a company to qualify as a REIT could have adverse consequences for the Fund, including significantly reducing return to the Fund on its investment in such company.

Non-Principal Risks

BORROWING AND LEVERAGE RISK. The Fund may borrow for temporary or emergency purposes, including to meet redemption requests, pay dividends or clear portfolio transactions. Such borrowing may, in some instances, effectively leverage the Fund’s portfolio, which could exaggerate changes in the net asset value of the Fund’s shares and affect the Fund’s net income. When the Fund borrows money, it must pay interest and other fees, which will reduce the Fund’s returns if such costs exceed the returns on the portfolio securities purchased or retained with such borrowings. Any such borrowings are intended to be temporary. However, under certain market conditions, including periods of low demand or decreased liquidity, such borrowings might be outstanding for longer periods of time. As prescribed by the 1940 Act, the Fund will be required to maintain specified asset coverage of at least 300% with respect to any bank borrowing immediately following such borrowing. The Fund may be required to dispose of assets on unfavorable terms if market fluctuations or other factors reduce the Fund’s asset coverage to less than the prescribed amount.

CASH TRANSACTIONS RISK . The Fund may, under certain circumstances, effect a portion of creations and redemptions for cash, rather than in-kind securities. As a result, an investment in the Fund may be less tax-efficient than an investment in an ETF that effects its creations and redemptions for in-kind securities. ETFs are able to make in kind redemptions and avoid being taxed on gains on the distributed portfolio securities at the fund level. Because the Fund may effect a portion of redemptions for cash, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. Any recognized gain on these sales by the Fund will generally cause the Fund to recognize a gain it might not otherwise have recognized, or to recognize such gain sooner than would otherwise be required if it were to distribute portfolio securities in-kind. The Fund intends to distribute these gains to shareholders to avoid being taxed on this gain at the fund level and otherwise comply with the special tax rules that apply to it. This strategy may cause shareholders to be subject to tax on gains

13

they would not otherwise be subject to, or at an earlier date than if they had made an investment in a different ETF. Moreover, cash transactions may have to be carried out over several days if the securities market is relatively illiquid, and such transactions may involve considerable brokerage fees and taxes. These brokerage fees and taxes, which will be higher than if the Fund sold and redeemed its shares principally in-kind, will be passed on to purchasers and redeemers of Creation Units in the form of creation and redemption transaction fees. In addition, these factors may result in wider spreads between the bid and the offered prices of the Fund’s shares than for ETFs that distribute portfolio securities in-kind.

COUNTERPARTY RISK. Certain derivative instruments, including forward contracts, that involve counterparties subject the Fund to the risk that the counterparty could default on its obligations under the agreement, either through the counterparty’s bankruptcy or failure to perform its obligations. In the event of default, the Fund could experience lengthy delays in recovering some or all of its assets or no recovery at all.

DEPENDENCE ON KEY PERSONNEL. The Fund is dependent upon the experience and expertise of the Fund’s portfolio managers in providing advisory services with respect to the Fund’s investments. If the Sub-Advisor or a Sub-Sub-Advisor were to lose the services of any of these portfolio managers, its ability to service the Fund could be adversely affected. There can be no assurance that a suitable replacement could be found for any of the portfolio managers in the event of their death, resignation, retirement or inability to act on behalf of the Sub-Advisor or a Sub-Sub-Advisor.

DERIVATIVES AND FOREIGN CURRENCY RISK. The use of foreign currencies and derivative instruments, including forward contracts, involves additional risks and transaction costs which could leave the Fund in a worse position than if it had not used these instruments. Derivatives may entail investment exposures that are greater than their cost would suggest. As a result, a small investment in derivatives can result in losses that greatly exceed the original investment.

Derivatives can be highly volatile, illiquid and difficult to value, and there is the risk that changes in the value of a derivative held by a Fund will not correlate with the asset, index or rate underlying the derivative contract. In addition, when the Fund invests in certain derivative securities, it is effectively leveraging its investments, which could result in exaggerated changes in the net asset value of the Fund’s shares and can result in losses that exceed the amount originally invested. The success of the portfolio managers' derivatives strategies will depend on their ability to assess and predict the impact of market or economic developments on the underlying asset, index or rate and the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions. Liquidity risk exists when a security cannot be purchased or sold at the time desired, or cannot be purchased or sold without adversely affecting the price.

FAILURE TO QUALIFY AS A REGULATED INVESTMENT COMPANY. If, in any year, the Fund fails to qualify as a regulated investment company under the applicable tax laws, the Fund would be taxed as an ordinary corporation. In such circumstances, the Fund could be required to recognize unrealized gains, pay substantial taxes and interest and make substantial distributions before requalifying as a regulated investment company that is accorded special tax treatment. If the Fund fails to qualify as a regulated investment company, distributions to the Fund’s shareholders generally would be eligible for the dividends received deduction in the case of corporate shareholders. See “Federal Tax Matters.”

INFLATION RISK. Inflation risk is the risk that the value of assets or income from investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of a Fund's assets can decline as can the value of a Fund's distributions. Certain securities in which the fund invests may be particularly sensitive to rising interest rates, as the cost of capital rises and borrowing costs increase.

INVESTMENT COMPANIES RISK. The Fund may invest in securities of other investment companies, including ETFs. As a shareholder in other investment companies, the Fund will bear its ratable share of that investment company’s expenses, and would remain subject to payment of the Fund’s advisory and administrative fees with respect to assets so invested. Shareholders would therefore be subject to duplicative expenses to the extent the Fund invests in other investment companies. In addition, the Fund will incur brokerage costs when purchasing and selling shares of ETFs or other exchange-traded investment companies.

ISSUER SPECIFIC CHANGES RISK. The value of an individual security or particular type of security can be more volatile than the market as a whole and can perform differently from the value of the market as a whole.

LEGISLATION/LITIGATION RISK. From time to time, various legislative initiatives are proposed in the United States and abroad, which may have a negative impact on certain companies in which the Fund invests. Such legislation or litigation may cause the Fund to lose value or may result in higher portfolio turnover if the portfolio managers determine to sell such a holding.

14

Fund Organization

The Fund is a series of the Trust, an investment company registered under the 1940 Act. The Fund is treated as a separate fund with its own investment objective and policies. The Trust is organized as a Massachusetts business trust. The Trust's Board is responsible for the overall management and direction of the Trust. The Board elects the Trust’s officers and approves all significant agreements, including those with the investment advisor,Sub-Advisor, Sub-Sub-Advisors, custodian and fund administrative and accounting agent.

Management of the Fund

First Trust, 120 East Liberty Drive, Wheaton, Illinois 60187, is the investment advisor to the Fund. In this capacity, First Trust is responsible for overseeing the Sub-Advisor in the investment of the Fund’s assets, managing the Fund’s business affairs and providing certain clerical, bookkeeping and other administrative services.

First Trust is a limited partnership with one limited partner, Grace Partners of DuPage L.P., and one general partner, The Charger Corporation. Grace Partners of DuPage L.P. is a limited partnership with one general partner, The Charger Corporation, and a number of limited partners. The Charger Corporation is an Illinois corporation controlled by James A. Bowen, the Chief Executive Officer of the Advisor. First Trust discharges its responsibilities subject to the policies of the Board.

First Trust serves as advisor or sub-advisor for seven mutual fund portfolios, 10 exchange-traded funds consisting of 130 series, and 16 closed-end funds. It is also the portfolio supervisor of certain unit investment trusts sponsored by First Trust Portfolios L.P. ( “FTP” ), an affiliate of First Trust, 120 East Liberty Drive, Wheaton, Illinois 60187. FTP specializes in the underwriting, trading and distribution of unit investment trusts and other securities. FTP is the principal underwriter of the shares of the Fund.

The Fund and First Trust have retained HRES LLC, a Delaware limited liability company, to serve as investment sub-advisor. In this capacity, HRES LLC is responsible for the selection and ongoing monitoring of the securities in the Fund’s investment portfolio and overseeing the Sub-Sub-Advisors in the investment of the Fund’s assets. HRES LLC, located at 191 N. Wacker Drive, 25th Floor, Chicago, Illinois 60606, is a leading global real estate investment management firm with total assets under management of approximately U.S. $4.9 billion as of January 31, 2018.

Heitman HK Limited, a company whose liability is limited by shares domiciled in Hong Kong and an affiliate of HRES LLC, has been retained by the Fund, the Advisor and Sub-Advisor to select and monitor Real Estate Securities located in the Asia-Pacific region for the Fund’s investment portfolio. Heitman HK Limited is a registered investment advisor with the SEC. Heitman HK Limited is located at 15F LHT Tower, 31 Queens Road, Central Hong Kong with total assets under management of approximately U.S. $1.3 billion as of January 31, 2018.

Heitman GmbH, a company with limited liability domiciled in Germany and an affiliate of HRES LLC, has been retained by the Fund, the Advisor and Sub-Advisor to provide recommendations regarding the selection and ongoing monitoring of Real Estate Securities located in Europe for the Fund’s investment portfolio. Heitman GmbH is a registered investment advisor with the SEC. Heitman GmbH is located at Maximilianstrasse 35A, Munich, Germany 80539, with total assets under management of approximately $959 million as of January 31, 2018.

“HRES LLC,”“Heitman HK Limited” and “Heitman GmbH” are collectively referred to in this prospectus as “Heitman.”

The individuals listed below, share responsibilities for the day-to-day management of the group and the Fund’s investment portfolio.

•

Jerry Ehlinger, CFA, is Managing Director of HRES LLC and the Lead Portfolio Manager in Heitman’s North American Public Real Estate Securities group. He also serves as a Portfolio Manager for the firm’s global real estate securities strategies. Throughout his career, Jerry has held a number of related investment positions in the REIT industry. Before joining Heitman in 2013, Jerry was Lead Portfolio Manager and Head of Real Estate Securities, Americas at DB/RREEF Real Estate. Prior, Jerry served as Senior Vice President and Portfolio Manager of Heitman’s real estate securities group from 2000 to 2004. He began his career at Morgan Stanley in 1996 where he primarily covered the REIT sector both as a sell-side analyst and as a senior research associate at Morgan Stanley Asset Management. Jerry received an MS in Finance, Investment and Banking from the University of Wisconsin-Madison and a BS in Finance from the University of Wisconsin-Whitewater. Among

15

other professional affiliations, Jerry is a member of the National Multi Housing Council, International Council of Shopping Centers, the CFA Institute, the CFA Society of Chicago, and the National Association of Real Estate Investment Trusts.

•	John White is Managing Director of Heitman HK Limited and the Lead Portfolio Manager in Heitman’s Asia-Pacific Public Real Estate Securities group. He is an equity owner of the firm and a member of Heitman’s Management Committee. He also serves as a Portfolio Manager for the firm's global real estate securities strategies. John has over 20 years of experience in the public and private equity and debt real estate markets across the Asia-Pacific region. Prior to joining Heitman in 2010, John was co-head of real estate securities at Challenger (Heitman’s Asian JV partner for real estate securities) for five years; he was also senior investment manager, real estate securities at HSBC Asset Management from 2001. Before moving to investment management, John worked in investment banking as a senior property analyst at HSBC and as a manager — real estate credit at ANZ Banking Group in Australia and in South-East Asia. He began his career as a real estate valuer at Landauer and Chesterton. John received a BBus in Land Economy from University of Western Sydney-Hawkesbury and a Graduate Diploma in Applied Finance and Investment from the Securities Institute of Australia. He is a member of the Royal Institute of Chartered Surveyors, the Asian Public Real Estate Association, the Australian Property Institute and the Financial Services Institute of Australasia.
•	Jacques Perdrix is a Senior Vice President in Heitman’s European Public Real Estate Securities group. His role with Heitman focuses on portfolio management, including fundamental company and market analysis. Prior to joining Heitman, Mr. Perdrix was at Griffin Capital Management where he worked as an analyst and assistant portfolio manager on long-only and long/short equity and fixed income funds covering mid/large-caps on a broad range of sectors and geographies. Previously, Mr. Perdrix worked at equity long/short hedge fund Gugner Partners as a senior analyst and back-up trader focusing on European small/mid-caps across all sectors. Mr. Perdrix started his career within Citigroup’s Investment Banking Division, M&A Financial Institutions Group, in both Paris and London. Mr. Perdrix, a French national, received a Specialised Master’s in Corporate Finance from EM Lyon School of Management and a Master of Science in Management from ESC Grenoble School of Management. He is FSA qualified.
•	Andreas Welter is a Senior Vice President in Heitman’s European Public Real Estate Securities group. His role with Heitman focuses on portfolio construction, fundamental company and market analysis supporting the Portfolio Management team. Prior to joining the firm, Mr. Welter was at Deutsche Bank AG, where he was a senior sell-side equity research analyst for three years. In that time, Mr. Welter covered companies in various industry sectors in Germany ( e.g. , real estate, financials, construction, logistics). Previously, Mr. Welter worked at the Middle Office & Advisory Desk of B. Metzler seel. Sohn & Co., one of Germany’s largest family-owned investment managers. Mr. Welter earned the title of Bankkaufmann (apprenticeship in banking) from the Chamber of Commerce and Industry Frankfurt and holds a Diploma in International Business Administration (Diplom-Betriebswirt) from one of the top-ranked universities in Europe (Hochschule Darmstadt).

For additional information concerning First Trust, the Sub-Advisor and Sub-Sub-Advisors, including a description of the services provided to the Fund, see the Fund’s SAI. Additional information about the portfolio managers’ compensation, other accounts managed by the portfolio managers and the portfolio managers’ ownership of securities in the Fund is provided in the SAI.

Management Fee

Pursuant to the Investment Management Agreement, First Trust supervises HRES LLC and its management of the investment of the Fund’s assets and pays HRES LLC for its services as the Fund’s sub-advisor. First Trust is responsible for the Fund’s expenses, including the cost of transfer agency, sub-advisory, custody, fund administration, legal, audit and other services, but excluding fee payments under the Investment Management Agreement, interest, taxes, acquired fund fees and expenses, if any, brokerage commissions and other expenses connected with the execution of portfolio transactions, distribution and service fees pursuant to a Rule 12b-1 plan, if any, and extraordinary expenses.

The Fund has agreed to pay First Trust an annual management fee equal to 0.95% of its average daily net assets.

A discussion regarding the Board’s approval of the continuation of the Investment Management Agreement, Investment Sub-Advisory Agreement and Investment Sub-Sub-Advisory Agreements for the Fund is available in the Fund’s Annual Report to Shareholders for the year ended October 31, 2017.

16

How to Buy and Sell Shares

Most investors will buy and sell shares of the Fund in secondary market transactions through brokers. Shares of the Fund are expected to be listed for trading on the secondary market on NYSE Arca. Shares can be bought and sold throughout the trading day like other publicly traded shares. There is no minimum investment when buying shares on NYSE Arca. Although shares are generally purchased and sold in “round lots” of 100 shares, brokerage firms typically permit investors to purchase or sell shares in smaller “odd lots,” at no per-share price differential. When buying or selling shares through a broker, investors should expect to incur customary brokerage commissions, investors may receive less than the net asset value of the shares because shares are bought and sold at market prices rather than net asset value, and investors may pay some or all of the spread between the bid and the offer price in the secondary market on each leg of a round trip (purchase and sale) transaction. Share prices are reported in dollars and cents per share.

For purposes of the 1940 Act, the Fund is treated as a registered investment company, and, absent an available exemption or exemptive relief, the acquisition of shares by other registered investment companies and companies relying on Sections 3(c)(1) or 3(c)(7) of the 1940 Act is subject to the restrictions of Section 12(d)(1) of the 1940 Act.

Book Entry

Shares are held in book-entry form, which means that no share certificates are issued. The Depository Trust Company ( “DTC” ) or its nominee is the record owner of all outstanding shares of the Fund and is recognized as the owner of all shares for all purposes.

Investors owning shares are beneficial owners as shown on the records of DTC or its participants. DTC serves as the securities depository for all shares. Participants in DTC include securities brokers and dealers, banks, trust companies, clearing corporations and other institutions that directly or indirectly maintain a custodial relationship with DTC. As a beneficial owner of shares, you are not entitled to receive physical delivery of share certificates or to have shares registered in your name, and you are not considered a registered owner of shares. Therefore, to exercise any right as an owner of shares, you must rely upon the procedures of DTC and its participants. These procedures are the same as those that apply to any other stocks that you hold in book-entry or “street name” form.

Share Trading Prices

The trading prices of shares of the Fund on NYSE Arca may differ from the Fund’s daily net asset value and can be affected by market forces of supply and demand, economic conditions and other factors.

Information regarding the intra-day value of the shares of the Fund, also referred to as the “indicative optimized portfolio value” ( “IOPV” ), is disseminated every 15 seconds throughout the Fund’s trading day by the national securities exchange on which the shares are listed or by market data vendors or other information providers. The IOPV should not be viewed as a “real-time” update of the net asset value per share of the Fund because the IOPV may not be calculated in the same manner as the net asset value, which is computed once a day, generally at the end of the business day. The price of a non-U.S. security that is primarily traded on a non-U.S. exchange will be updated, using the last sale price, every 15 seconds throughout the trading day, provided that, upon the closing of such non-U.S. exchange, the closing price of the security, after being converted to U.S. dollars, will be used. This will likely cause the IOPV to deviate significantly from the true market value of the portfolio. Furthermore, in calculating the IOPV of the Fund’s shares, exchange rates may be used throughout the day (9:00 a.m. to 4:15 p.m., Eastern time) that may differ from those used to calculate the net asset value per share of the Fund and consequently may result in differences between the net asset value and the IOPV. The Fund is not involved in, or responsible for, the calculation or dissemination of the IOPV of shares of the Fund and the Fund does not make any warranty as to its accuracy.

Frequent Purchases and Redemptions of the Fund’s Shares

The Fund imposes no restrictions on the frequency of purchases and redemptions ( “market timing” ). In determining not to approve a written, established policy, the Board evaluated the risks of market timing activities by the Fund’s shareholders. The Board considered that the Fund’s shares can only be purchased and redeemed directly from the Fund in Creation Units by broker-dealers and large institutional investors that have entered into participation agreements ( i.e. , authorized participants ( “APs” )) and that the vast majority of trading in the Fund’s shares occurs on the secondary market. Because the secondary market trades do not involve the Fund directly, it is unlikely those trades would cause many of the harmful effects of market timing, including dilution, disruption of portfolio management, increases in the Fund’s trading costs and the realization of capital gains. As the Fund may effect the purchase or redemption of Creation Units in exchange wholly or partially for cash, the Board noted that such trades could result in dilution to the Fund and increased transaction costs, which could negatively

17

impact the Fund’s ability to achieve its investment objective. However, the Board noted that direct trading by APs is critical to ensuring that the shares trade at or close to net asset value. In addition, the Fund imposes fixed and variable transaction fees on purchases and redemptions of Creation Units to cover the custodial and other costs incurred by the Fund in effecting trades. Finally, the Advisor monitors purchase and redemption orders from APs for patterns of abusive trading. The Fund reserves the right to reject purchase and redemption orders from APs for patterns of abusive trading and the Fund reserves the right to not accept orders from APs that the Advisor has determined may be disruptive to the management of the Fund, or otherwise not in the Fund’s best interests.

Dividends, Distributions and Taxes

Dividends from net investment income, if any, are declared and paid quarterly by the Fund. The Fund distributes its net realized capital gains, if any, to shareholders at least annually.

Distributions in cash may be reinvested automatically in additional whole shares only if the broker through whom you purchased shares makes such option available. Such shares will generally be reinvested by the broker based upon the market price of those shares and investors may be subject to customary brokerage commissions charged by the broker.

Federal Tax Matters

This section summarizes some of the main U.S. federal income tax consequences of owning shares of the Fund. This section is current as of the date of this prospectus. Tax laws and interpretations change frequently, and these summaries do not describe all of the tax consequences to all taxpayers. For example, these summaries generally do not describe your situation if you are a corporation, a non-U.S. person, a broker-dealer, or other investor with special circumstances. In addition, this section does not describe your state, local or non-U.S. tax consequences.

This federal income tax summary is based in part on the advice of counsel to the Fund. The Internal Revenue Service could disagree with any conclusions set forth in this section. In addition, counsel to the Fund was not asked to review, and has not reached a conclusion with respect to, the federal income tax treatment of the assets to be included in the Fund. This may not be sufficient for you to use for the purpose of avoiding penalties under federal tax law.

As with any investment, you should seek advice based on your individual circumstances from your own tax advisor.

Fund Status

The Fund intends to continue to qualify or qualify as a “regulated investment company” under the federal tax laws. If the Fund qualifies as a regulated investment company and distributes its income as required by the tax law, the Fund generally will not pay federal income taxes.

Distributions

The Fund’s distributions are generally taxable. After the end of each year, you will receive a tax statement that separates the distributions of the Fund into two categories, ordinary income distributions and capital gain dividends. Ordinary income distributions are generally taxed at your ordinary tax rate; however, as further discussed below, certain ordinary income distributions received from the Fund may be taxed at the capital gains tax rates. Generally, you will treat all capital gain dividends as long-term capital gains regardless of how long you have owned your shares. To determine your actual tax liability for your capital gain dividends, you must calculate your total net capital gain or loss for the tax year after considering all of your other taxable transactions, as described below. In addition, the Fund may make distributions that represent a return of capital for tax purposes and thus will generally not be taxable to you; however, such distributions may reduce your tax basis in your shares, which could result in you having to pay higher taxes in the future when shares are sold, even if you sell the shares at a loss from your original investment. The tax status of your distributions from the Fund is not affected by whether you reinvest your distributions in additional shares or receive them in cash. The income from the Fund that you must take into account for federal income tax purposes is not reduced by amounts used to pay a deferred sales fee, if any. The tax laws may require you to treat distributions made to you in January as if you had received them on December 31 of the previous year.

Income from the Fund may also be subject to a 3.8% “Medicare tax.” This tax generally applies to your net investment income if your adjusted gross income exceeds certain threshold amounts, which are $250,000 in the case of married couples filing joint returns and $200,000 in the case of single individuals.

18

Dividends Received Deduction

A corporation that owns shares generally will not be entitled to the dividends received deduction with respect to many dividends received from the Fund because the dividends received deduction is generally not available for distributions from regulated investment companies. However, certain ordinary income dividends on shares that are attributable to qualifying dividends received by the Fund from certain corporations may be reported by the Fund as being eligible for the dividends received deduction.

Capital Gains and Losses and Certain Ordinary Income Dividends

If you are an individual, the maximum marginal stated federal tax rate for net capital gain is generally 20% (15% or 0% for taxpayers with taxable incomes below certain thresholds). Some portion of your capital gain dividends may be taxed at a higher maximum stated tax rate. Capital gain received from assets held for more than one year that is considered “unrecaptured section 1250 gain” (which may be the case, for example, with some capital gains attributable to equity interests in real estate investment trusts that constitute interests in entities treated as real estate investment trusts for federal income tax purposes) is taxed at a maximum marginal stated federal tax rate of 25%. In the case of capital gain dividends, the determination of which portion of the capital gain dividend, if any, is subject to the 25% tax rate, will be made based on rules prescribed by the United States Treasury. Capital gains may also be subject to the Medicare tax described above.

Net capital gain equals net long-term capital gain minus net short-term capital loss for the taxable year. Capital gain or loss is long-term if the holding period for the asset is more than one year and is short-term if the holding period for the asset is one year or less. You must exclude the date you purchase your shares to determine your holding period. However, if you receive a capital gain dividend from the Fund and sell your share at a loss after holding it for six months or less, the loss will be recharacterized as long-term capital loss to the extent of the capital gain dividend received. The tax rates for capital gains realized from assets held for one year or less are generally the same as for ordinary income. The Internal Revenue Code of 1986, as amended, treats certain capital gains as ordinary income in special situations.

Ordinary income dividends received by an individual shareholder from a regulated investment company such as the Fund are generally taxed at the same rates that apply to net capital gain (as discussed above), provided certain holding period requirements are satisfied and provided the dividends are attributable to qualifying dividends received by the Fund itself. Distributions with respect to shares in real estate investment trusts are qualifying dividends only in limited circumstances. The Fund will provide notice to its shareholders of the amount of any distribution which may be taken into account as a dividend which is eligible for the capital gains tax rates.

Sale of Shares

If you sell or redeem your shares, you will generally recognize a taxable gain or loss. To determine the amount of this gain or loss, you must subtract your tax basis in your shares from the amount you receive in the transaction. Your tax basis in your shares is generally equal to the cost of your shares, generally including sales charges. In some cases, however, you may have to adjust your tax basis after you purchase your shares.

Taxes on Purchase and Redemption of Creation Units

If you exchange securities for Creation Units you will generally recognize a gain or a loss. The gain or loss will be equal to the difference between the market value of the Creation Units at the time and your aggregate basis in the securities surrendered and the cash component paid. If you exchange Creation Units for securities, you will generally recognize a gain or loss equal to the difference between your basis in the Creation Units and the aggregate market value of the securities received and the cash redemption amount. The Internal Revenue Service, however, may assert that a loss realized upon an exchange of securities for Creation Units or Creation Units for securities cannot be deducted currently under the rules governing “wash sales,” or on the basis that there has been no significant change in economic position.

Treatment of Fund Expenses

Expenses incurred and deducted by the Fund will generally not be treated as income taxable to you. In some cases, however, you may be required to treat your portion of these Fund expenses as income. You may not be able to deduct some or all of these expenses.

19

Non-U.S. Tax Credit

Because the Fund invests in non-U.S. securities, the tax statement that you receive may include an item showing non-U.S. taxes the Fund paid to other countries. In this case, dividends taxed to you will include your share of the taxes the Fund paid to other countries. You may be able to deduct or receive a tax credit for your share of these taxes.

Non-U.S. Investors

If you are a non-U.S. investor ( i.e. , an investor other than a U.S. citizen or resident or a U.S. corporation, partnership, estate or trust), you should be aware that, generally, subject to applicable tax treaties, distributions from the Fund will be characterized as dividends for federal income tax purposes (other than dividends which the Fund properly reports as capital gain dividends) and will be subject to U.S. federal income taxes, including withholding taxes, subject to certain exceptions described below. However, distributions received by a non-U.S. investor from the Fund that are properly reported by the Fund as capital gain dividends may not be subject to U.S. federal income taxes, including withholding taxes, provided that the Fund makes certain elections and certain other conditions are met. Distributions from the Fund that are properly reported by the Fund as an interest-related dividend attributable to certain interest income received by the Fund or as a short-term capital gain dividend attributable to certain net short-term capital gain income received by the Fund may not be subject to U.S. federal income taxes, including withholding taxes when received by certain non-U.S. investors, provided that the Fund makes certain elections and certain other conditions are met.

Distributions may be subject to a U.S. withholding tax of 30% in the case of distributions to (i) certain non-U.S. financial institutions that have not entered into an agreement with the U.S. Treasury to collect and disclose certain information and are not resident in a jurisdiction that has entered into such an agreement with the U.S. Treasury and (ii) certain other non-U.S. entities that do not provide certain certifications and information about the entity’s U.S. owners. Dispositions of shares by such persons may be subject to such withholding after December 31, 2018.

Investments in Certain Non-U.S. Corporations

If the Fund holds an equity interest in any passive foreign investment companies, which are generally certain non-U.S. corporations that receive at least 75% of their annual gross income from passive sources (such as interest, dividends, certain rents and royalties or capital gains) or that hold at least 50% of their assets in investments producing such passive income, the Fund could be subject to U.S. federal income tax and additional interest charges on gains and certain distributions with respect to those equity interests, even if all the income or gain is timely distributed to its shareholders. The Fund will not be able to pass through to its shareholders any credit or deduction for such taxes. The Fund may be able to make an election that could ameliorate these adverse tax consequences. In this case, the Fund would recognize as ordinary income any increase in the value of such passive foreign investment companies shares, and as ordinary loss any decrease in such value to the extent it did not exceed prior increases included in income. Under this election, the Fund might be required to recognize in a year income in excess of its distributions from passive foreign investment companies and its proceeds from dispositions of passive foreign investment companies stock during that year, and such income would nevertheless be subject to the distribution requirement and would be taken into account for purposes of the 4% excise tax. Dividends paid by passive foreign investment companies are not treated as qualified dividend income.

Distribution Plan

FTP serves as the distributor of Creation Units for the Fund on an agency basis. FTP does not maintain a secondary market in shares.

The Board has adopted a Distribution and Service Plan pursuant to Rule 12b-1 under the 1940 Act. In accordance with the Rule 12b-1 plan, the Fund is authorized to pay an amount up to 0.25% of its average daily net assets each year to reimburse FTP for amounts expended to finance activities primarily intended to result in the sale of Creation Units or the provision of investor services. FTP may also use this amount to compensate securities dealers or other persons that are APs for providing distribution assistance, including broker-dealer and shareholder support and educational and promotional services.

The Fund does not currently pay 12b-1 fees, and pursuant to a contractual arrangement, the Fund will not pay 12b-1 fees any time before March 31, 2019. However, in the event 12b-1 fees are charged in the future, because these fees are paid out of the Fund's assets, over time these fees will increase the cost of your investment and may cost you more than certain other types of sales charges.

20

Net Asset Value

The Fund’s net asset value is determined as of the close of trading (normally 4:00 p.m., Eastern time) on each day the New York Stock Exchange is open for business. Net asset value is calculated for the Fund by taking the market price of the Fund’s total assets, including interest or dividends accrued but not yet collected, less all liabilities, and dividing such amount by the total number of shares outstanding. The result, rounded to the nearest cent, is the net asset value per share. All valuations are subject to review by the Fund’s Board or its delegate.

The Fund’s investments will be valued at market value or, in the absence of market value with respect to any investment, at fair value in accordance with valuation procedures adopted by the Trust’s Board and in accordance with the 1940 Act. Portfolio securities listed on any exchange other than The Nasdaq Stock Market LLC ( “Nasdaq” ) and the London Stock Exchange Alternative Investment Market ( “AIM” ) will be valued at the last sale price on the exchange on which they are principally traded. Securities listed on the Nasdaq or the AIM will be valued at the official closing price. Securities traded on more than one securities exchange will be valued at the last sale price or official closing price, as applicable, at the close of the exchange representing the principal market for such securities. Portfolio securities traded in the over-the-counter market are valued at their closing bid prices. Short-term investments that mature in less than 60 days when purchased will be valued at cost adjusted for amortization of premiums and accretion of discount.

Certain securities may not be able to be priced by pre-established pricing methods. Such securities may be valued by the Board or its delegate at fair value. The use of fair value pricing by the Fund is governed by valuation procedures adopted by the Board and in accordance with the provisions of the 1940 Act. These securities generally include, but are not limited to, certain restricted securities (securities which may not be publicly sold without registration under the Securities Act) for which a pricing service is unable to provide a market price; securities whose trading has been formally suspended; a security whose market price is not available from a pre-established pricing source; a security with respect to which an event has occurred that is likely to materially affect the value of the security after the market has closed but before the calculation of the Fund’s net asset value or make it difficult or impossible to obtain a reliable market quotation; and a security whose price, as provided by the pricing service, does not reflect the security’s “fair value.” As a general principle, the current “fair value” of a security would appear to be the amount which the owner might reasonably expect to receive for the security upon its current sale. The use of fair value prices by the Fund generally results in the prices used by the Fund that may differ from current market quotations or official closing prices on the applicable exchange. A variety of factors may be considered in determining the fair value of such securities. Valuing the Fund’s securities using fair value pricing will result in using prices for those securities that may differ from current market valuations. See the Fund’s SAI for details.

Valuing the Fund’s holdings using fair value pricing will result in using prices for those holdings that may differ from current market valuations.

Because foreign securities exchanges may be open on different days than the days during which an investor may purchase or sell shares of the Fund, the value of the Fund’s securities may change on days when investors are not able to purchase or sell shares of the Fund. The value of securities denominated in foreign currencies is converted into U.S. dollars at the exchange rates in effect at the time of valuation.

Fund Service Providers

Brown Brothers Harriman & Co., 50 Post Office Square, Boston, Massachusetts 02110, acts as the administrator, accounting agent, custodian and transfer agent for the Fund. Chapman and Cutler LLP, 111 West Monroe Street, Chicago, Illinois 60603, serves as legal counsel to the Fund. First Trust serves as the fund reporting agent for the Fund.

Premium/Discount Information

The table that follows presents information about the differences between the Fund’s daily market price on NYSE Arca, Inc. and its net asset value. The “Market Price” of the Fund generally is determined using the midpoint between the highest bid and lowest offer on NYSE Arca, Inc., as of the time the Fund’s net asset value is calculated. The Fund’s Market Price may be at, above, or below its net asset value. The net asset value of the Fund will fluctuate with changes in the market value of its portfolio holdings. The Market Price of the Fund will fluctuate in accordance with changes in its net asset value, as well as market supply and demand.

21

Premiums or discounts are the differences (generally expressed as a percentage) between the net asset value and Market Price of the Fund on a given day, generally at the time net asset value is calculated. A premium is the amount that the Fund is trading above the reported net asset value. A discount is the amount that the Fund is trading below the reported net asset value.

The following information shows the frequency distribution of premiums and discounts of the daily bid/ask price of the Fund against the Fund’s net asset value. The information shown for the Fund is for the period indicated. Shareholders may pay more than net asset value when they buy Fund shares and receive less than net asset value when they sell those shares because shares are bought and sold at current market price. All data presented here represents past performance, which cannot be used to predict future results. Information about the premiums and discounts at which the Fund’s shares have traded is available on the Fund’s website at www.ftportfolios.com.

First Trust Heitman Global Prime Real Estate ETF (PRME)
Bid/Ask Midpoint vs. Net Asset Value

Number of Days Bid/Ask Midpoint At/Above Net Asset Value

	0.00% – 0.49%	0.50% – 0.99%	1.00% – 1.99%	>=2.00%
12 Months Ended 12/31/2017	14	10	1	0

Number of Days Bid/Ask Midpoint Below Net Asset Value

	0.00% – 0.49%	0.50% – 0.99%	1.00% – 1.99%	>=2.00%
12 Months Ended 12/31/2017	58	119	40	9

Total Return Information

The table below compares the total return of the Fund to a broad-based security market index. The information presented for the Fund is for the period indicated.

“Average annual total returns” represent the average annual change in the value of an investment over the period indicated. “Cumulative total returns” represent the total change in value of an investment over the period indicated. The net asset value per share of the Fund is the value of one share of the Fund and is computed by dividing the value of all assets of the Fund (including accrued interest and dividends), less liabilities (including accrued expenses and dividends declared but unpaid), by the total number of outstanding shares. The net asset value return is based on the net asset value per share of the Fund, and the market return is based on the market price per share of the Fund. The price used to calculate market return ( “Market Price” ) generally is determined by using the midpoint between the highest bid and the lowest offer on NYSE Arca, as of the time that the Fund's net asset value is calculated. Since the shares of the Fund typically do not trade in the secondary market until several days after the Fund's inception, for the period from inception to the first day of secondary market trading in shares of the Fund, the net asset value of the Fund is used as a proxy for the secondary market trading price to calculate market returns. Market and net asset value returns assume that all distributions have been reinvested in the Fund at Market Price and net asset value, respectively. An index is a statistical composite that tracks a specified financial market or sector. Unlike the Fund, an index does not actually hold a portfolio of securities and therefore does not incur the expenses incurred by the Fund. These expenses negatively impact the performance of the Fund. Also, market returns do not include brokerage commissions that may be payable on secondary market transactions. If brokerage commissions were included, market returns would be lower. The total returns reflect the reinvestment of dividends on securities in the Indices. The returns shown in the table below do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or the redemption or sale of shares of the Fund. The investment return and principal value of shares of the Fund will vary with changes in market conditions. Shares of the Fund may be worth more or less than their original cost when they are redeemed or sold in the market. The Fund's past performance is no guarantee of future results.

22

23

Financial Highlights

The financial highlights table is intended to help you understand the Fund's financial performance for the periods shown. Certain information reflects financial results for a single share of the Fund. The total returns represent the rate that an investor would have earned (or lost) on an investment in the Fund (assuming reinvestment of all dividends and distributions). The information for the periods indicated has been derived from financial statements audited by Deloitte & Touche LLP, whose report, along with the Fund's financial statements, is included in the Fund's Annual Report to Shareholders dated October 31, 2017 and is incorporated by reference in the Fund's SAI, which is available upon request.

(a)

Inception date is November 11, 2015, which is consistent with the commencement of investment operations and is the date the initial creation units were established.

(b)

Total return is calculated assuming an initial investment made at the net asset value at the beginning of the period, reinvestment of all distributions at net asset value during the period, and redemption at net asset value on the last day of the period. The returns presented do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or the redemption or sale of Fund shares. Total return is calculated for the time period presented and is not annualized for periods of less than a year.

(c)	Annualized.
(d)	Portfolio turnover is calculated for the time period presented and is not annualized for periods of less than a year and does not include securities received or delivered from processing creations or redemptions and in-kind transactions.

24

Other Information

Continuous Offering

The Fund issues, on a continuous offering basis, its shares in one or more groups of a fixed number of Fund shares (each such group of such specified number of individual Fund shares, a “Creation Unit Aggregation” ). The method by which Creation Unit Aggregations of Fund shares are created and traded may raise certain issues under applicable securities laws. Because new Creation Unit Aggregations of shares are issued and sold by the Fund on an ongoing basis, a “distribution,” as such term is used in the Securities Act, may occur at any point. Broker-dealers and other persons are cautioned that some activities on their part may, depending on the circumstances, result in their being deemed participants in a distribution in a manner which could render them statutory underwriters and subject them to the prospectus delivery requirement and liability provisions of the Securities Act.

For example, a broker-dealer firm or its client may be deemed a statutory underwriter if it takes Creation Unit Aggregations after placing an order with FTP, breaks them down into constituent shares and sells such shares directly to customers, or if it chooses to couple the creation of a supply of new shares with an active selling effort involving solicitation of secondary market demand for shares. A determination of whether one is an underwriter for purposes of the Securities Act must take into account all the facts and circumstances pertaining to the activities of the broker-dealer or its client in the particular case, and the examples mentioned above should not be considered a complete description of all the activities that could lead to a characterization as an underwriter.

Broker-dealer firms should also note that dealers who are not “underwriters” but are effecting transactions in shares, whether or not participating in the distribution of shares, are generally required to deliver a prospectus. This is because the prospectus delivery exemption in Section 4(a)(3) of the Securities Act is not available in respect of such transactions as a result of Section 24(d) of the 1940 Act. As a result, broker-dealer firms should note that dealers who are not underwriters but are participating in a distribution (as contrasted with ordinary secondary market transactions) and thus dealing with the shares that are part of an overallotment within the meaning of Section 4(a)(3)(C) of the Securities Act would be unable to take advantage of the prospectus delivery exemption provided by Section 4(a)(3) of the Securities Act. Firms that incur a prospectus delivery obligation with respect to shares are reminded that, under Rule 153 of the Securities Act, a prospectus delivery obligation under Section 5(b)(2) of the Securities Act owed to a broker-dealer in connection with a sale on NYSE Arca is satisfied by the fact that the prospectus is available from NYSE Arca upon request. The prospectus delivery mechanism provided in Rule 153 is available with respect to transactions on a national securities exchange, a trading facility or an alternative trading system.

25

      

[THIS PAGE INTENTIONALLY LEFT BLANK.]

[THIS PAGE INTENTIONALLY LEFT BLANK.]

First Trust Heitman Global Prime Real Estate ETF

For More Information

For more detailed information on the Fund, several additional sources of information are available to you. The SAI, incorporated by reference into this prospectus, contains detailed information on the Fund's policies and operation. Additional information about the Fund's investments is available in the annual and semi-annual reports to shareholders. In the Fund's annual report, you will find a discussion of the market conditions and investment strategies that significantly impacted the Fund's performance during the last fiscal year. The Fund's most recent SAI, annual and semi-annual reports and certain other information are available free of charge by calling the Fund at (800) 621-1675, on the Fund's website at www.ftportfolios.com or through your financial advisor. Shareholders may call the toll-free number above with any inquiries.

You may obtain this and other information regarding the Fund, including the SAI and the Codes of Ethics adopted by First Trust, FTP and the Trust, directly from the Securities and Exchange Commission (the “SEC” ). Information on the SEC’s website is free of charge. Visit the SEC’s online EDGAR database at www.sec.gov or in person at the SEC’s Public Reference Room in Washington, D.C., or call the SEC at (202) 551-8090 for information on the Public Reference Room. You may also request information regarding the Fund by sending a request (along with a duplication fee) to the SEC’s Public Reference Section, 100 F Street, N.E., Washington, D.C. 20549-1520 or by sending an electronic request to publicinfo@sec.gov.

First Trust Advisors L.P.
120 East Liberty Drive, Suite 400
Wheaton, Illinois 60187
(800) 621-1675
www.ftportfolios.com

SEC File #: 333-174332

811-22559

Prospectus

First Trust Low Duration Opportunities ETF

Ticker Symbol:	LMBS
Exchange:	Nasdaq

First Trust Low Duration Opportunities ETF (the “Fund” ) lists and principally trades its shares on The Nasdaq Stock Market LLC ( “Nasdaq” or the “Exchange” ). Market prices may differ to some degree from the net asset value of the shares. Unlike mutual funds, the Fund issues and redeems shares at net asset value, only in large specified blocks each consisting of 50,000 shares (each such block of shares called a “Creation Unit,” and collectively, the “Creation Units” ). The Fund’s Creation Units are generally issued and redeemed for cash and, in certain circumstances, in-kind for securities in which the Fund invests, and only to and from broker-dealers and large institutional investors that have entered into participation agreements.

The Fund is a series of First Trust Exchange-Traded Fund IV (the “Trust” ) and an actively managed exchange-traded fund organized as a separate series of a registered management investment company.

Except when aggregated in Creation Units, the shares are not redeemable securities of the Fund.

The Securities and Exchange Commission has not approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

Table of Contents

Summary Information	3
Additional Information on the Fund's Investment Objectives and Strategies	10
Fund Investments	10
Additional Risks of Investing in the Fund	12
Fund Organization	16
Management of the Fund	16
How to Buy and Sell Shares	17
Dividends, Distributions and Taxes	18
Federal Tax Matters	18
Distribution Plan	20
Net Asset Value	20
Fund Service Providers	21
Premium/Discount Information	21
Total Return Information	22
Financial Highlights	23
Other Information	24

Investment Objectives

The First Trust Low Duration Opportunities ETF's (the " Fund ") primary investment objective is to generate current income. The Fund's secondary investment objective is to provide capital appreciation.

Fees and Expenses of the Fund

The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund. Investors purchasing and selling shares may be subject to costs (including customary brokerage commissions) charged by their broker, which are not reflected in the table below.

Shareholder Fees
(fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

None

    

(1)	Although the Fund has adopted a 12b-1 plan that permits it to pay up to 0.25% per annum, it will not pay 12b-1 fees at any time before March 31, 2019.

Example

The example below is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. This example does not take into account customary brokerage commissions that you pay when purchasing or selling shares of the Fund in the secondary market.

The example assumes that you invest $10,000 in the Fund for the time periods indicated. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain at current levels until March 31, 2019, and thereafter at 0.93% to represent the imposition of the 12b-1 fee of 0.25% per annum of the Fund’s average daily net assets. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

1 Year	3 Years	5 Years	10 Years
$69	$271	$490	$1,120

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 190% of the average value of its portfolio.

Principal Investment Strategies

Under normal market conditions, the Fund will seek to achieve its investment objectives by investing at least 80% of its net assets (including investment borrowings) in mortgage-related debt securities and other mortgage-related instruments (collectively, “Mortgage-Related Investments” ). The Fund normally expects to invest in Mortgage-Related Investments tied to residential and commercial mortgages. Mortgage-Related Investments consist of: (1) residential mortgage-backed securities ( RMBS ); (2) commercial mortgage-backed securities ( CMBS ); (3) stripped mortgage-backed securities ( SMBS ), which are mortgage-backed securities where mortgage payments are divided up between paying the loan’s principal and paying the loan’s interest; and (4) collateralized mortgage obligations ( CMOs ) and real estate mortgage investment conduits ( REMICs ) where they are divided into multiple classes with each class being entitled to a different share of the principal and/or interest

3

payments received from the pool of underlying assets. Mortgage-Related Investments typically represent an interest in a pool of mortgage loans made by banks and other financial institutions. The individual mortgage loans are packaged or “pooled” together for sale to investors. As the underlying mortgage loans are paid off, investors receive principal and interest payments. Mortgage-Related Investments may be fixed-rate or adjustable-rate Mortgage- Related Investments ( ARMS ).

The mortgage-backed securities in which the Fund invests may be, but are not required to be, issued or guaranteed by the U.S. government or its agencies or instrumentalities, such as the Government National Mortgage Association ( “GNMA” ), the Federal National Mortgage Association ( “FNMA” ), and the Federal Home Loan Mortgage Corporation ( “FHLMC” ) (the U.S. government, its agencies and instrumentalities, and U.S. government-sponsored entities are referred to collectively as “ Government Entities ”). The Fund may invest in callable agency securities, which give the issuer the right to redeem the security prior to maturity. The Fund will limit its investments in Mortgage-Related Investments that are not issued or guaranteed by Government Entities to 20% of its net assets (including investment borrowings).

The Fund targets an estimated effective duration of three (3) years or less. Duration is a mathematical calculation of the average life of a debt security (or portfolio of debt securities) that serves as a measure of its price risk. In general, each year of duration represents an expected 1% change in the value of a security for every 1% immediate change in interest rates. For example, if a portfolio of mortgage loans has an average duration of three years, its value can be expected to fall about 3% if interest rates rise by 1%. Conversely, the portfolio’s value can be expected to rise about 3% if interest rates fall by 1%. As a result, prices of instruments with shorter durations tend to be less sensitive to interest rate changes than instruments with longer durations. As the value of a security changes over time, so will its duration. The Fund’s investment advisor will calculate the duration of the portfolio by modeling the cash flows of all the individual holdings, including the impact of prepayment variability and coupon adjustments where applicable, to determine the duration of each holding and then aggregating based on the size of the position. In performing this duration calculation, the Fund’s advisor will utilize third-party models.

The Fund may invest, without limitation, in mortgage dollar rolls. The Fund intends to enter into mortgage dollar rolls only with high quality securities dealers and banks, as determined by the Fund’s investment advisor. In a mortgage dollar roll, the Fund will sell (or buy) mortgage-backed securities for delivery on a specified date and simultaneously contract to repurchase (or sell) substantially similar (same type, coupon and maturity) securities on a future date. The Fund may also invest in to-be-announced transactions ( “TBA Transactions” ). A TBA Transaction is a method of trading mortgage-backed securities. TBA Transactions generally are conducted in accordance with widely-accepted guidelines which establish commonly observed terms and conditions for execution, settlement and delivery. In a TBA Transaction, the buyer and the seller agree on general trade parameters such as agency, settlement date, par amount and price. Further, the Fund may enter into short sales as part of its overall portfolio management strategies or to offset a potential decline in the value of a security; however, the Fund does not expect, under normal market conditions, to engage in short sales with respect to more than 30% of the value of its net assets (including investment borrowings). To the extent required under applicable federal securities laws, rules, and interpretations thereof, the Fund will “set aside” liquid assets or engage in other measures to “cover” open positions and short positions held in connection with the foregoing types of transactions.

Although the Fund intends to invest primarily in investment grade securities, the Fund may invest up to 20% of its net assets (including investment borrowings) in securities of any credit quality, including securities that are below investment grade, which are also known as high yield securities, or commonly referred to as “junk” bonds, or unrated securities that have not been judged by the advisor to be of comparable quality to rated investment grade securities. In the case of a split rating between one or more of the nationally recognized statistical rating organizations, the Fund will consider the highest rating.

Principal Risks

You could lose money by investing in the Fund. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. There can be no assurance that the Fund’s investment objectives will be achieved.

AUTHORIZED PARTICIPANT CONCENTRATION RISK. Only an authorized participant (as defined in the “Frequent Purchases and Redemptions” Section) may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of institutions that act as authorized participants. To the extent that these institutions exit the business or are unable to proceed with creation and/or redemption orders with respect to the Fund and no other authorized participant is able to step forward to create or redeem, in either of these cases, Fund shares may trade at a discount to the Fund’s net asset value and possibly face delisting.

4

CASH TRANSACTIONS RISK. The Fund will, under most circumstances, effect a significant portion of creations and redemptions for cash, rather than in-kind securities. As a result, an investment in the Fund may be less tax-efficient than an investment in an exchange-traded fund that effects its creations and redemptions for in-kind securities. Because the Fund may effect a portion of redemptions for cash, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. A sale of shares may result in capital gains or losses and may also result in higher brokerage costs.

COUNTERPARTY RISK. The Fund bears the risk that the counterparty to mortgage dollar roll, TBA Transaction, derivative or other contract with a third party may default on its obligations or otherwise fail to honor its obligations. If a counterparty defaults on its payment obligations, the Fund will lose money and the value of an investment in Fund shares may decrease. In addition, the Fund may engage in such investment transactions with a limited number of counterparties.

CREDIT RISK. Credit risk is the risk that an issuer of a security will be unable or unwilling to make dividend, interest and/or principal payments when due and the related risk that the value of a security may decline because of concerns about the issuer’s ability to make such payments.

CYBER SECURITY RISK. As the use of Internet technology has become more prevalent in the course of business, the Fund has become more susceptible to potential operational risks through breaches in cyber security. A breach in cyber security refers to both intentional and unintentional events that may cause the Fund to lose proprietary information, suffer data corruption or lose operational capacity. Such events could cause the Fund to incur regulatory penalties, reputational damage, additional compliance costs associated with corrective measures and/or financial loss. Cyber security breaches may involve unauthorized access to the Fund’s digital information systems through “hacking” or malicious software coding, but may also result from outside attacks such as denial-of-service attacks through efforts to make network services unavailable to intended users. In addition, cyber security breaches of the Fund’s third party service providers, such as its administrator, transfer agent, custodian, or sub-advisor, as applicable, or issuers in which the Fund invests, can also subject the Fund to many of the same risks associated with direct cyber security breaches. The Fund has established risk management systems designed to reduce the risks associated with cyber security. However, there is no guarantee that such efforts will succeed, especially because the Fund does not directly control the cyber security systems of issuers or third party service providers.

EXTENSION RISK. Extension risk is the risk that, when interest rates rise, certain obligations will be paid off by the issuer (or obligor) more slowly than anticipated, causing the value of these securities to fall. Rising interest rates tend to extend the duration of securities, making them more sensitive to changes in interest rates. The value of longer-term securities generally changes more in response to changes in interest rates than shorter-term securities. As a result, in a period of rising interest rates, securities may exhibit additional volatility and may lose value.

FLUCTUATION OF NET ASSET VALUE RISK . The net asset value of shares of the Fund will generally fluctuate with changes in the market value of the Fund’s holdings. The market prices of shares will generally fluctuate in accordance with changes in net asset value as well as the relative supply of and demand for shares on the Exchange. The Fund’s investment advisor cannot predict whether shares will trade below, at or above their net asset value because the shares trade on the Exchange at market prices and not at net asset value. Price differences may be due, in large part, to the fact that supply and demand forces at work in the secondary trading market for shares will be closely related to, but not identical to, the same forces influencing the prices of the holdings of the Fund trading individually or in the aggregate at any point in time. However, given that shares can only be purchased and redeemed either in-kind or for cash in Creation Units, and only to and from broker-dealers and large institutional investors that have entered into participation agreements (unlike shares of closed-end funds, which frequently trade at appreciable discounts from, and sometimes at premiums to, their net asset value), the Fund’s investment advisor believes that large discounts or premiums to the net asset value of shares should not be sustained.

HIGH YIELD SECURITIES RISK. High yield securities, or “junk” bonds, are subject to greater market fluctuations and risk of loss than securities with higher ratings, and therefore, are considered to be highly speculative. These securities are issued by companies that may have limited operating history, narrowly focused operations and/or other impediments to the timely payment of periodic interest and principal at maturity. If the economy slows down or dips into recession, the issuers of high yield securities may not have sufficient resources to continue making timely payment of periodic interest and principal at maturity. The market for high yield securities is generally smaller and less liquid than that for investment grade securities. High yield securities are generally not listed on a national securities exchange but trade in the over-the-counter markets. Due to the smaller, less liquid market for high yield securities, the bid-offer spread on such securities is generally greater than it is for investment grade securities and the purchase or sale of such securities may take longer to complete. In general, high yield securities may have a greater risk of default than other types of securities.

5

ILLIQUID SECURITIES RISK. Illiquid securities involve the risk that the securities will not be able to be sold at the time desired by the Fund or at prices approximately the value at which the Fund values the securities.

INCOME RISK. Income from the Fund's fixed income investments could decline during periods of falling interest rates.

INTEREST RATE RISK. Interest rate risk is the risk that the value of the debt securities in the Fund’s portfolio will decline because of rising market interest rates. Interest rate risk is generally lower for shorter term debt securities and higher for longer term debt securities. Duration is a measure of the expected price volatility of a debt instrument as a result of changes in market rates of interest, based on, among other factors, the weighted average timing of the instrument’s expected principal and interest payments. In general, duration represents the expected percentage change in the value of a security for an immediate 1% change in interest rates. Therefore, prices of debt securities with shorter durations tend to be less sensitive to interest rate changes than debt securities with longer durations. As the value of a debt security changes over time, so will its duration. Mortgage-Related Investments are particularly subject to the risk that interest rate volatility may adversely impact the valuation and price of such securities.

LIQUIDITY RISK. The Fund invests a substantial portion of its assets in lower-quality debt issued by companies that are highly leveraged. Lower-quality debt tends to be less liquid than higher-quality debt. Moreover, smaller debt issues tend to be less liquid than larger debt issues. If the economy experiences a sudden downturn, or if the debt markets for such companies become distressed, the Fund may have particular difficulty selling its assets in sufficient amounts, at reasonable prices and in a sufficiently timely manner to raise the cash necessary to meet any potentially heavy redemption requests by Fund shareholders.

MANAGEMENT RISK. The Fund is subject to management risk because it is an actively managed portfolio. In managing the Fund’s investment portfolio, the Fund’s investment advisor will apply investment techniques and risk analyses that may not have the desired result. There can be no guarantee that the Fund will meet its investment objectives.

MARKET MAKER RISK. If the Fund has lower average daily trading volumes, it may rely on a small number of third-party market makers to provide a market for the purchase and sale of shares. Any trading halt or other problem relating to the trading activity of these market makers could result in a dramatic change in the spread between the Fund’s net asset value and the price at which the Fund’s shares are trading on the Exchange, which could result in a decrease in value of the Fund’s shares. In addition, decisions by market makers or authorized participants to reduce their role or step away from these activities in times of market stress could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the underlying values of the Fund’s portfolio securities and the Fund’s market price. This reduced effectiveness could result in Fund shares trading at a discount to net asset value and also in greater than normal intraday bid-ask spreads for Fund shares.

MARKET RISK. Market risk is the risk that a particular security owned by the Fund or shares of the Fund in general may fall in value. Securities are subject to market fluctuations caused by such factors as economic, political, regulatory or market developments, changes in interest rates and perceived trends in securities prices. Shares of the Fund could decline in value or underperform other investments.

MORTGAGE-RELATED INVESTMENTS RISK. The Fund invests in Mortgage-Related Investments, including mortgage-backed securities, which may make the Fund more susceptible to adverse economic, political or regulatory events that affect the value of real estate. Changes in local, state and federal policies could negatively impact the Mortgage-Related Investments market, which include various government initiated and sponsored homeowner assistance programs and eminent domain issues. Mortgage-Related Investments are subject to the risk that the rate of mortgage prepayments decreases, which extends the average life of a security and increases the interest rate exposure. Mortgage-Related Investments may also face liquidity issues when the Fund seeks to sell such securities, but is unable to find buyers at a bid-ask spread to make the transaction feasible. These securities are also subject to the risk that the underlying borrowers may default on their mortgages, resulting in a non-payment of principal and interest. Finally, the Mortgage-Related Investments market may be negatively impacted by regulatory changes including those that are related to the mandate or existence of the government-sponsored enterprises, FNMA, FHLMC and GNMA.

NON-DIVERSIFICATION RISK. The Fund is classified as “non-diversified” under the Investment Company Act of 1940, as amended (the " 1940 Act "). As a result, the Fund is only limited as to the percentage of its assets which may be invested in the securities of any one issuer by the diversification requirements imposed by the Internal Revenue Code of 1986, as amended. The Fund may invest a relatively high percentage of its assets in a limited number of issuers. As a result, the Fund may be more susceptible to a single adverse economic or regulatory occurrence affecting one or more of these issuers, experience increased volatility and be highly invested in certain issuers.

6

PORTFOLIO TURNOVER RISK. The Fund’s strategy may frequently involve buying and selling portfolio securities to rebalance the Fund’s exposure to various market sectors. High portfolio turnover may result in the Fund paying higher levels of transaction costs and generating greater tax liabilities for shareholders. Portfolio turnover risk may cause the Fund’s performance to be less than you expect.

PREPAYMENT RISK. Mortgage-Related Investments are subject to pre-payment risk. The degree to which borrowers prepay loans, whether as a contractual requirement or at their election, may be affected by general business conditions, the financial condition of the borrower and competitive conditions among loan investors, among others. As such, prepayments cannot be predicted with accuracy. Upon a prepayment, either in part or in full, the actual outstanding debt on which the Fund derives interest income will be reduced. The Fund may not be able to reinvest the proceeds received on terms as favorable as the prepaid loan.

REPURCHASE AGREEMENT RISK. The Fund’s investment in repurchase agreements, including mortgage dollar rolls and TBA Transactions, may be subject to market and credit risk with respect to the collateral securing the agreements. Investments in mortgage dollar rolls also may be subject to the risk that the market value of the underlying obligations may decline prior to the expiration of the agreement term.

SHORT SALES RISK. The Fund will incur a loss as a result of a short sale if the price of the security sold short increases in value between the date of the short sale and the date on which the Fund purchases the security to replace the borrowed security. In addition, a lender of a security may request, or market conditions may dictate, that securities sold short be returned to the lender on short notice, which may result in the Fund having to buy the securities sold short at an unfavorable price. If this occurs, any anticipated gain to the Fund may be reduced or eliminated or the short sale may result in a loss. In a rising stock market, the Fund’s short positions may significantly impact the Fund’s overall performance and cause the Fund to underperform traditional long-only equity funds or to sustain losses, particularly in a sharply rising market. The use of short sales may also cause the Fund to have higher expenses than other funds.

Because losses on short sales arise from increases in the value of the security sold short, such losses are theoretically unlimited. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot go below zero. The Fund’s investment advisor’s use of short sales in combination with long positions in the Fund’s portfolio in an attempt to improve performance or reduce overall portfolio risk may not be successful and may result in greater losses or lower positive returns than if the Fund held only long positions. It is possible that the Fund’s long securities positions will decline in value at the same time that the value of its short securities positions increase, thereby increasing potential losses to the Fund. In addition, the Fund’s short selling strategies may limit its ability to fully benefit from increases in the equity markets.

To the extent the Fund invests the proceeds received from selling securities short in additional long positions, the Fund is engaging in a form of leverage. The use of leverage may increase the Fund’s exposure to long positions and make any change in the Fund’s net asset value greater than it would be without the use of leverage. This could result in increased volatility of returns.

TRADING ISSUES RISK . Although the shares of the Fund are listed for trading on the Exchange, there can be no assurance that an active trading market for such shares will develop or be maintained. Trading in shares on the Exchange may be halted due to market conditions or for reasons that, in the view of the Exchange, make trading in shares inadvisable. In addition, trading in shares on the Exchange is subject to trading halts caused by extraordinary market volatility pursuant to the Exchange’s “circuit breaker” rules. Market makers are under no obligation to make a market in the Fund’s shares, and authorized participants are not obligated to submit purchase or redemption orders for Creation Units. There can be no assurance that the requirements of the Exchange necessary to maintain the listing of the Fund will continue to be met or will remain unchanged. In particular, if the Fund does not comply with any provision of the listing standards of the Exchange that are applicable to the Fund, and cannot bring itself into compliance within a reasonable period after discovering the matter, the Exchange may remove the shares of the Fund from listing. The Fund may have difficulty maintaining its listing on the Exchange in the event the Fund’s assets are small or the Fund does not have enough shareholders.

U.S. GOVERNMENT AND AGENCY SECURITIES RISK. U.S. government obligations include U.S. Treasury obligations and securities issued or guaranteed by various agencies of the U.S. government or by various instrumentalities, which have been established or sponsored by the U.S. government. U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. government. Securities issued or guaranteed by federal agencies and U.S. government sponsored instrumentalities may or may not be backed by the full faith and credit of the U.S. government.

7

Annual Total Return

The bar chart and table below illustrate the annual calendar year returns of the Fund based on net asset value as well as the average annual Fund returns. The bar chart and table provide an indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year-to-year and by showing how the Fund’s average annual total returns based on net asset value compared to those of a broad-based securities market index. See “Total Return Information” for additional performance information regarding the Fund. The Fund’s performance information is accessible on the Fund’s website at www.ftportfolios.com.

Returns before taxes do not reflect the effects of any income or capital gains taxes. All after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of any state or local tax. Returns after taxes on distributions reflect the taxed return on the payment of dividends and capital gains. Returns after taxes on distributions and sale of shares assume you sold your shares at period end, and, therefore, are also adjusted for any capital gains or losses incurred. Returns for the market indices do not include expenses, which are deducted from Fund returns, or taxes.

Your own actual after-tax returns will depend on your specific tax situation and may differ from what is shown here. After-tax returns are not relevant to investors who hold Fund shares in tax-deferred accounts such as individual retirement accounts ( IRAs ) or employee-sponsored retirement plans.

First Trust Low Duration Opportunities ETF
Calendar Year Total Returns as of 12/31

During the periods shown in the chart above:

Best Quarter		Worst Quarter
2.16%	March 31, 2016	0.12%	December 31, 2017

The Fund’s past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

Average Annual Total Returns for the Periods Ended December 31, 2017

	1 Year	Since Inception	Inception Date
Return Before Taxes	1.76%	3.94%	11/4/2014
Return After Taxes on Distributions	0.57%	2.67%
Return After Taxes on Distributions and Sale of Shares	0.99%	2.43%
ICE BofAML 1-5 Year US Treasury & Agency Index (1)	0.66%	0.87%

(1)	Effective October 22, 2017, the index name changed from BofA Merrill Lynch 1-5 Year US Treasury & Agency Index to ICE BofAML 1-5 Year US Treasury & Agency Index.

8

9

Additional Information on the Fund's Investment Objectives and Strategies

The Fund’s investment objectives are fundamental and may not be changed without approval by the holders of a majority of the outstanding voting securities of the Fund. Unless an investment policy is identified as being fundamental, all investment policies included in this prospectus and the Fund’s Statement of Additional Information ( “SAI” ) are non- fundamental and may be changed by the Board of Trustees (the “Board” ) of the First Trust Exchange-Traded Fund IV (the “Trust” ), of which the Fund is a series, without shareholder approval. If there is a material change to the Fund’s principal investment strategies, you should consider whether the Fund remains an appropriate investment for you. There is no guarantee that the Fund will achieve its investment objective.

The Fund has adopted a non-fundamental investment policy pursuant to Rule 35d-1 (the “Name Policy” ) under the Investment Company Act of 1940, as amended (the “1940 Act” ), whereby the Fund, under normal market conditions, will invest at least 80% of its net assets (including investment borrowings) in Mortgage-Related Instruments. The Name Policy may be changed by the Board of Trustees without shareholder approval upon 60 days’ prior written notice. If there is a material change to the Fund’s principal investment strategies, you should consider whether the Fund remains an appropriate investment for you. There is no guarantee that the Fund will achieve its investment objectives.

The Fund targets an estimated effective duration of three years or less. In comparison to maturity ( i.e., the date on which a debt instrument ceases and the issuer is obligated to repay the principal amount), duration is a measure of the expected price volatility of a debt instrument as a result of changes in market rates of interest, based on the weighted average timing of the instrument’s expected principal and interest payments and other factors. Duration differs from maturity in that it considers a security’s yield, coupon payments, principal payments, call features and coupon adjustments in addition to the amount of time until the security finally matures. As the value of a security changes over time, so will its duration. Prices of securities with lower durations tend to be less sensitive to interest rate changes than securities with higher durations. In general, a portfolio of securities with a lower duration can be expected to be less sensitive to interest rate changes than a portfolio with a higher duration.

Fund Investments

Principal Investments

Mortgage-Related Investments

The Fund invests in Mortgage-Related Investments. Mortgage-backed securities represent direct or indirect participations in, or are secured by and payable from, mortgage loans secured by real property and can include single- and multi-class pass-through securities and collateralized mortgage obligations. Mortgage-backed securities are based on different types of mortgages, including those on commercial real estate or residential properties. These securities often have stated maturities of up to thirty years when they are issued, depending upon the length of the mortgages underlying the securities.

The Fund generally expects that the Mortgage-Related Investments in which it invests will primarily consist of investment grade securities at the time of purchase. The Mortgage-Related Investments in which the Fund invests include mortgage-backed securities (such as RMBS and CMBS ). Certain mortgage-backed securities (including RMBS and CMBS ), where mortgage payments are divided up between paying the loan’s principal and paying the loan’s interest, are referred to as stripped mortgage-backed securities ( SMBS ). Further, mortgage-backed securities can also be categorized as collateralized mortgage obligations ( CMOs ) or real estate mortgage investment conduits ( REMICs ) where they are divided into multiple classes with each class being entitled to a different share of the principal and/or interest payments received from the pool of underlying assets.

The mortgage-backed securities in which the Fund invests may be, but are not required to be, issued or guaranteed by the U.S. government, its agencies or instrumentalities, such as Ginnie Mae and U.S. government-sponsored entities, such as FNMA and FHLMC. Government agency or instrumentality securities have different levels of credit support. For example, Ginnie Mae securities carry a guarantee as to the timely repayment of principal and interest that is backed by the full faith and credit of the U.S. government. However, the full faith and credit guarantee does not apply to the market prices and yields of the Ginnie Mae securities or to the net asset value, trading price or performance of the Fund, which will vary with changes in interest rates and other market conditions. The FNMA and FHLMC pass-through mortgage certificates are backed by the credit of the respective instrumentality and are not guaranteed by the U.S. government. Other securities issued by government agencies or instrumentalities, including government-sponsored entities, may only be backed by the creditworthiness of the issuing institution, not the U.S. government, or the issuers may have the right to borrow from the U.S. Treasury to meet their obligations.

10

Many mortgage-backed securities are pass-through securities, which means they provide investors with monthly payments consisting of a pro rata share of both regular interest and principal payments as well as unscheduled prepayments on the underlying mortgage loans. Because prepayment rates of individual mortgage pools vary widely, the average life of a particular pool cannot be predicted accurately. Adjustable-rate mortgage-backed securities include ARMS and other mortgage-backed securities with interest rates that adjust periodically to reflect prevailing market rates.

Additionally, the Fund may invest in mortgage dollar rolls. In a mortgage dollar roll, the Fund will sell (or buy) mortgage- backed securities for delivery on a specified date and simultaneously contract to repurchase (or sell) substantially similar (same type, coupon and maturity) securities on a future date. During the period between a sale and repurchase, the Fund will forgo principal and interest paid on the mortgage-backed securities. The Fund will earn or lose money on a mortgage dollar roll from any difference between the sale price and the future purchase price. In a sale and repurchase, the Fund will also earn money on the interest earned on the cash proceeds of the initial sale. The Fund intends to enter into mortgage dollar rolls only with high quality securities dealers and banks, as determined by the Advisor.

The Fund may also invest in TBA Transactions. A TBA Transaction is a method of trading mortgage-backed securities. In a TBA Transaction, the buyer and the seller agree on general trade parameters such as agency, settlement date, par amount and price. The actual pools delivered generally are determined two days prior to the settlement date.

High Yield Debt

The Fund invests primarily in Mortgage-Related Investments, a portion of which may be rated below investment grade, or unrated securities deemed by the Fund’s portfolio managers to be of comparable quality. Securities rated below investment grade are commonly referred to as high yield or “junk” debt. For purposes of determining whether a security is below investment grade, the highest available rating will be considered.

U.S. Government Securities

The Fund may invest in U.S. government securities. U.S. government securities include U.S. Treasury obligations and securities issued or guaranteed by various agencies of the U.S. government, or by various instrumentalities which have been established or sponsored by the U.S. government. U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. government. Securities issued or guaranteed by federal agencies and U.S. government sponsored instrumentalities may or may not be backed by the full faith and credit of the U.S. government.

The Fund may also invest in callable agency securities, which give the issuer (the U.S. government agency) the right to redeem the security prior to maturity. The Fund may also invest in U.S. government inflation-indexed securities.

At times, the Fund may allocate its investments into direct obligations of the U.S. government (such as Treasury bonds, bills and notes) and in securities issued or guaranteed by the U.S. government, its agencies or instrumentalities, including government-sponsored entities.

Non-Principal Investments

Cash Equivalents and Short-Term Investments

Under normal market conditions, the Fund may invest up to 20% of its net assets in short-term debt securities that are not included within the meaning of the term “Mortgage-Related Investments,” such as money market funds and other cash equivalents, or it may hold cash. The percentage of the Fund invested in these types of holdings will vary and will depend on several factors, including market conditions. In addition to its investments in Mortgage-Related Investments issued or guaranteed by Government Entities and in the short-term debt securities described above, the Fund may also invest up to 20% of its net assets (including investment borrowings) in other direct obligations of the U.S. government and in other securities issued or guaranteed by Government Entities. Such investments may include, without limitation, U.S. government inflation-indexed securities.

The Fund may invest in securities with maturities of less than one year or cash equivalents, or it may hold cash, in order to collateralize, its investments or for temporary defensive purposes. The percentage of the Fund invested in these types of holdings varies and depends on several factors, including market conditions. For temporary defensive purposes, during the initial invest-up period and during periods of high cash inflows or outflows, the Fund may depart from its principal investment strategies and invest part or all of its assets in these securities or it may hold cash. During such periods, the Fund may not be able to achieve its investment objective. The Fund may adopt a defensive strategy when the portfolio managers believe

11

securities in which the Fund normally invests have elevated risks due to political or economic factors and in other extraordinary circumstances. For more information on eligible short-term investments, see the Fund’s SAI.

Derivative Instruments

Consistent with an exemptive order from, and no-action letters issued by, the Securities and Exchange Commission, the Fund may use exchange listed options on U.S. Treasury securities, exchange listed options on U.S. Treasury futures contracts and exchange-listed U.S. Treasury futures contracts. The use of these derivative transactions may allow the Fund to obtain net long or short exposures to selected interest rates or durations. The Fund may also utilize derivatives to enhance return, to hedge some of the risks of its investments in securities, as a substitute for a position in the underlying asset, to reduce transaction costs, to maintain full market exposure (which means to adjust the characteristics of its investments to more closely approximate those of the markets in which it invests), to manage cash flows, to limit exposure to losses due to changes to non-U.S. currency exchange rates or to preserve capital.

Illiquid Securities

The Fund may invest up to 15% of its net assets in securities and other instruments that are, at the time of investment, illiquid (determined using the Securities and Exchange Commission’s standard applicable to investment companies, i.e. , securities that cannot be disposed of by the Fund within seven days in the ordinary course of business at approximately the amount at which the Fund has valued the securities). For this purpose, illiquid securities may include, but are not limited to, restricted securities (securities the disposition of which is restricted under the federal securities laws), securities that may only be resold pursuant to Rule 144A under the Securities Act of 1933, as amended (the “Securities Act” ), that are deemed to be illiquid, and certain repurchase agreements.

Investment Companies and Other Pooled Investment Vehicles

Although it is not a part of the Fund’s principal investment strategies, the Fund may invest in securities of other investment companies, including exchange-traded funds (“ ETFs ”) that invest primarily in Mortgage-Related Investments and, except for these investments in other investment companies, the Fund will not invest directly in equity securities. ETFs trade on a securities exchange and their shares may, at times, trade at a premium or discount to their net asset value. As a stockholder in an investment company or other pooled vehicle, the Fund will bear its ratable share of that investment company’s or vehicle’s expenses, and would remain subject to payment of the Fund’s or vehicle’s advisory and administrative fees with respect to assets so invested.

The Fund's ability to invest in other investment companies is limited by the 1940 Act and the related rules and interpretations. The Fund has adopted a policy that it will not invest in other investment companies in excess of 1940 Act limits in reliance on Sections 12(d)(1)(F) and 12(d)(1)(G) of the 1940 Act.

Disclosure of Portfolio Holdings

A description of the policies and procedures with respect to the disclosure of the Fund’s portfolio securities is included in the Fund’s SAI, which is available on the Fund’s website at www.ftportfolios.com.

Additional Risks of Investing in the Fund

Risk is inherent in all investing. Investing in the Fund involves risk, including the risk that you may lose all or part of your investment. There can be no assurance that the Fund will meet its stated objectives. Before you invest, you should consider the following supplemental disclosure pertaining to the Principal Risks set forth above as well as additional Non-Principal Risks set forth below in this prospectus.

Principal Risks

CASH TRANSACTIONS RISK. The Fund intends to effect a significant portion of creations and redemptions for cash, rather than in-kind securities. As a result, an investment in the Fund may be less tax-efficient than an investment in an ETF that effects its creations and redemptions for in-kind securities. ETFs are able to make in-kind redemptions and avoid being taxed on gains on the distributed portfolio securities at the fund level. Because the Fund intends to effect a significant portion of redemptions for cash, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. Any recognized gain on these sales by the Fund will generally cause the Fund to recognize a gain it might not otherwise have recognized, or to recognize such gain sooner than would otherwise be required if it were to distribute portfolio securities in-kind. The Fund intends to distribute these gains to shareholders to avoid being taxed on this gain at the fund level and

12

otherwise comply with the special tax rules that apply to it. This strategy may cause shareholders to be subject to tax on gains they would not otherwise be subject to, or at an earlier date than if they had made an investment in a different ETF. Moreover, cash transactions may have to be carried out over several days if the securities market is relatively illiquid, and such transactions may involve considerable brokerage fees and taxes. These brokerage fees and taxes, which will be higher than if the Fund sold and redeemed its shares principally in-kind, will be passed on to those purchasing and redeeming Creation Units in the form of creation and redemption transaction fees. In addition, these factors may result in wider spreads between the bid and the offered prices of the Fund's shares than for ETFs that distribute portfolio securities in-kind.

COUNTERPARTY RISK. The Fund intends to engage in investment transactions or enter into contracts with third parties ( i.e.,“counterparties” ), including mortgage dollar rolls and TBA Transactions. The Fund bears the risk that the counterparty to such contracts may default on its obligations or otherwise fail to honor its obligations. If a counterparty defaults on its payment obligations the Fund will lose money and the value of an investment in Fund shares may decrease. In addition, the Fund may engage in such investment transactions with a limited number of counterparties, which may increase the Fund’s exposure to counterparty credit risk.

CREDIT RISK. An issuer of a debt instrument may be unable or unwilling to make dividend, interest and/or principal payments when due and the related risk that the value of a debt instrument may decline because of concerns about the issuer’s ability or unwillingness to make such payments. High yield and comparable unrated debt securities, while generally offering higher yields than investment grade debt with similar maturities, involve greater risks, including the possibility of dividend or interest deferral, default or bankruptcy, and are regarded as predominantly speculative with respect to the issuer’s capacity to pay dividends or interest and repay principal. Credit risk is heightened for loans in which the Fund invests because companies that issue such loans tend to be highly leveraged and thus are more susceptible to the risks of interest deferral, default and/or bankruptcy.

HIGH YIELD SECURITIES RISK. The Fund's investment in high yield, high risk obligations or “junk” bonds, may entail increased credit risks and the risk that the value of the Fund’s assets will decline, and may decline precipitously, with increases in interest rates. In recent years there have been wide fluctuations in interest rates and thus in the value of fixed-rate obligations generally. Securities such as those included in the Fund are, under most circumstances, subject to greater market fluctuations and risk of loss of income and principal than are investments in lower-yielding, higher-rated securities, and their value may decline precipitously because of increases in interest rates, not only because the increases in rates generally decrease values, but also because increased rates may indicate a slowdown in the economy and a decrease in the value of assets generally that may adversely affect the credit of issuers of high yield, high risk securities resulting in a higher incidence of defaults among high yield, high risk securities. A slowdown in the economy , or a development adversely affecting an issuer’s creditworthiness, may result in the issuer being unable to maintain earnings or sell assets at the rate and at the prices, respectively, that are required to produce sufficient cash flow to meet its interest and principal requirements. For an issuer that has outstanding both senior commercial bank debt and subordinated high yield, high risk securities, an increase in interest rates will increase that issuer’s interest expense insofar as the interest rate on the bank debt is fluctuating. However, many leveraged issuers enter into interest rate protection agreements to fix or cap the interest rate on a large portion of their bank debt. This reduces exposure to increasing rates, but reduces the benefit to the issuer of declining rates. The Advisor cannot predict future economic policies or their consequences or, therefore, the course or extent of any similar market fluctuations in the future.

High yield debt may be issued by companies without long track records of sales and earnings, or by issuers that have questionable credit strength. High yield debt and comparable unrated debt securities: (a) will likely have some quality and protective characteristics that, in the judgment of the rating agency evaluating the instrument, are outweighed by large uncertainties or major risk exposures to adverse conditions; and (b) are predominantly speculative with respect to the issuer’s capacity to pay dividends or interest and repay principal in accordance with the terms of the obligation. Many lower-quality debt securities are subject to legal or contractual restrictions limiting the Fund's ability to resell the securities to the general public.

ILLIQUID SECURITIES RISK. The Fund may invest a substantial portion of its assets in lower-quality mortgage-backed securities. Lower-quality securities tend to be less liquid than higher-quality securities. If the economy experiences a sudden downturn, or if the debt markets for such issuers become distressed, the Fund may have particular difficulty selling its assets in sufficient amounts, at reasonable prices and in a sufficiently timely manner to raise the cash necessary to meet any potentially heavy redemption requests by Fund shareholders. In such event, there would be a greater chance that the Fund may be forced to curtail or suspend redemptions, in which case you might experience a delay or inability to liquidate your investment at the desired time or in the desired amount.

13

INCOME RISK. The Fund’s income could decline due to falling market interest rates. This is because, in a falling interest rate environment, the Fund generally will have to invest the proceeds from sales of Fund shares, as well as the proceeds from maturing portfolio securities, or portfolio securities that have been called, in lower-yielding securities.

INTEREST RATE RISK. The value of the Fund’s debt securities will fluctuate in value with changes in interest rates. In general, debt securities will increase in value when interest rates fall and decrease in value when interest rates rise. The Fund may be subject to a greater risk of rising interest rates than would normally be the case due to the current period of historically low rates and the effect of potential government fiscal policy initiatives and resulting market reaction to those initiatives.

Interest rate risk is generally lower for shorter term investments and higher for longer term investments. Duration is a common measure of interest rate risk. Duration measures a debt security’s expected life on a present value basis, taking into account the debt security’s yield, interest payments and final maturity. Duration is a reasonably accurate measure of a debt security’s price sensitivity to changes in interest rates. The longer the duration of a debt security, the greater the debt security’s price sensitivity is to changes in interest rates. Rising interest rates also may lengthen the duration of debt securities with call features, since exercise of the call because less likely as interest rates rise, which in turn will make the securities more sensitive to changes in interest rates and result in even steeper price declines in the event of further interest rate increases.

An increase in interest rates could also cause principal payments on a debt security to be repaid at a slower rate than expected. This risk is particularly prevalent for a callable security where an increase in interest rates could cause the issuer of that security to not redeem the security as anticipated on the call date, which could have the effect of lengthening that debt security’s expected maturity, in turn making that security more vulnerable to interest rate risk and reducing its market value.

When interest rates fall, the Fund may be required to reinvest the proceeds from the sale, redemption or early prepayment of a debt security at a lower interest rate.

MARKET RISK. The market values of the Fund’s investments may decline, at times sharply and unpredictably. Market values of debt securities are affected by a number of different factors, including changes in interest rates, the credit quality of bond issuers, and general economic and market conditions.

SHORT SALES RISK. Short sales involve the sale of a security the Fund has borrowed, with the expectation that the security will underperform the market. Short sales expose the Fund to the risk that it will be required to buy the security sold short (also known as “covering” the short position) at a time when the security has appreciated in value, thus resulting in a loss to the Fund. For instance, the lender of the borrowed security may recall the security, in which case the Fund would have to either borrow the security from another lender or buy the security and deliver it to the lender. The Fund may not always be able to locate another lender, and thus the Fund may be required to cover the short position at a disadvantageous price. Although the gain is limited by the price at which the security was sold short, the potential loss on a short sale is theoretically unlimited because there is no upper limit on the price a borrowed security can attain. In a rising stock market, the Fund’s short positions may significantly impact the Fund’s overall performance and cause the Fund to underperform traditional long-only equity funds or to sustain losses, particularly in a sharply rising market. Short positions are more volatile than long positions due to risks inherent to short selling, including incorrect determinations of equity security valuations and/or the directional movement of stock market averages. The Fund may also pay transaction costs and borrowing fees in connection with short sales. In addition, short positions typically involve increased liquidity risk and the risk that the third party to the short sale may fail to honor its contract terms. To the extent the Fund invests the proceeds received from selling securities short in additional long positions, the Fund is engaging in a form of leverage that may magnify gains or losses for the Fund.

In the past, in response to market events, regulatory authorities in various countries, including the United States, enacted temporary rules prohibiting the short-selling of certain stocks. If regulatory authorities were to reinstitute such rules or otherwise restrict short-selling, the Fund might not be able to fully implement its short-selling strategy.

Non-Principal Risks

BORROWING AND LEVERAGE RISK. If the Fund borrows money, it must pay interest and other fees, which may reduce the Fund’s returns . Any such borrowings are intended to be temporary. However, under certain market conditions, including periods of low demand or decreased liquidity, such borrowings might be outstanding for longer periods of time. As prescribed by the 1940 Act, the Fund will be required to maintain specified asset coverage of at least 300% with respect to any bank borrowing immediately following such borrowing. The Fund may be required to dispose of assets on unfavorable terms if market fluctuations or other factors reduce the Fund’s asset coverage to less than the prescribed amount.

14

CREDIT RATING AGENCY RISK. Credit ratings are determined by credit rating agencies such as S&P, Moody’s and Fitch, and are only the opinions of such entities. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risk or the liquidity of securities. Any shortcomings or inefficiencies in credit rating agencies’ processes for determining credit ratings may adversely affect the credit ratings of securities held by the Fund and, as a result, may adversely affect those securities’ perceived or actual credit risk.

DEPENDENCE ON KEY PERSONNEL. The Advisor is dependent upon the experience and expertise of the Fund’s portfolio managers in providing advisory services with respect to the Fund’s investments. If the Advisor were to lose the services of any of these portfolio managers, its ability to service the Fund could be adversely affected. There can be no assurance that a suitable replacement could be found for any of the portfolio managers in the event of their death, resignation, retirement or inability to act on behalf of the Advisor.

DERIVATIVES RISK. The use of derivative instruments, including exchange-listed options on U.S. Treasury securities, exchange-listed options on U.S. Treasury futures contracts and exchange-listed U.S. Treasury futures contracts involves additional risks and transaction costs that could leave the Fund in a worse position than if it had not used these instruments. Derivatives may entail investment exposures that are greater than their cost would suggest. As a result, a small investment in derivatives can result in losses that greatly exceed the original investment.

Derivatives can be highly volatile, illiquid and difficult to value, and there is the risk that changes in the value of a derivative held by a Fund will not correlate with the asset, index or rate underlying the derivative contract. In addition, when the Fund invests in certain derivative securities, it is effectively leveraging its investments, which could result in exaggerated changes in the net asset value of the Fund’s shares and can result in losses that exceed the amount originally invested. The success of the portfolio managers' derivatives strategies will depend on their ability to assess and predict the impact of market or economic developments on the underlying asset, index or rate and the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions. Liquidity risk exists when a security cannot be purchased or sold at the time desired, or cannot be purchased or sold without adversely affecting the price.

FAILURE TO QUALIFY AS A REGULATED INVESTMENT COMPANY. If, in any year, the Fund fails to qualify as a regulated investment company under the applicable tax laws, the Fund would be taxed as an ordinary corporation. In such circumstances, the Fund could be required to recognize unrealized gains, pay substantial taxes and interest and make substantial distributions before requalifying as a regulated investment company that is accorded special tax treatment. If the Fund fails to qualify as a regulated investment company, distributions to the Fund’s shareholders generally would be eligible for the dividends received deduction in the case of corporate shareholders. See “Federal Tax Matters.”

INFLATION RISK. Inflation risk is the risk that the value of assets or income from investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund’s assets can decline as can the value of the Fund’s distributions.

INVESTMENT COMPANIES RISK. The Fund may invest in securities of other investment companies, including ETFs. As a shareholder in other investment companies, the Fund will bear its ratable share of that investment company’s expenses, and would remain subject to payment of the Fund’s advisory and administrative fees with respect to assets so invested. Shareholders would therefore be subject to duplicative expenses to the extent the Fund invests in other investment companies. In addition, the Fund will incur brokerage costs when purchasing and selling shares of ETFs or other exchange-traded investment companies.

ISSUER SPECIFIC CHANGES RISK. The value of an individual security or particular type of security can be more volatile than the market as a whole and can perform differently from the value of the market as a whole.

LEGISLATION/LITIGATION RISK. From time to time, various legislative initiatives are proposed in the United States and abroad, which may have a negative impact on certain companies in which the Fund invests. In addition, litigation regarding any of the issuers of the securities owned by the Fund, or industries represented by these issuers, may negatively impact the value of the securities. Such legislation or litigation may cause the Fund to lose value or may result in higher portfolio turnover if the Advisor determines to sell such a holding.

VALUATION RISK. Unlike publicly traded securities that trade on national exchanges, there is no central place or exchange for fixed income securities trading. Fixed income securities generally trade on an “over-the-counter” market which may be anywhere in the world where the buyer and seller can settle on a price. Due to the lack of centralized information and trading, the valuation of fixed income securities may carry more uncertainty and risk than that of publicly traded securities. Accordingly, determinations of the fair value of fixed income securities may be based on infrequent and dated information. Also, because the available information is less reliable and more subjective, elements of judgment may play a greater role in valuation of

15

fixed income securities than for other types of securities. Typically, Fixed income securities are valued using information provided by a third-party pricing service, which primarily uses broker quotes to value the securities.

Fund Organization

The Fund is a series of the Trust, an investment company registered under the 1940 Act. The Fund is treated as a separate fund with its own investment objectives and policies. The Trust is organized as a Massachusetts business trust. The Trust's Board is responsible for the overall management and direction of the Trust. The Board elects the Trust’s officers and approves all significant agreements, including those with the investment advisor, custodian and fund administrative and accounting agent.

Management of the Fund

First Trust Advisors L.P., 120 East Liberty Drive, Wheaton, Illinois 60187, is the investment advisor to the Fund. In this capacity, First Trust is responsible for the selection and ongoing monitoring of the securities in the Fund’s portfolio and certain other services necessary for the management of the portfolio.

First Trust is a limited partnership with one limited partner, Grace Partners of DuPage L.P., and one general partner, The Charger Corporation. Grace Partners of DuPage L.P. is a limited partnership with one general partner, The Charger Corporation, and a number of limited partners. The Charger Corporation is an Illinois corporation controlled by James A. Bowen, the Chief Executive Officer of First Trust. First Trust discharges its responsibilities subject to the policies of the Board.

First Trust serves as advisor or sub-advisor for seven mutual fund portfolios, 10 exchange-traded funds consisting of 130 series and 16 closed-end funds. It is also the portfolio supervisor of certain unit investment trusts sponsored by First Trust Portfolios L.P. (“ FTP ”), an affiliate of First Trust, 120 East Liberty Drive, Wheaton, Illinois 60187. FTP specializes in the underwriting, trading and distribution of unit investment trusts and other securities. FTP is the principal underwriter of the shares of the Fund.

Jim Snyder and Jeremiah Charles are the Fund’s portfolio managers and are jointly and primarily responsible for the day- to-day management of the Fund’s investment portfolio.

•

Jim Snyder is a Portfolio Manager for the First Trust Mortgage Securities Team. Prior to joining First Trust in 2013, Mr. Snyder worked as a Senior Portfolio Manager at Fort Sheridan Advisors where he managed mortgage portfolios for institutional clients. Mr. Snyder has led several mortgage trading and portfolio groups at Deerfield Capital, Spyglass Capital & Trading and American Express Financial Advisors. Mr. Snyder managed AXP Federal Income Fund, and developed mortgage trading strategies for Spyglass Capital and Deerfield’s Mortgage REIT and Opportunity Fund. Mr. Snyder holds a B.S. and M.A. in Economics from DePaul University and an MBA from University of Chicago Booth School of Business.

•

Jeremiah Charles is a Portfolio Manager for the First Trust Mortgage Securities Team. Prior to joining First Trust in 2013, Mr. Charles worked as a Vice President of Mortgage Product Sales for CRT Capital where he advised pension funds, hedge funds, and institutional money managers. Before joining CRT in 2011, Mr. Charles spent 6 years with Deerfield Capital Management LLC as a Senior Vice President and Senior Portfolio Manager for the Mortgage Trading team. Mr. Charles began his professional career as an Analyst at Piper Jaffray. Mr. Charles holds a B.S. in Finance from the Leeds School of Business at the University of Colorado, and a M.S. in Real Estate Finance with Honors from the Charles H. Kellstadt Graduate School of Business at DePaul University.

For additional information concerning First Trust, including a description of the services provided to the Fund, see the Fund’s SAI. Additional information about the portfolio managers’ compensation, other accounts managed by the portfolio managers and the portfolio managers’ ownership of shares of the Fund is provided in the SAI.

Management Fee

Pursuant to the Investment Management Agreement, First Trust is paid an annual management fee of 0.65% of the Fund’s average daily net assets and is responsible for the Fund’s expenses, including the cost of transfer agency, custody, fund administration, legal, audit and other services, but excluding fee payments under the Investment Management Agreement, interest, taxes, acquired fund fees and expenses, if any, brokerage commissions and other expenses connected with the execution of portfolio transactions, distribution and service fees pursuant to a Rule 12b-1 plan, if any, and extraordinary expenses.

16

A discussion regarding the Board’s approval of the continuation of the Investment Management Agreement is available in the Fund’s Annual Report to shareholders for the fiscal period ended October 31, 2017.

How to Buy and Sell Shares

Most investors will buy and sell shares of the Fund in secondary market transactions through brokers. Shares of the Fund are listed for trading on the secondary market on Nasdaq. Shares can be bought and sold throughout the trading day like other publicly traded shares. There is no minimum investment when buying shares on Nasdaq. Although shares are generally purchased and sold in “round lots” of 100 shares, brokerage firms typically permit investors to purchase or sell shares in smaller “odd lots,” at no per-share price differential. When buying or selling shares through a broker, investors should expect to incur customary brokerage commissions, investors may receive less than the net asset value of the shares because shares are bought and sold at market prices rather than net asset value and investors may pay some or all of the spread between the bid and the offer price in the secondary market on each leg of a round trip (purchase and sale) transaction. Share prices are reported in dollars and cents per share.

For purposes of the 1940 Act, the Fund is treated as a registered investment company, and, absent an available exemption or exemptive relief, the acquisition of shares by other registered investment companies and companies relying on Sections 3(c)(1) or 3(c)(7) of the 1940 Act is subject to the restrictions of Section 12(d)(1) of the 1940 Act. The Trust, on behalf of the Fund, has received an exemptive order from the Securities and Exchange Commission that permits certain registered investment companies to invest in the Fund beyond the limits set forth in Section 12(d)(1), subject to certain terms and conditions, including that any such investment companies enter into an agreement with the Fund regarding the terms of any investment.

Book Entry

Shares are held in book-entry form, which means that no share certificates are issued. The Depository Trust Company ( “DTC” ) or its nominee is the record owner of all outstanding shares of the Fund and is recognized as the owner of all shares for all purposes.

Investors owning shares are beneficial owners as shown on the records of DTC or its participants. DTC serves as the securities depository for all shares. Participants in DTC include securities brokers and dealers, banks, trust companies, clearing corporations and other institutions that directly or indirectly maintain a custodial relationship with DTC. As a beneficial owner of shares, you are not entitled to receive physical delivery of share certificates or to have shares registered in your name, and you are not considered a registered owner of shares. Therefore, to exercise any right as an owner of shares, you must rely upon the procedures of DTC and its participants. These procedures are the same as those that apply to any other stocks that you hold in book-entry or “street name” form.

Share Trading Prices

The trading price of shares of the Fund on Nasdaq is based on market price and may differ from the Fund’s daily net asset value and can be affected by market forces of supply and demand, economic conditions and other factors.

Information regarding the intra-day value of the shares of the Fund, also referred to as the “indicative optimized portfolio value” ( “IOPV” ), is disseminated every 15 seconds throughout the Fund’s trading day by the national securities exchange on which the shares are listed or by market data vendors or other information providers. The IOPV should not be viewed as a “real-time” update of the net asset value per share of the Fund because the IOPV may not be calculated in the same manner as the net asset value, which is computed once a day, generally at the end of the business day. The price of a non-U.S. security that is primarily traded on a non-U.S. exchange shall be updated, using the last sale price, every 15 seconds throughout the trading day, provided that upon the closing of such non-U.S. exchange, the closing price of the security, after being converted to U.S. dollars, will be used. Furthermore, in calculating the IOPV of the Fund’s shares, exchange rates may be used throughout the day (9:00 a.m. to 4:15 p.m., Eastern time) that may differ from those used to calculate the net asset value per share of the Fund and consequently may result in differences between the net asset value and the IOPV. The Fund is not involved in, or responsible for, the calculation or dissemination of the IOPV of shares of the Fund and the Fund does not make any warranty as to its accuracy.

Frequent Purchases and Redemptions of the Fund’s Shares

The Fund imposes no restrictions on the frequency of purchases and redemptions ( “market timing” ). In determining not to approve a written, established policy, the Board evaluated the risks of market timing activities by the Fund’s shareholders.

17

The Board considered that the Fund’s shares can only be purchased and redeemed directly from the Fund in Creation Units by broker-dealers and large institutional investors that have entered into participation agreements ( i.e ., authorized participants ( “APs” )) and that the vast majority of trading in the Fund’s shares occurs on the secondary market. Because the secondary market trades do not involve the Fund directly, it is unlikely those trades would cause many of the harmful effects of market timing, including dilution, disruption of portfolio management, increases in the Fund’s trading costs and the realization of capital gains. With respect to trades directly with the Fund, to the extent effected in-kind ( i.e ., for securities), those trades do not cause any of the harmful effects that may result from frequent cash trades. To the extent that the Fund may effect the purchase or redemption of Creation Units in exchange wholly or partially for cash, the Board noted that such trades could result in dilution to the Fund and increased transaction costs, which could negatively impact the Fund’s ability to achieve its investment objectives. However, the Board noted that direct trading by APs is critical to ensuring that the shares trade at or close to net asset value. In addition, the Fund imposes fixed and variable transaction fees on purchases and redemptions of Creation Units to cover the custodial and other costs incurred by the Fund in effecting trades. Finally, the Advisor monitors purchase and redemption orders from APs for patterns of abusive trading and the Fund reserves the right to not accept orders from APs that the Advisor has determined may be disruptive to the management of the Fund, or otherwise not in the Fund’s best interests.

Dividends, Distributions and Taxes

Dividends from net investment income, if any, are declared and paid monthly by the Fund. The Fund distributes its net realized capital gains, if any, to shareholders at least annually.

Distributions in cash may be reinvested automatically in additional whole shares only if the broker through whom you purchased shares makes such option available. Such shares will generally be reinvested by the broker based upon the market price of those shares and investors may be subject to customary brokerage commissions charged by the broker.

Federal Tax Matters

This section summarizes some of the main U.S. federal income tax consequences of owning shares of the Fund. This section is current as of the date of this prospectus. Tax laws and interpretations change frequently, and these summaries do not describe all of the tax consequences to all taxpayers. For example, these summaries generally do not describe your situation if you are a corporation, a non-U.S. person, a broker-dealer or other investor with special circumstances. In addition, this section does not describe your state, local or non-U.S. tax consequences.

This federal income tax summary is based in part on the advice of counsel to the Fund. The Internal Revenue Service could disagree with any conclusions set forth in this section. In addition, counsel to the Fund was not asked to review, and has not reached a conclusion with respect to, the federal income tax treatment of the assets to be included in the Fund. This may not be sufficient for you to use for the purpose of avoiding penalties under federal tax law.

As with any investment, you should seek advice based on your individual circumstances from your own tax advisor.

Fund Status

The Fund intends to continue to qualify or qualify as a “regulated investment company” under the federal tax laws. If the Fund qualifies as a regulated investment company and distributes its income as required by the tax law, the Fund generally will not pay federal income taxes.

Distributions

The Fund’s distributions are generally taxable. After the end of each year, you will receive a tax statement that separates the distributions of the Fund into two categories: ordinary income distributions and capital gain dividends. Ordinary income distributions are generally taxed at your ordinary tax rate. Generally, you will treat all capital gain dividends as long-term capital gains regardless of how long you have owned your shares. To determine your actual tax liability for your capital gain dividends, you must calculate your total net capital gain or loss for the tax year after considering all of your other taxable transactions, as described below. In addition, the Fund may make distributions that represent a return of capital for tax purposes and thus will generally not be taxable to you; however, such distributions may reduce your tax basis in your shares, which could result in you having to pay higher taxes in the future when shares are sold, even if you sell the shares at a loss from your original investment. The tax status of your distributions from the Fund is not affected by whether you reinvest your distributions in additional shares or receive them in cash. The income from the Fund that you must take into account for federal income tax

18

purposes is not reduced by amounts used to pay a deferred sales fee, if any. The tax laws may require you to treat distributions made to you in January as if you had received them on December 31 of the previous year.

Income from the Fund may also be subject to a 3.8% “Medicare tax.” This tax generally applies to your net investment income if your adjusted gross income exceeds certain threshold amounts, which are $250,000 in the case of married couples filing joint returns and $200,000 in the case of single individuals.

Dividends Received Deduction

A corporation that owns shares generally will not be entitled to the dividends received deduction with respect to dividends received from the Fund because the dividends received deduction is generally not available for distributions from regulated investment companies.

Capital Gains and Losses

If you are an individual, the maximum marginal stated federal tax rate for net capital gain is generally 20% (15% or 0% for taxpayers with taxable incomes below certain thresholds). Some portion of your capital gain dividends may be taxed at a higher maximum stated tax rate. Capital gains may also be subject to the Medicare tax described above.

Net capital gain equals net long-term capital gain minus net short-term capital loss for the taxable year. Capital gain or loss is long-term if the holding period for the asset is more than one year and is short-term if the holding period for the asset is one year or less. You must exclude the date you purchase your shares to determine your holding period. However, if you receive a capital gain dividend from the Fund and sell your shares at a loss after holding it for six months or less, the loss will be recharacterized as long-term capital loss to the extent of the capital gain dividend received. The tax rates for capital gains realized from assets held for one year or less are generally the same as for ordinary income. The Internal Revenue Code of 1986, as amended, treats certain capital gains as ordinary income in special situations.

Sale of Shares

If you sell or redeem your shares, you will generally recognize a taxable gain or loss. To determine the amount of this gain or loss, you must subtract your tax basis in your shares from the amount you receive in the transaction. Your tax basis in your shares is generally equal to the cost of your shares, generally including sales charges. In some cases, however, you may have to adjust your tax basis after you purchase your shares.

Taxes on Purchase and Redemption of Creation Units

If you exchange securities for Creation Units you will generally recognize a gain or a loss. The gain or loss will be equal to the difference between the market value of the Creation Units at the time and your aggregate basis in the securities surrendered and the cash component paid. If you exchange Creation Units for securities, you will generally recognize a gain or loss equal to the difference between your basis in the Creation Units and the aggregate market value of the securities received and the cash redemption amount. The Internal Revenue Service, however, may assert that a loss realized upon an exchange of securities for Creation Units or Creation Units for securities cannot be deducted currently under the rules governing “wash sales,” or on the basis that there has been no significant change in economic position.

Treatment of Fund Expenses

Expenses incurred and deducted by the Fund will generally not be treated as income taxable to you. In some cases, however, you may be required to treat your portion of these Fund expenses as income. You may not be able to deduct some or all of these expenses.

Non-U.S. Tax Credit

Because the Fund invests in non-U.S. securities, the tax statement that you receive may include an item showing non-U.S. taxes the Fund paid to other countries. In this case, dividends taxed to you will include your share of the taxes the Fund paid to other countries. You may be able to deduct or receive a tax credit for your share of these taxes.

Non-U.S. Investors

If you are a non-U.S. investor ( i.e. , an investor other than a U.S. citizen or resident or a U.S. corporation, partnership, estate or trust), you should be aware that, generally, subject to applicable tax treaties, distributions from the Fund will be characterized as dividends for federal income tax purposes (other than dividends which the Fund properly reports as capital gain dividends) and will be subject to U.S. federal income taxes, including withholding taxes, subject to certain exceptions described below.

19

However, distributions received by a non-U.S. investor from the Fund that are properly reported by the Fund as capital gain dividends may not be subject to U.S. federal income taxes, including withholding taxes, provided that the Fund makes certain elections and certain other conditions are met. Distributions from the Fund that are properly reported by the Fund as an interest-related dividend attributable to certain interest income received by the Fund or as a short-term capital gain dividend attributable to certain net short-term capital gain income received by the Fund may not be subject to U.S. federal income taxes, including withholding taxes when received by certain non-U.S. investors, provided that the Fund makes certain elections and certain other conditions are met.

Distributions may be subject to a U.S. withholding tax of 30% in the case of distributions to (i) certain non-U.S. financial institutions that have not entered into an agreement with the U.S. Treasury to collect and disclose certain information and are not resident in a jurisdiction that has entered into such an agreement with the U.S. Treasury and (ii) certain other non-U.S. entities that do not provide certain certifications and information about the entity’s U.S. owners. Disposition of shares by such persons may be subject to such withholding after December 31, 2018.

Distribution Plan

FTP serves as the distributor of Creation Units for the Fund on an agency basis. FTP does not maintain a secondary market in shares.

The Board has adopted a Distribution and Service Plan pursuant to Rule 12b-1 under the 1940 Act. In accordance with the Rule 12b-1 plan, the Fund is authorized to pay an amount up to 0.25% of its average daily net assets each year to reimburse FTP for amounts expended to finance activities primarily intended to result in the sale of Creation Units or the provision of investor services. FTP may also use this amount to compensate securities dealers or other persons that are APs for providing distribution assistance, including broker-dealer and shareholder support and educational and promotional services.

The Fund does not currently pay 12b-1 fees, and pursuant to a contractual arrangement, the Fund will not pay 12b-1 fees any time before March 31, 2019. However, in the event 12b-1 fees are charged in the future, because these fees are paid out of the Fund's assets, over time these fees will increase the cost of your investment and may cost you more than certain other types of sales charges.

Net Asset Value

The Fund’s net asset value is determined as of the close of trading (normally 4:00 p.m., Eastern time) on each day the New York Stock Exchange is open for business. Net asset value is calculated for the Fund by taking the market price of the Fund’s total assets, including interest or dividends accrued but not yet collected, less all liabilities, and dividing such amount by the total number of shares outstanding. The result, rounded to the nearest cent, is the net asset value per share. All valuations are subject to review by the Board or its delegate.

The Fund’s investments are valued daily in accordance with valuation procedures adopted by the Board, and in accordance with provisions of the 1940 Act. Certain securities in which the Fund may invest are not listed on any securities exchange or board of trade. Such securities are typically bought and sold by institutional investors in individually negotiated private transactions that function in many respects like an over-the-counter secondary market, although typically no formal market makers exist. Certain securities, particularly debt securities, have few or no trades, or trade infrequently, and information regarding a specific security may not be widely available or may be incomplete. Accordingly, determinations of the fair value of debt securities may be based on infrequent and dated information. Because there is less reliable, objective data available, elements of judgment may play a greater role in valuation of debt securities than for other types of securities. Typically, debt securities are valued using information provided by a third-party pricing service. The third-party pricing service primarily uses broker quotes to value the securities.

The Fund’s investments are valued daily at market value or, in the absence of market value with respect to any portfolio securities, at fair value in accordance with valuation procedures adopted by the Board and in accordance with the 1940 Act. Portfolio securities listed on any exchange other than Nasdaq and the London Stock Exchange Alternative Investment Market ( “AIM” ) are valued at the last sale price on the business day as of which such value is being determined. Securities listed on Nasdaq or the AIM are valued at the official closing price on the business day as of which such value is being determined. If there has been no sale on such day, or no official closing price in the case of securities traded on Nasdaq or the AIM, the securities are fair valued at the mean of the most recent bid and ask prices on such day. Portfolio securities traded on more than one securities exchange are valued at the last sale price or official closing price, as applicable, on the business day as of which such value is being determined at the close of the exchange representing the principal market for such securities. Portfolio securities

20

traded in the over-the-counter market, but excluding securities trading on Nasdaq or the AIM, are fair valued at the mean of the most recent bid and asked price, if available, and otherwise at the closing bid price. Short-term investments that mature in less than 60 days when purchased are fair valued at cost adjusted for amortization of premiums and accretion of discount, provided the Advisor’s Pricing Committee has determined that the use of amortized cost is an appropriate reflection of fair value given market and issuer-specific conditions existing at the time of determination. Net asset value may change on days when investors may not sell or redeem Fund shares.

Mortgage-Related Investments will generally be valued by using a third-party pricing service. If a pricing service does not cover a particular Mortgage-Related Investment, or discontinues covering a Mortgage-Related Investment, the security will be priced using a broker quote. To derive values, pricing services and broker-dealers may use matrix pricing and valuation models, as well as recent market transactions for the same or similar assets. Occasionally, the Advisor’s pricing committee (the “ Pricing Committee ”) may determine that a pricing service price does not represent an accurate value of a Mortgage- Related Investment, based on the broker quote it receives, a recent trade in the security by the Fund, information from a portfolio manager, or other market information. In the event that the Pricing Committee determines that the pricing service price is unreliable or inaccurate based on such other information, the broker quote may be used. Additionally, if the Pricing Committee determines that the price of a Mortgage-Related Investment obtained from a pricing service and the available broker quote is unreliable or inaccurate due to market conditions or other reasons, or if a pricing service price or broker quote is unavailable, the security will be valued using fair value pricing, as described below.

Certain securities may not be able to be priced by pre-established pricing methods. Such securities may be valued by the Board or its delegate, the Advisor’s Pricing Committee, at fair value. The use of fair value pricing by the Fund is governed by valuation procedures adopted by the Board and in accordance with the provisions of the 1940 Act. These securities generally include, but are not limited to, certain restricted securities (securities which may not be publicly sold without registration under the Securities Act) for which a pricing service is unable to provide a market price; securities whose trading has been formally suspended; a security whose market or fair value price is not available from a pre-established pricing source; a security with respect to which an event has occurred that is likely to materially affect the value of the security after the market has closed but before the calculation of the Fund’s net asset value or make it difficult or impossible to obtain a reliable market quotation; and a security whose price, as provided by the pricing service, does not reflect the security’s fair value. As a general principle, the current fair value of a security would appear to be the amount which the owner might reasonably expect to receive for the security upon its current sale. When fair value prices are used generally they will differ from the current market valuations. See the Fund’s SAI for details.

Fund Service Providers

The Bank of New York Mellon, 101 Barclay Street, New York, New York 10286, acts as the administrator, custodian and fund accounting and transfer agent for the Fund. Chapman and Cutler LLP, 111 West Monroe Street, Chicago, Illinois 60603, serves as legal counsel to the Fund.

Premium/Discount Information

The table that follows presents information about the differences between the Fund’s daily market price on Nasdaq and its net asset value. The “Market Price” of the Fund generally is determined using the midpoint between the highest bid and lowest offer on Nasdaq, as of the time the Fund’s net asset value is calculated. The Fund’s Market Price may be at, above, or below its net asset value. The net asset value of the Fund will fluctuate with changes in the market value of its portfolio holdings. The Market Price of the Fund will fluctuate in accordance with changes in its net asset value, as well as market supply and demand.

Premiums or discounts are the differences (generally expressed as a percentage) between the net asset value and Market Price of the Fund on a given day, generally at the time net asset value is calculated. A premium is the amount that the Fund is trading above the reported net asset value. A discount is the amount that the Fund is trading below the reported net asset value.

The following information shows the frequency distribution of premiums and discounts of the daily bid/ask price of the Fund against the Fund’s net asset value. The information shown for the Fund is for the period indicated. Shareholders may pay more than net asset value when they buy Fund shares and receive less than net asset value when they sell those shares because shares are bought and sold at current market price. All data presented here represents past performance, which cannot be

21

used to predict future results. Information about the premiums and discounts at which the Fund’s shares have traded is available on the Fund’s website at www.ftportfolios.com.

First Trust Low Duration Opportunities ETF (LMBS)
Bid/Ask Midpoint vs. Net Asset Value

Number of Days Bid/Ask Midpoint At/Above Net Asset Value

	0.00% – 0.49%	0.50% – 0.99%	1.00% – 1.99%	>=2.00%
12 Months Ended 12/31/2017	235	0	0	0

Number of Days Bid/Ask Midpoint Below Net Asset Value

	0.00% – 0.49%	0.50% – 0.99%	1.00% – 1.99%	>=2.00%
12 Months Ended 12/31/2017	16	0	0	0

Total Return Information

The table below compares the total return of the Fund to a broad-based security market index. The information presented for the Fund is for the period indicated.

“Average annual total returns” represent the average annual change in the value of an investment over the period indicated. “Cumulative total returns” represent the total change in value of an investment over the period indicated. The net asset value per share of the Fund is the value of one share of the Fund and is computed by dividing the value of all assets of the Fund (including accrued interest and dividends), less liabilities (including accrued expenses and dividends declared but unpaid), by the total number of outstanding shares. The net asset value return is based on the net asset value per share of the Fund, and the market return is based on the market price per share of the Fund. The price used to calculate market return ( “Market Price” ) generally is determined by using the midpoint between the highest bid and the lowest offer on Nasdaq, as of the time that the Fund's net asset value is calculated. Since the shares of the Fund typically do not trade in the secondary market until several days after the Fund's inception, for the period from inception to the first day of secondary market trading in shares of the Fund, the net asset value of the Fund is used as a proxy for the secondary market trading price to calculate market returns. Market and net asset value returns assume that all distributions have been reinvested in the Fund at Market Price and net asset value, respectively. An index is a statistical composite that tracks a specified financial market or sector. Unlike the Fund, an index does not actually hold a portfolio of securities and therefore does not incur the expenses incurred by the Fund. These expenses negatively impact the performance of the Fund. Also, market returns do not include brokerage commissions that may be payable on secondary market transactions. If brokerage commissions were included, market returns would be lower. The total returns reflect the reinvestment of dividends on securities in the Indices. The returns shown in the table below do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or the redemption or sale of shares of the Fund. The investment return and principal value of shares of the Fund will vary with changes in market conditions. Shares of the Fund may be worth more or less than their original cost when they are redeemed or sold in the market. The Fund's past performance is no guarantee of future results.

First Trust Low Duration Opportunities ETF (LMBS)
Total Returns as of October 31, 2017

		Average Annual		Cumulative
	1 Year	Inception (11/4/2014)		Inception (11/4/2014)
Fund Performance
Net Asset Value	1.22%	4.09%		12.74%
Market Price	1.08%	4.12%		12.83%
Index Performance
ICE BofAML 1-5 year US Treasury & Agency Index (1)	0.07%	1.02%		3.07%

(1)	Effective October 22, 2017, the index name changed from BofA Merrill Lynch 1-5 Year US Treasury & Agency Index to ICE BofAML 1-5 Year US Treasury & Agency Index.

22

Financial Highlights

The financial highlights table is intended to help you understand the Fund's financial performance for the periods shown. Certain information reflects financial results for a single share of the Fund. The total returns represent the rate that an investor would have earned (or lost) on an investment in the Fund (assuming reinvestment of all dividends and distributions). The information for the periods indicated has been derived from financial statements audited by Deloitte & Touche LLP, whose report, along with the Fund's financial statements, is included in the Fund's Annual Report to Shareholders dated October 31, 2017 and is incorporated by reference in the Fund's SAI, which is available upon request.

(a)	Inception date is consistent with the commencement of investment operations and is the date the initial creation units were established.
(b)	Based on average shares outstanding.
(c)	Total return is calculated assuming an initial investment made at the net asset value at the beginning of the period, reinvestment of all distributions at net asset value during the period, and redemption at net asset value on the last day of the period. The returns presented do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or the redemption or sale of Fund shares. Total return is calculated for the time period presented and is not annualized for periods of less than a year.
(d)	Annualized.
(e)	Portfolio turnover is calculated for the time period presented and is not annualized for periods of less than a year and does not include securities received or delivered from processing creations or redemptions and in-kind transactions.

(f)	The portfolio turnover rate not including mortgage dollar rolls was 97%.

23

Other Information

Continuous Offering

The Fund issues, on a continuous offering basis, its shares in one or more groups of a fixed number of Fund shares (each such group of such specified number of individual Fund shares, a “Creation Unit Aggregation” ). The method by which Creation Unit Aggregations of Fund shares are created and traded may raise certain issues under applicable securities laws. Because new Creation Unit Aggregations of shares are issued and sold by the Fund on an ongoing basis, a “distribution,” as such term is used in the Securities Act, may occur at any point. Broker-dealers and other persons are cautioned that some activities on their part may, depending on the circumstances, result in their being deemed participants in a distribution in a manner which could render them statutory underwriters and subject them to the prospectus delivery requirement and liability provisions of the Securities Act.

For example, a broker-dealer firm or its client may be deemed a statutory underwriter if it takes Creation Unit Aggregations after placing an order with FTP, breaks them down into constituent shares and sells such shares directly to customers, or if it chooses to couple the creation of a supply of new shares with an active selling effort involving solicitation of secondary market demand for shares. A determination of whether one is an underwriter for purposes of the Securities Act must take into account all the facts and circumstances pertaining to the activities of the broker-dealer or its client in the particular case, and the examples mentioned above should not be considered a complete description of all the activities that could lead to a characterization as an underwriter.

Broker-dealer firms should also note that dealers who are not “underwriters” but are effecting transactions in shares, whether or not participating in the distribution of shares, are generally required to deliver a prospectus. This is because the prospectus delivery exemption in Section 4(a)(3) of the Securities Act is not available in respect of such transactions as a result of Section 24(d) of the 1940 Act. As a result, broker-dealer firms should note that dealers who are not underwriters but are participating in a distribution (as contrasted with ordinary secondary market transactions) and thus dealing with the shares that are part of an overallotment within the meaning of Section 4(a)(3)(C) of the Securities Act would be unable to take advantage of the prospectus delivery exemption provided by Section 4(a)(3) of the Securities Act. Firms that incur a prospectus delivery obligation with respect to shares are reminded that, under the Securities Act Rule 153, a prospectus delivery obligation under Section 5(b)(2) of the Securities Act owed to a broker-dealer in connection with a sale on Nasdaq is satisfied by the fact that the prospectus is available from Nasdaq upon request. The prospectus delivery mechanism provided in Rule 153 is available with respect to transactions on a national securities exchange, a trading facility or an alternative trading system.

24

      

[THIS PAGE INTENTIONALLY LEFT BLANK.]

First Trust Low Duration Opportunities ETF

For More Information

For more detailed information on the Fund, several additional sources of information are available to you. The SAI, incorporated by reference into this prospectus, contains detailed information on the Fund's policies and operation. Additional information about the Fund's investments is available in the annual and semi-annual reports to shareholders. In the Fund's annual report, you will find a discussion of the market conditions and investment strategies that significantly impacted the Fund's performance during the last fiscal year. The Fund's most recent SAI, annual and semi-annual reports and certain other information are available free of charge by calling the Fund at (800) 621-1675, on the Fund's website at www.ftportfolios.com or through your financial advisor. Shareholders may call the toll-free number above with any inquiries.

You may obtain this and other information regarding the Fund, including the SAI and the Codes of Ethics adopted by First Trust, FTP and the Trust, directly from the Securities and Exchange Commission (the “SEC” ). Information on the SEC’s website is free of charge. Visit the SEC’s online EDGAR database at www.sec.gov or in person at the SEC’s Public Reference Room in Washington, D.C., or call the SEC at (202) 551-8090 for information on the Public Reference Room. You may also request information regarding the Fund by sending a request (along with a duplication fee) to the SEC’s Public Reference Section, 100 F Street, N.E., Washington, D.C. 20549-1520 or by sending an electronic request to publicinfo@sec.gov.

First Trust Advisors L.P.
120 East Liberty Drive, Suite 400
Wheaton, Illinois 60187
(800) 621-1675
www.ftportfolios.com

SEC File #: 333-174332

811-22559

Prospectus

First Trust North American Energy Infrastructure Fund

Ticker Symbol:	EMLP
Exchange:	NYSE Arca

First Trust North American Energy Infrastructure Fund (the “Fund” ) lists and principally trades its shares on NYSE Arca, Inc. ( “NYSE Arca” or the “Exchange” ). Market prices may differ to some degree from the net asset value of the shares. Unlike mutual funds, the Fund issues and redeems shares at net asset value, only in large specified blocks each consisting of 50,000 shares (each such block of shares called a “Creation Unit,” and collectively, the “Creation Units” ). The Fund’s Creation Units are generally issued and redeemed in-kind for securities in which the Fund invests and, in certain circumstances, for cash, and only to and from broker-dealers and large institutional investors that have entered into participation agreements.

The Fund is a series of First Trust Exchange-Traded Fund IV (the “Trust” ) and an actively managed exchange-traded fund organized as a separate series of a registered management investment company.

Except when aggregated in Creation Units, the shares are not redeemable securities of the Fund.

The Securities and Exchange Commission has not approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

Table of Contents

Summary Information	3
Additional Information on the Fund's Investment Objectives and Strategies	10
Fund Investments	10
Additional Risks of Investing in the Fund	13
Fund Organization	17
Management of the Fund	17
How to Buy and Sell Shares	18
Dividends, Distributions and Taxes	19
Federal Tax Matters	19
Distribution Plan	21
Net Asset Value	22
Fund Service Providers	23
Premium/Discount Information	23
Total Return Information	23
Financial Highlights	25
Other Information	26

Investment Objectives

The First Trust Senior Loan Fund's (the " Fund ") primary investment objective is to provide high current income. The Fund’s secondary investment objective is the preservation of capital.

Fees and Expenses of the Fund

The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund. Investors purchasing and selling shares may be subject to costs (including customary brokerage commissions) charged by their broker, which are not reflected in the table below.

Shareholder Fees
(fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

None

    

(1)	Although the Fund has adopted a 12b-1 plan that permits it to pay up to 0.25% per annum, it will not pay 12b-1 fees at any time before March 31, 2019.

Example

The example below is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. This example does not take into account customary brokerage commissions that you pay when purchasing or selling shares of the Fund in the secondary market.

The example assumes that you invest $10,000 in the Fund for the time periods indicated. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain at current levels until March 31, 2019, and thereafter at 1.13% to represent the imposition of the 12b-1 fee of 0.25% per annum of the Fund’s average daily net assets. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

1 Year	3 Years	5 Years	10 Years
$90	$334	$598	$1,352

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 110% of the average value of its portfolio.

Principal Investment Strategies

Under normal market conditions, the Fund seeks to outperform each of the Primary Index and Secondary Index (as defined below) by investing at least 80% of its net assets (including investment borrowings) in first lien senior floating rate bank loans ( “Senior Loans” ). The S&P/LSTA U.S. Leveraged Loan 100 Index (the “Primary Index” ) is a market value-weighted index designed to measure the performance of the largest segment of the U.S. syndicated leveraged loan market. The Primary Index consists of 100 loan facilities drawn from a larger benchmark, the S&P/LSTA Leveraged Loan Index. The Markit iBoxx USD Leveraged Loan Index (the “Secondary Index” ) selects the 100 most liquid Senior Loans in the market. The Fund does not seek to track either the Primary or Secondary Index, but rather seeks to outperform each of the indices. It is anticipated that the Fund, in

3

accordance with its principal investment strategy, will invest approximately 50% to 75% of its net assets in Senior Loans that are eligible for inclusion in and meet the liquidity thresholds of the Primary and/or the Secondary Indices at the time of investment.

A Senior Loan is an advance or commitment of funds made by one or more banks or similar financial institutions to one or more corporations, partnerships or other business entities and typically pays interest at a floating or adjusting rate that is determined periodically at a designated premium above a base lending rate, most commonly the London Interbank Offered Rate ( “LIBOR” ). A Senior Loan is considered senior to all other unsecured claims against the borrower, senior to or pari passu with all other secured claims, meaning that in the event of a bankruptcy the Senior Loan, together with other first lien claims, is entitled to be the first to be repaid out of proceeds of the assets securing the loans, before other existing unsecured claims or interests receive repayment. However, in bankruptcy proceedings, there may be other claims, such as taxes or additional advances that take precedence.

The Fund invests in Senior Loans made predominantly to businesses operating in North America, but may also invest in Senior Loans made to businesses operating outside of North America. The Fund may invest in Senior Loans directly, either from the borrower as part of a primary issuance or in the secondary market through assignments of portions of Senior Loans from third parties, or participations in Senior Loans, which are contractual relationships with an existing lender in a loan facility whereby the Fund purchases the right to receive principal and interest payments on a loan but the existing lender remains the record holder of the loan. The Senior Loans included in the Fund’s portfolio often maintain an average interest rate duration of less than 90 days; however, the inclusion of LIBOR floors on certain Senior Loans or other factors may cause interest rate duration to be longer than 90 days.

When identifying prospective investment opportunities in Senior Loans, First Trust Advisors L.P., the Fund’s investment advisor, currently intends to invest primarily in Senior Loans that are below investment grade quality at the time of investment, and relies on fundamental credit analysis in an effort to attempt to minimize the loss of the Fund’s capital and to select assets that provide attractive relative value. Securities rated below investment grade, commonly referred to as “junk” or “high yield” securities, include securities that are rated Ba1/BB+/BB+ or below by Moody’s Investors Service, Inc. ( “Moody’s” ), Fitch Inc., or Standard & Poor’s, Inc. ( “S&P” ), respectively. The Fund may also invest in unrated securities deemed by the investment advisor to be of comparable quality to those securities rated below investment grade. The investment advisor does not intend to purchase Senior Loans that are in default; however, the Fund may hold a Senior Loan that has defaulted subsequent to its purchase by the Fund.

The Fund may also invest up to 20% of its net assets in (1) non-Senior Loan debt securities, which may be fixed-rate or floating-rate income-producing securities (including, without limitation, U.S. government debt securities and corporate debt securities, which may include convertible bonds), (2) warrants and equity securities issued by a borrower or its affiliates, and/or (3) securities of other investment companies.

The Fund’s investment advisor combines a fundamental credit selection process with relative value analysis and top-down macroeconomic perspectives when selecting investment opportunities. The Fund’s investment advisor believes that an evolving investment environment offers varying degrees of investment risk opportunities in the bank loan, high yield and other fixed income instrument markets. To capitalize on attractive investments and effectively manage potential risk, the Fund’s investment advisor believes that the combination of thorough and continuous credit analysis, market evaluation, diversification and the ability to reallocate investments is critical to achieving higher risk-adjusted returns.

Principal Risks

You could lose money by investing in the Fund. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. There can be no assurance that the Fund’s investment objectives will be achieved.

AUTHORIZED PARTICIPANT CONCENTRATION RISK. Only an authorized participant (as defined in the “Frequent Purchases and Redemptions” Section) may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of institutions that act as authorized participants. To the extent that these institutions exit the business or are unable to proceed with creation and/or redemption orders with respect to the Fund and no other authorized participant is able to step forward to create or redeem, in either of these cases, Fund shares may trade at a discount to the Fund’s net asset value and possibly face delisting.

BANK LOANS RISK. An investment in bank loans subjects the Fund to credit risk, which is heightened for bank loans in which the Fund invests because companies that issue such loans tend to be highly leveraged and thus are more susceptible to the

4

risks of interest deferral, default and/or bankruptcy. Senior Loans, in which the Fund may invest, are usually rated below investment grade but may also be unrated. As a result, the risks associated with these Senior Loans are similar to the risks of high yield fixed income instruments. An economic downturn would generally lead to a higher non-payment rate, and a Senior Loan may lose significant market value before a default occurs. Moreover, any specific collateral used to secure a Senior Loan may decline in value or become illiquid, which would adversely affect the Senior Loan's value. Unlike the securities markets, there is no central clearinghouse for loan trades, and the loan market has not established enforceable settlement standards or remedies for failure to settle. Therefore, portfolio transactions in Senior Loan may have uncertain settlement time periods. Senior Loans are subject to a number of risks described elsewhere in this prospectus, including liquidity risk and the risk of investing in below investment grade fixed income instruments.

CALL RISK. If an issuer calls higher-yielding securities held by the Fund, performance could be adversely impacted. During periods of falling interest rates, issuers of callable securities may call (redeem) securities with higher coupon rates or interest rates before their maturity dates. The Fund would then lose any price appreciation above the bond’s call price and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund’s income. Such redemptions and subsequent reinvestments would also increase the Fund’s portfolio turnover rate.

CASH TRANSACTIONS RISK. The Fund will, under most circumstances, effect a significant portion of creations and redemptions for cash, rather than in-kind securities. As a result, an investment in the Fund may be less tax-efficient than an investment in an exchange-traded fund that effects its creations and redemptions for in-kind securities. Because the Fund may effect a portion of redemptions for cash, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. A sale of shares may result in capital gains or losses and may also result in higher brokerage costs.

CONVERTIBLE BONDS RISK. The market values of convertible bonds tend to decline as interest rates increase and, conversely, to increase as interest rates decline. A convertible bond’s market value also tends to reflect the market price of the common stock of the issuing company.

CREDIT RISK. Credit risk is the risk that an issuer of a security will be unable or unwilling to make dividend, interest and/or principal payments when due and the related risk that the value of a security may decline because of concerns about the issuer’s ability to make such payments. Credit risk may be heightened for the Fund because it invests a substantial portion of its net assets in high yield or "junk" debt. Such securities, while generally offering higher yields than investment grade debt with similar maturities, involve greater risks, including the possibility of dividend or interest deferral, default or bankruptcy, and are regarded as predominantly speculative with respect to the issuer's capacity to pay dividends or interest and repay principal. Credit risk is heightened for loans in which the Fund invests because companies that issue such loans tend to be highly leveraged and thus are more susceptible to the risks of interest deferral, default and/or bankruptcy.

CURRENCY RISK . The Fund may hold investments that are denominated in non-U.S. currencies, or in securities that provide exposure to such currencies, currency exchange rates or interest rates denominated in such currencies. Changes in currency exchange rates and the relative value of non-U.S. currencies will affect the value of the Fund’s investments and the value of your Fund shares. Currency exchange rates can be very volatile and can change quickly and unpredictably. As a result, the value of an investment in the Fund may change quickly and without warning and you may lose money. You may lose money if the local currency of a foreign market depreciates against the U.S. dollar, even if the local currency value of the Fund’s holdings goes up. The Fund intends to hedge certain of its non-U.S. dollar holdings.

CYBER SECURITY RISK. As the use of Internet technology has become more prevalent in the course of business, the Fund has become more susceptible to potential operational risks through breaches in cyber security. A breach in cyber security refers to both intentional and unintentional events that may cause the Fund to lose proprietary information, suffer data corruption or lose operational capacity. Such events could cause the Fund to incur regulatory penalties, reputational damage, additional compliance costs associated with corrective measures and/or financial loss. Cyber security breaches may involve unauthorized access to the Fund’s digital information systems through “hacking” or malicious software coding, but may also result from outside attacks such as denial-of-service attacks through efforts to make network services unavailable to intended users. In addition, cyber security breaches of the Fund’s third party service providers, such as its administrator, transfer agent, custodian or sub-advisor, as applicable, or issuers in which the Fund invests, can also subject the Fund to many of the same risks associated with direct cyber security breaches. The Fund has established risk management systems designed to reduce the risks associated with cyber security. However, there is no guarantee that such efforts will succeed, especially because the Fund does not directly control the cyber security systems of issuers or third party service providers.

EXTENSION RISK. Extension risk is the risk that, when interest rates rise, certain obligations will be paid off by the issuer (or obligor) more slowly than anticipated, causing the value of these securities to fall. Rising interest rates tend to extend the

5

duration of securities, making them more sensitive to changes in interest rates. The value of longer-term securities generally changes more in response to changes in interest rates than shorter-term securities. As a result, in a period of rising interest rates, securities may exhibit additional volatility and may lose value.

FLUCTUATION OF NET ASSET VALUE RISK . The net asset value of shares of the Fund will generally fluctuate with changes in the market value of the Fund’s holdings. The market prices of shares will generally fluctuate in accordance with changes in net asset value as well as the relative supply of and demand for shares on the Exchange. The Fund’s investment advisor cannot predict whether shares will trade below, at or above their net asset value because the shares trade on the Exchange at market prices and not at net asset value. Price differences may be due, in large part, to the fact that supply and demand forces at work in the secondary trading market for shares will be closely related to, but not identical to, the same forces influencing the prices of the holdings of the Fund trading individually or in the aggregate at any point in time. However, given that shares can only be purchased and redeemed either in-kind or for cash in Creation Units, and only to and from broker-dealers and large institutional investors that have entered into participation agreements (unlike shares of closed-end funds, which frequently trade at appreciable discounts from, and sometimes at premiums to, their net asset value), the Fund’s investment advisor believes that large discounts or premiums to the net asset value of shares should not be sustained.

HIGH YIELD SECURITIES RISK. High yield securities, or “junk” bonds, are subject to greater market fluctuations and risk of loss than securities with higher ratings, and therefore, are considered to be highly speculative. These securities are issued by companies that may have limited operating history, narrowly focused operations and/or other impediments to the timely payment of periodic interest and principal at maturity. If the economy slows down or dips into recession, the issuers of high yield securities may not have sufficient resources to continue making timely payment of periodic interest and principal at maturity. The market for high yield securities is generally smaller and less liquid than that for investment grade securities. High yield securities are generally not listed on a national securities exchange but trade in the over-the-counter markets. Due to the smaller, less liquid market for high yield securities, the bid-offer spread on such securities is generally greater than it is for investment grade securities and the purchase or sale of such securities may take longer to complete. In general, high yield securities may have a greater risk of default than other types of securities.

ILLIQUID SECURITIES RISK. Illiquid securities involve the risk that the securities will not be able to be sold at the time desired by the Fund or at prices approximately the value at which the Fund values the securities.

INCOME RISK. If interest rates fall, the income from the Fund’s portfolio will likely decline if the Fund holds floating rate debt that will adjust lower with falling interest rates. For loans, interest rates typically reset periodically.

INTEREST RATE RISK. Interest rate risk is the risk that the value of the debt securities in the Fund’s portfolio will decline because of rising market interest rates. Interest rate risk is generally lower for shorter term debt securities and higher for longer term debt securities. Duration is a measure of the expected price volatility of a debt instrument as a result of changes in market rates of interest, based on, among other factors, the weighted average timing of the instrument’s expected principal and interest payments. In general, duration represents the expected percentage change in the value of a security for an immediate 1% change in interest rates. Therefore, prices of debt securities with shorter durations tend to be less sensitive to interest rate changes than debt securities with longer durations. As the value of a debt security changes over time, so will its duration.

LIQUIDITY RISK. The Fund invests a substantial portion of its assets in lower-quality debt issued by companies that are highly leveraged. Lower-quality debt tends to be less liquid than higher-quality debt. Moreover, smaller debt issues tend to be less liquid than larger debt issues. If the economy experiences a sudden downturn, or if the debt markets for such companies become distressed, the Fund may have particular difficulty selling its assets in sufficient amounts, at reasonable prices and in a sufficiently timely manner to raise the cash necessary to meet any potentially heavy redemption requests by Fund shareholders.

MANAGEMENT RISK. The Fund is subject to management risk because it is an actively managed portfolio. In managing the Fund’s investment portfolio, the Fund’s investment advisor will apply investment techniques and risk analyses that may not have the desired result. There can be no guarantee that the Fund will meet its investment objectives.

MARKET MAKER RISK. If the Fund has lower average daily trading volumes, it may rely on a small number of third-party market makers to provide a market for the purchase and sale of shares. Any trading halt or other problem relating to the trading activity of these market makers could result in a dramatic change in the spread between the Fund’s net asset value and the price at which the Fund’s shares are trading on the Exchange which could result in a decrease in value of the Fund’s shares. In addition, decisions by market makers or authorized participants to reduce their role or step away from these activities in times of market stress could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the

6

underlying values of the Fund’s portfolio securities and the Fund’s market price. This reduced effectiveness could result in Fund shares trading at a discount to net asset value and also in greater than normal intraday bid-ask spreads for Fund shares.

MARKET RISK. Market risk is the risk that a particular security owned by the Fund or shares of the Fund in general may fall in value. Securities are subject to market fluctuations caused by such factors as economic, political, regulatory or market developments, changes in interest rates and perceived trends in securities prices. Shares of the Fund could decline in value or underperform other investments.

NON-U.S. SECURITIES RISK. Non-U.S. securities are subject to higher volatility than securities of domestic issuers due to possible adverse political, social or economic developments, restrictions on foreign investment or exchange of securities, lack of liquidity, currency exchange rates, excessive taxation, government seizure of assets, different legal or accounting standards, and less government supervision and regulation of exchanges in foreign countries.

OTHER DEBT SECURITIES RISK. Secured loans that are not first lien loans, unsecured loans and other debt securities are subject to many of the same risks that affect Senior Loans; however they are often unsecured and/or lower in the issuer’s capital structure than Senior Loans, and thus may be exposed to greater risk of default and lower recoveries in the event of a default. This risk can be further heightened in the case of below investment grade instruments. Additionally, most fixed income securities are fixed-rate and thus are generally more susceptible than floating rate loans to price volatility related to changes in prevailing interest rates.

PORTFOLIO TURNOVER RISK. The Fund’s strategy may frequently involve buying and selling portfolio securities to rebalance the Fund’s exposure to various market sectors. portfolio turnover may result in the Fund paying higher levels of transaction costs and generating greater tax liabilities for shareholders. Portfolio turnover risk may cause the Fund’s performance to be less than you expect.

PREPAYMENT RISK. Loans are subject to prepayment risk. The degree to which borrowers prepay loans, whether as a contractual requirement or at their election, may be affected by general business conditions, the financial condition of the borrower and competitive conditions among loan investors, among others. As such, prepayments cannot be predicted with accuracy. Upon a prepayment, either in part or in full, the actual outstanding debt on which the Fund derives interest income will be reduced. The Fund may not be able to reinvest the proceeds received on terms as favorable as the prepaid loan.

TRADING ISSUES RISK . Although the shares of the Fund are listed for trading on the Exchange, there can be no assurance that an active trading market for such shares will develop or be maintained. Trading in shares on the Exchange may be halted due to market conditions or for reasons that, in the view of the Exchange, make trading in shares inadvisable. In addition, trading in shares on the Exchange is subject to trading halts caused by extraordinary market volatility pursuant to the Exchange’s “circuit breaker” rules. Market makers are under no obligation to make a market in the Fund’s shares, and authorized participants are not obligated to submit purchase or redemption orders for Creation Units. There can be no assurance that the requirements of the Exchange necessary to maintain the listing of the Fund will continue to be met or will remain unchanged. In particular, if the Fund does not comply with any provision of the listing standards of the Exchange that are applicable to the Fund, and cannot bring itself into compliance within a reasonable period after discovering the matter, the Exchange may remove the shares of the Fund from listing. The Fund may have difficulty maintaining its listing on the Exchange in the event the Fund’s assets are small or the Fund does not have enough shareholders.

Annual Total Return

The bar chart and table below illustrate the annual calendar year returns of the Fund based on net asset value as well as the average annual Fund returns. The bar chart and table provide an indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year-to-year and by showing how the Fund’s average annual total returns based on net asset value compared to those of two specialty market indices. See “Total Return Information” for additional performance information regarding the Fund. The Fund’s performance information is accessible on the Fund’s website at www.ftportfolios.com.

Returns before taxes do not reflect the effects of any income or capital gains taxes. All after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of any state or local tax. Returns after taxes on distributions reflect the taxed return on the payment of dividends and capital gains. Returns after taxes on distributions and sale of shares assume you sold your shares at period end, and, therefore, are also adjusted for any capital gains or losses incurred. Returns for the market indices do not include expenses, which are deducted from Fund returns, or taxes.

7

Your own actual after-tax returns will depend on your specific tax situation and may differ from what is shown here. After-tax returns are not relevant to investors who hold Fund shares in tax-deferred accounts such as individual retirement accounts ( IRAs ) or employee-sponsored retirement plans.

First Trust Senior Loan Fund
Calendar Year Total Returns as of 12/31

During the periods shown in the chart above:

Best Quarter		Worst Quarter
2.17%	March 31, 2016	-1.63%	December 31, 2015

The Fund’s past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

Average Annual Total Returns for the Periods Ended December 31, 2017

The following persons serve as portfolio managers of the Fund.

•	William Housey, CFA, Senior Vice President and Senior Portfolio Manager of First Trust
•	Scott D. Fries, CFA, Senior Vice President and Portfolio Manager of First Trust

The portfolio managers are primarily and jointly responsible for the day-to-day management of the Fund. Each portfolio manager has served as a part of the portfolio management team of the Fund since 2013.

8

Purchase and Sale of Fund Shares

The Fund issues and redeems shares on a continuous basis, at net asset value, only in Creation Units consisting of 50,000 shares. The Fund’s Creation Units are generally issued and redeemed for cash, and in certain circumstances, in-kind for securities in which the Fund invests, and only to and from broker-dealers and large institutional investors that have entered into participation agreements. Individual shares of the Fund may only be purchased and sold on Nasdaq and other eligible securities exchanges through a broker-dealer. Shares of the Fund trade on Nasdaq at market prices rather than net asset value, which may cause the shares to trade at a price greater than net asset value (premium) or less than net asset value (discount).

Tax Information

The Fund’s distributions are taxable and will generally be taxed as ordinary income or capital gains. Distributions on shares held in a tax-deferred account, while not immediately taxable, will be subject to tax when the shares are no longer held in a tax-deferred account.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase shares of the Fund through a broker-dealer or other financial intermediary (such as a bank), First Trust and First Trust Portfolios L.P., the Fund’s distributor, may pay the intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.

9

Additional Information on the Fund's Investment Objectives and Strategies

The Fund's investment objectives are fundamental and may not be changed without approval by the holders of a majority of the outstanding voting securities of the Fund. Unless an investment policy is identified as being fundamental, all investment policies included in this prospectus and the Fund’s Statement of Additional Information ( “SAI” ) are non-fundamental and may be changed by the Board of Trustees (the “Board” ) of the First Trust Exchange-Traded Fund IV (the “Trust” ), of which the Fund is a series, without shareholder approval. If there is a material change to the Fund's principal investment strategies, you should consider whether the Fund remains an appropriate investment for you. There is no guarantee that the Fund will achieve its investment objectives.

The Fund has adopted a non-fundamental investment policy pursuant to Rule 35d-1 under the Investment Company Act of 1940, as amended (the “ 1940 Act ”) (the “Name Policy” ), whereby the Fund, under normal market conditions, invests at least 80% of its net assets (including investment borrowings) in Senior Loans. The Name Policy may be changed by the Board of Trustees without shareholder approval upon 60 days’ prior written notice. If there is a material change to the Fund’s principal investment strategies, you should consider whether the Fund remains an appropriate investment for you. There is no guarantee that the Fund will achieve its investment objectives.

When identifying prospective investment opportunities in Senior Loans, the Advisor intends to invest primarily in Senior Loans that are below investment grade quality at the time of investment, and will rely on fundamental credit analysis in an effort to attempt to minimize the loss of the Fund’s capital. The Advisor seeks to invest in Senior Loans or other debt of companies possessing some or all of the attributes described below, which it believes will help generate higher risk-adjusted total returns:

•	Senior Loans or other debt of companies that have developed strong positions within their respective markets and exhibit the potential to maintain sufficient cash flows and profitability to service their obligations in a range of economic environments.
•	Senior Loans or other debt of companies that possess advantages in scale, scope, customer loyalty, product pricing or product quality versus their competitors, thereby minimizing business risk and protecting profitability.
•	Senior Loans or other debt of established companies that have demonstrated a record of profitability and cash flows over several economic cycles.
•	Senior Loans or other debt of a target company that has an experienced management team with an established track record of success.

The Advisor seeks to invest in a portfolio of Senior Loans or other debt among various borrowers and industries, thereby potentially reducing the risk of a downturn in any one company or industry having a disproportionate impact on the value of the Fund’s holdings. Loans, and the collateral securing them, are typically monitored by agents for the lenders, which may be the originating bank or banks.

Fund Investments

Principal Investments

Senior Loans

Senior Loans represent debt obligations of sub-investment grade corporate borrowers, similar to high yield bonds; however, Senior Loans are different from traditional high yield bonds in that Senior Loans are typically senior to other obligations of the borrower and secured by the assets of the borrower. Senior Loans rank at the top of a borrower’s capital structure in terms of priority of payment, ahead of any subordinated debt (high yield) or the borrower’s common equity. These loans are also secured, as the holders of these loans have a lien on most if not all of the corporate borrower’s plant, property, equipment, receivables, cash balances, licenses, trademarks, etc. Furthermore, the corporate borrower of Senior Loans executes a credit agreement that typically restricts what it can do (debt incurrence, asset dispositions, etc.) without the lenders’ approval, and, in addition, may require the borrower to meet certain ongoing financial covenants. Finally, Senior Loans typically pay interest at rates which are determined periodically on the basis of a floating base lending rate, primarily the LIBOR, plus a premium. Senior Loans are typically made to U.S. and, to a lesser extent, non-U.S. corporations, partnerships and other business entities which operate in various industries and geographical regions. Borrowers may obtain these loans to, among other reasons, refinance existing debt and for acquisitions, dividends, leveraged buyouts, and general corporate purposes. Senior floating rate loans are primarily made to companies whose debt is rated below investment grade. Senior floating rate loans typically hold or share a first lien priority and pay interest at rates which are determined periodically on the basis of a floating base

10

lending rate, primarily the LIBOR, plus a premium. Senior floating rate loans are typically made to U.S. and, to a lesser extent, non-U.S. corporations, partnerships and other business entities which operate in various industries and geographical regions. Borrowers may obtain these loans to, among other reasons, refinance existing debt and for acquisitions, dividends, leveraged buyouts, and general corporate purposes.

Corporate Debt Securities

The Fund may invest in corporate debt securities issued by U.S. and non-U.S. companies of all kinds, including those with small, mid and large capitalizations. Corporate debt securities are fixed income securities issued by businesses to finance their operations. Notes, bonds, debentures and commercial paper are the most common types of corporate debt securities, with the primary differences being their maturities and secured or unsecured status. Commercial paper has the shortest term and is usually unsecured. Corporate debt may be rated investment grade or below investment grade and may carry fixed or floating rates of interest.

Other Debt Securities

The Fund may invest in unsecured and/or subordinated bank loans, loan participations and unfunded contracts. The Fund may invest in such loans by purchasing assignments on all or a portion of loans or loan participations from third parties. These loans are made by or issued to corporations primarily to finance acquisitions, refinance existing debt, support organic growth, or pay out dividends, and are typically originated by large banks and then syndicated out to institutional investors as well as to other banks. Bank loans typically bear interest at a floating rate although some loans pay a fixed rate.

High Yield Debt

The Fund invests primarily in debt instruments ( e.g. , bonds, loans and convertible bonds) that are rated below investment grade, or unrated securities deemed by the Advisor to be of comparable quality. Debt securities rated below investment grade are commonly referred to as “ high yield ” or “ junk ” debt. For purposes of determining whether a security is below investment grade, the lowest available rating will be considered. High yield debt may be issued by companies without long track records of sales and earnings, or by issuers that have questionable credit strength. High yield debt and comparable unrated debt securities: (a) will likely have some quality and protective characteristics that, in the judgment of the rating agency evaluating the instrument, are out weighed by large uncertainties or major risk exposures to adverse conditions; and (b) are predominantly speculative with respect to the issuer’s capacity to pay dividends or interest and repay principal in accordance with the terms of the obligation.

Non-U.S. Investments

The Fund may invest in securities issued by non-U.S. companies that are traded over-the-counter or listed on an exchange. Non-U.S. debt securities in which the Fund may invest include debt securities issued or guaranteed by companies organized under the laws of countries other than the United States, debt securities issued or guaranteed by foreign, national, provincial, state, municipal or other governments with taxing authority or by their agencies or instrumentalities and debt obligations of supranational governmental entities such as the World Bank or European Union. These debt securities may be U.S. dollar-denominated or non-U.S. dollar-denominated. Non-U.S. debt securities also include U.S. dollar-denominated debt obligations, such as “Yankee Dollar” obligations, of foreign issuers and of supranational government entities. Yankee Dollar obligations are U.S. dollar-denominated obligations issued in the U.S. capital markets by foreign corporations, banks and governments. Foreign debt securities also may be traded on foreign securities exchanges or in over-the-counter capital markets. Under normal market conditions, up to 10% of the net assets (including investment borrowings) of the Fund may be denominated in currencies other than the U.S. dollar. To the extent the Fund invests in such instruments, the value of the assets of the Fund as measured in U.S. dollars will be affected by changes in exchange rates. Generally, the Fund’s currency exchange transactions will be conducted on a spot ( i.e. , cash) basis at the spot rate prevailing in the currency exchange market. The cost of the Fund’s currency exchange transactions will generally be the difference between the bid and offer spot rate of the currency being purchased or sold. In order to protect against uncertainty in the level of future currency exchange rates, the Fund is authorized to enter into various currency exchange transactions.

Non-Principal Investments

U.S. Government Securities

The Fund may invest in U.S. government securities. U.S. government securities include U.S. Treasury obligations and securities issued or guaranteed by various agencies of the U.S. government, or by various instrumentalities that have been established or sponsored by the U.S. government. U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. government.

11

Securities issued or guaranteed by federal agencies and U.S. government sponsored instrumentalities may or may not be backed by the full faith and credit of the U.S. government.

Preferred Securities

The Fund may invest in preferred securities, which generally pay fixed or adjustable-rate dividends or interest to investors and have preference over common stock in the payment of dividends or interest and the liquidation of a company’s assets, which means that a company typically must pay dividends or interest on its preferred securities before paying any dividends on its common stock. Preferred securities are generally junior to all forms of the company’s debt, including both senior and subordinated debt.

Cash Equivalents and Short-Term Investments

Normally, the Fund invests substantially all of its assets to meet its investment objectives. However, the Fund may invest in short-term debt securities, money market funds and other cash equivalents, or it may hold cash. The percentage of the Fund invested in such holdings varies and depends on several factors, including market conditions. For temporary defensive purposes and during periods of high cash inflows or outflows, the Fund may depart from its principal investment strategies and invest part or all of its assets in these securities, or it may hold cash. During such periods, the Fund may not be able to achieve its investment objectives. The Fund may adopt a defensive strategy when the portfolio managers believe securities in which the Fund normally invests have elevated risks due to political or economic factors and in other extraordinary circumstances. For more information on eligible short-term investments, see the SAI.

Illiquid Securities

The Fund may invest up to 15% of its net assets in securities and other instruments that are, at the time of investment, illiquid (determined using the Securities and Exchange Commission's standard applicable to investment companies, i.e. , securities that cannot be disposed of by the Fund within seven days in the ordinary course of business at approximately the amount at which the Fund has valued the securities). For this purpose, illiquid securities may include, but are not limited to certain restricted securities (securities the disposition of which is restricted under the federal securities laws), certain securities that may only be resold pursuant to Rule 144A under the Securities Act of 1933, as amended (the “Securities Act” ), that are deemed to be illiquid, and certain repurchase agreements.

Investment Companies and Other Pooled Investment Vehicles

The Fund may invest in securities of investment companies, including exchange-traded funds ( “ETFs” ). In addition, the Fund may invest a portion of its assets in pooled investment vehicles (other than investment companies) that invest primarily in securities of the types in which the Fund may invest directly. The Fund's ability to invest in other investment companies is limited by the 1940 Act and the related rules and interpretations. The Fund has adopted a policy that it will not invest in other investment companies in excess of 1940 Act limits in reliance on Sections 12(d)(1)(F) and 12(d)(1)(G) of the 1940 Act. ETFs trade on a securities exchange and their shares may, at times, trade at a premium or discount to their net asset value.

As a shareholder in a pooled investment vehicle, the Fund bears its ratable share of that vehicle's expenses, and would remain subject to payment of the fund's advisory and administrative fees with respect to assets so invested. Shareholders would therefore be subject to duplicative expenses to the extent the Fund invests in other pooled investment vehicles. In addition, the Fund will incur brokerage costs when purchasing and selling shares of ETFs and closed-end investment companies. Securities of other pooled investment vehicles may be leveraged, in which case the value and/or yield of such securities will tend to be more volatile than securities of unleveraged vehicles.

The Fund’s investment in other investment companies that adhere to a Name Policy with respect to senior loans shall be counted towards the Fund’s investment policy of investing, under normal market conditions, at least 80% of its net assets (including investment borrowings) in Senior Loans. For purposes of satisfying the Fund’s investment restrictions, such senior loan funds will also be considered below investment grade securities. The Fund may also invest in certain affiliated open-end funds or ETFs that are advised by the Advisor, in which case the Fund shall receive a rebate for any advisory fees borne in connection with the purchase of the shares of such affiliated open-end funds or ETFs.

Disclosure of Portfolio Holdings

A description of the policies and procedures with respect to the disclosure of the Fund's portfolio securities is included in the Fund's SAI, which is available on the Fund's website at www.ftportfolios.com.

12

Additional Risks of Investing in the Fund

Risk is inherent in all investing. Investing in the Fund involves risk, including the risk that you may lose all or part of your investment. There can be no assurance that the Fund will meet its stated objectives. Before you invest, you should consider the following supplemental disclosure pertaining to the Principal Risks set forth above as well as additional Non-Principal Risks set forth below in this prospectus.

Principal Risks

BANK LOANS RISK. The bank loans in which the Fund may invest may not (i) be rated at the time of investment, (ii) be registered with the Securities and Exchange Commission, (iii) be listed on a securities exchange or (iv) have sufficient collateral securing the loan or the collateral may not be available in the event of bankruptcy. In addition, the amount of public information available with respect to such bank loans may be less extensive than that available for more widely rated, registered and exchange-listed securities. Because no active trading market may exist for some of the bank loans in which the Fund may invest, such bank loans may be illiquid and more difficult to value than more liquid instruments for which a trading market does exist. Unlike the securities markets, there is no central clearinghouse for bank loan trades, and the bank loan market has not established enforceable settlement standards or remedies for failure to settle. Therefore, portfolio transactions in bank loans may have uncertain settlement time periods. Because the interest rates of floating rate loans in which the Fund may invest may reset frequently, if market interest rates fall, the loans’ interest rates will be reset to lower levels, potentially reducing the Fund’s income.

First Trust or its affiliates may participate in the primary and secondary market for bank loans. Because of limitations imposed by applicable law, the presence of such affiliates in the bank loan market may restrict the Fund’s ability to acquire some loans or affect the timing or price of loan acquisitions. Also, because First Trust may wish to invest in the publicly traded securities of an obligor, the Fund may not have access to material non-public information regarding the obligor to which other investors have access.

CASH TRANSACTIONS RISK. The Fund intends to effect a significant portion of creations and redemptions for cash, rather than in-kind securities. As a result, an investment in the Fund may be less tax-efficient than an investment in an ETF that effects its creations and redemptions for in-kind securities. ETFs are able to make in-kind redemptions and avoid being taxed on gains on the distributed portfolio securities at the fund level. Because the Fund intends to effect a significant portion of redemptions for cash, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. Any recognized gain on these sales by the Fund will generally cause the Fund to recognize a gain it might not otherwise have recognized, or to recognize such gain sooner than would otherwise be required if it were to distribute portfolio securities in-kind. The Fund intends to distribute these gains to shareholders to avoid being taxed on this gain at the fund level and otherwise comply with the special tax rules that apply to it. This strategy may cause shareholders to be subject to tax on gains they would not otherwise be subject to, or at an earlier date than if they had made an investment in a different ETF. Moreover, cash transactions may have to be carried out over several days if the securities market is relatively illiquid, and such transactions may involve considerable brokerage fees and taxes. These brokerage fees and taxes, which will be higher than if the Fund sold and redeemed its shares principally in-kind, will be passed on to those purchasing and redeeming Creation Units in the form of creation and redemption transaction fees. In addition, these factors may result in wider spreads between the bid and the offered prices of the Fund's shares than for ETFs that distribute portfolio securities in-kind.

CREDIT RISK. An issuer of a debt instrument may be unable or unwilling to make dividend, interest and/or principal payments when due and the related risk that the value of an instrument may decline because of concerns about the issuer’s ability or unwillingness to make such payments. High yield and comparable unrated debt securities, while generally offering higher yields than investment grade debt with similar maturities, involve greater risks, including the possibility of dividend or interest deferral, default or bankruptcy, and are regarded as predominantly speculative with respect to the issuer’s capacity to pay dividends or interest and repay principal. Credit risk is heightened for loans in which the Fund invests because companies that issue such loans tend to be highly leveraged and thus are more susceptible to the risks of interest deferral, default and/or bankruptcy.

CURRENCY RISK. An investment in non-U.S. securities involves further risk due to currency exchange rates. Changes in currency exchange rates may affect the Fund's net asset value, the value of dividends and interest earned, and gains and losses realized on the sale of securities. An increase in the strength of the U.S. dollar relative to other currencies may cause the value of the Fund to decline. Certain non-U.S. currencies may be particularly volatile, and non-U.S. governments may intervene in the currency markets, causing a decline in value or liquidity in the Fund's non-U.S. holdings whose value is tied to the affected non-U.S. currency.

13

DISTRESSED SECURITIES RISK. The Fund may invest in distressed securities, including stressed, distressed and bankrupt issuers and debt obligations that are in default. In any investment involving distressed securities, there exists the risk that the transaction involving such securities will be unsuccessful. Distressed securities might be repaid only after lengthy workout or bankruptcy proceedings, during which the issuer might not make any interest or other payments. Many distressed securities are illiquid or trade in low volumes and thus may be more difficult to value.

FIXED INCOME SECURITIES RISK. An investment in the Fund also involves risk associated with an investment in fixed-income securities including the risk that certain of the securities in the Fund may not have the benefit of covenants which would prevent the issuer from engaging in capital restructurings or borrowing transactions in connection with corporate acquisitions, leveraged buyouts or restructurings which could have the effect of reducing the ability of the issuer to meet its payment obligations and might result in increased credit risk. In addition, certain of the securities may be redeemed or prepaid by the issuer, resulting in lower interest payments received by the Fund and reduced distributions to shareholders.

HIGH YIELD SECURITIES RISK. The Fund’s investment in high yield, high risk, domestic and foreign obligations, or “junk” securities, may entail increased credit risks and the risk that the value of Fund’s assets will decline, and may decline precipitously, with increases in interest rates.

Securities such as those included in the Fund are, under most circumstances, subject to greater market fluctuations and risk of loss of income and principal than are investments in lower-yielding, higher-rated securities, and their value may decline precipitously because of increases in interest rates. A slowdown in the economy, or a development adversely affecting an issuer’s creditworthiness, may result in the issuer being unable to maintain earnings or sell assets at the rate and at the prices, respectively, that are required to produce sufficient cash flow to meet its interest and principal requirements. For an issuer that has outstanding both senior commercial bank debt and subordinated high yield, high risk securities, an increase in interest rates will increase that issuer’s interest expense insofar as the interest rate on the bank debt is fluctuating. However, many leveraged issuers enter into interest rate protection agreements to fix or cap the interest rate on a large portion of their bank debt. This reduces exposure to increasing rates, but reduces the benefit to the issuer of declining rates. The Advisor cannot predict future economic policies or their consequences or, therefore, the course or extent of any similar market fluctuations in the future.

High yield debt may be issued by companies without long track records of sales and earnings, or by issuers that have questionable credit strength. High yield debt and comparable unrated debt securities: (a) will likely have some quality and protective characteristics that, in the judgment of the rating agency evaluating the instrument, are outweighed by large uncertainties or major risk exposures to adverse conditions; and (b) are predominantly speculative with respect to the issuer’s capacity to pay dividends or interest and repay principal in accordance with the terms of the obligation. Many lower-quality debt securities are subject to legal or contractual restrictions limiting the Fund's ability to resell the securities to the general public.

INCOME RISK. If interest rates decline, the income earned from the Fund's portfolio may also decline. This can result because the Fund generally holds floating rate debt that will adjust lower with falling interest rates. For loans, interest rates typically reset periodically.

INTEREST RATE RISK. The value of the Fund’s debt securities will fluctuate in value with changes in interest rates. In general, debt securities will increase in value when interest rates fall and decrease in value when interest rates rise. The Fund may be subject to a greater risk of rising interest rates than would normally be the case due to the current period of historically low rates and the effect of potential government fiscal policy initiatives and resulting market reaction to those initiatives.

Interest rate risk is generally lower for shorter term investments and higher for longer term investments. Duration is a common measure of interest rate risk. Duration measures a debt security’s expected life on a present value basis, taking into account the debt security’s yield, interest payments and final maturity. Duration is a reasonably accurate measure of a debt security’s price sensitivity to changes in interest rates. The longer the duration of a debt security, the greater the debt security’s price sensitivity is to changes in interest rates. Rising interest rates also may lengthen the duration of debt securities with call features, since exercise of the call because less likely as interest rates rise, which in turn will make the securities more sensitive to changes in interest rates and result in even steeper price declines in the event of further interest rate increases.

An increase in interest rates could also cause principal payments on a debt security to be repaid at a slower rate than expected. This risk is particularly prevalent for a callable security where an increase in interest rates could cause the issuer of that security to not redeem the security as anticipated on the call date, which could have the effect of lengthening that debt security’s expected maturity, in turn making that security more vulnerable to interest rate risk and reducing its market value.

14

When interest rates fall, the Fund may be required to reinvest the proceeds from the sale, redemption or early prepayment of a debt security at a lower interest rate.

LIBOR RISK. In 2012, regulators in the United States and the United Kingdom alleged that certain banks, including some banks serving on the panel for U.S. dollar LIBOR, engaged in manipulative acts in connection with their submissions to the British Bankers Association. Manipulation of the LIBOR rate-setting process would raise the risk to the Fund of being adversely impacted if the Fund received a payment based upon LIBOR and such manipulation of LIBOR resulted in lower resets than would have occurred had there been no manipulation. In 2017, the head of the United Kingdom’s Financial Conduct Authority announced a desire to phase out the use of LIBOR by the end of 2021. Due to the recency of this announcement, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. As such, the potential effect of a transition away from LIBOR on the Fund or the financial instruments in which the Fund invests cannot yet be determined.

LIQUIDITY RISK. The Fund invests a substantial portion of its assets in lower-quality debt instruments issued by companies that are highly leveraged. Lower-quality debt tends to be less liquid than higher-quality debt. If the economy experiences a sudden downturn, or if the debt markets for such companies become distressed, the Fund may have particular difficulty selling its assets in sufficient amounts, at reasonable prices and in a sufficiently timely manner to raise the cash necessary to meet any potentially heavy redemption requests by Fund shareholders. In such event, there would be a greater chance that the Fund may be forced to curtail or suspend redemptions, in which case you might experience a delay or inability to liquidate your investment at the desired time or in the desired amount.

NON-U.S. SECURITIES RISK. An investment in securities of non-U.S. companies involves other risks not associated with domestic issuers. Investment in non-U.S. securities may involve higher costs than investment in U.S. securities, including higher transaction and custody costs as well as the imposition of additional taxes by non-U.S. governments.

Non-U.S. investments may also involve risks associated with the level of currency exchange rates, less complete financial information about the issuers, less market liquidity, more market volatility and political instability. Future political and economic developments, the possible imposition of withholding taxes on dividend income, the possible seizure or nationalization of non-U.S. holdings, the possible establishment of exchange controls or freezes on the convertibility of currency, or the adoption of other governmental restrictions might adversely affect an investment in non-U.S. securities. Additionally, non-U.S. issuers may be subject to less stringent regulation, and to different accounting, auditing and recordkeeping requirements.

PREPAYMENT RISK. During periods of falling interest rates, an issuer of a loan may exercise its right to pay principal on an obligation earlier than expected. This may result in the Fund reinvesting proceeds at lower interest rates, resulting in a decline in the Fund’s income.

Non-Principal Risks

BORROWING AND LEVERAGE RISK. If the Fund borrows money, it must pay interest and other fees, which may reduce the Fund’s returns . Any such borrowings are intended to be temporary. However, under certain market conditions, including periods of low demand or decreased liquidity, such borrowings might be outstanding for longer periods of time. As prescribed by the 1940 Act, the Fund will be required to maintain specified asset coverage of at least 300% with respect to any bank borrowing immediately following such borrowing. The Fund may be required to dispose of assets on unfavorable terms if market fluctuations or other factors reduce the Fund’s asset coverage to less than the prescribed amount.

CREDIT RATING AGENCY RISK. Credit ratings are determined by credit rating agencies such as Standard & Poor’s, Inc., Moody’s Investors Services, Inc. and Fitch Inc., and are only the opinions of such entities. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risk or the liquidity of securities. Any shortcomings or inefficiencies in credit rating agencies’ processes for determining credit ratings may adversely affect the credit ratings of securities held by the Fund and, as a result, may adversely affect those securities’ perceived or actual credit risk.

DEPENDENCE ON KEY PERSONNEL. The Advisor is dependent upon the experience and expertise of Messrs. Housey and Fries in providing advisory services with respect to the Fund’s investments. If the Advisor were to lose the services of either of these individuals, its ability to service the Fund could be adversely affected. There can be no assurance that a suitable replacement could be found for either of Messrs. Housey or Fries in the event of their death, resignation, retirement or inability to act on behalf of the Advisor.

EMERGING MARKETS RISK. An investment in emerging market companies involves certain further risks not associated with investing in developed market countries because emerging market countries are often in the initial stages of their industrialization cycles and have low per capita income. These increased risks include the possibility of investment and trading

15

limitations, nationalization or expropriation of assets, greater liquidity concerns, higher price volatility, greater delays and possibility of disruptions in settlement transactions, greater political uncertainties and greater dependence on non-U.S. trade or development assistance. In addition, emerging market countries may be subject to overburdened infrastructures and environmental problems.

EQUITY SECURITIES RISK. Equity securities may decline significantly in price over short or extended periods of time, and such declines may occur in the equity market as a whole, or they may occur in only a particular country, company, industry or sector of the market.

FAILURE TO QUALIFY AS A REGULATED INVESTMENT COMPANY. If, in any year, the Fund fails to qualify as a regulated investment company under the applicable tax laws, the Fund would be taxed as an ordinary corporation. In such circumstances, the Fund could be required to recognize unrealized gains, pay substantial taxes and interest and make substantial distributions before requalifying as a regulated investment company that is accorded special tax treatment. If the Fund fails to qualify as a regulated investment company, distributions to the Fund's shareholders generally would be eligible (i) for treatment as qualified dividend income in the case of individual shareholders and (ii) for the dividends received deduction in the case of corporate shareholders. See "Federal Tax Matters."

INFLATION RISK. Inflation risk is the risk that the value of assets or income from investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Common stock prices may be particularly sensitive to rising interest rates, as the cost of capital rises and borrowing costs increase.

INTERNATIONAL CLOSED MARKET TRADING RISK. Because securities held by the Fund will trade on non-U.S. exchanges that are closed when the Fund's primary listing exchange is open, there are likely to be deviations between the current price of an underlying security and the last quoted price for the underlying security ( i.e. , the Fund’s quote from the closed foreign market), resulting in premiums or discounts to the Fund's net asset value that may be greater than those experienced by other ETFs. However, because shares can be created and redeemed in Creation Units at the Fund’s net asset value, it is not expected that large discounts or premiums to the net asset value of the Fund will be sustained over the long term (unlike shares of many closed-end funds, which frequently trade at appreciable discounts from, and sometimes at premiums to, their net asset values).

ISSUER SPECIFIC CHANGES RISK. The value of an individual security or particular type of security can be more volatile than the market as a whole and can perform differently from the value of the market as a whole.

INVESTMENT COMPANIES RISK . If the Fund invests in investment companies, Fund shareholders bear both their proportionate share of Fund expenses and, indirectly, the expenses of the investment companies. Also, the investment companies are subject to the risks of the underlying securities that they hold. In addition, the Fund will incur brokerage costs when purchasing and selling shares of ETFs and closed-end investment companies. Closed-end investment companies may be leveraged, in which case the value and/or yield of their shares will tend to be more volatile than shares of unleveraged funds. In addition, for index-based ETFs, the performance of an ETF may diverge from the performance of such index (commonly known as tracking error). Moreover, shares of closed-end investment companies and ETFs may be sold at a discount from their net asset value.

LEGISLATION/LITIGATION RISK . From time to time, various legislative initiatives are proposed in the United States and abroad which may have a negative impact on certain companies represented owned by the Fund. In addition, litigation regarding any of the issuers of the securities owned by the Fund, or industries represented by these issuers, may negatively impact the value of the securities. Such legislation or litigation may cause the Fund to lose value or may result in higher portfolio turnover if the Sub-Advisor determines to sell such a holding.

VALUATION RISK. Unlike publicly traded securities that trade on national exchanges, there is no central place or exchange for fixed income securities trading. Fixed income securities generally trade on an “over-the-counter” market which may be anywhere in the world where the buyer and seller can settle on a price. Due to the lack of centralized information and trading, the valuation of fixed income securities may carry more uncertainty and risk than that of publicly traded securities. Accordingly, determinations of the fair value of fixed income securities may be based on infrequent and dated information. Also, because the available information is less reliable and more subjective, elements of judgment may play a greater role in valuation of debt securities than for other types of securities. Typically, fixed income securities are valued using information provided by a third party pricing service, which primarily uses broker quotes to value the securities.

16

Fund Organization

The Fund is a series of the Trust, an investment company registered under the 1940 Act. The Fund is treated as a separate fund with its own investment objectives and policies. The Trust is organized as a Massachusetts business trust. The Trust's Board is responsible for the overall management and direction of the Trust. The Board elects the Trust’s officers and approves all significant agreements, including those with the investment advisor, custodian and fund administrative and accounting agent.

Management of the Fund

First Trust Advisors L.P., 120 East Liberty Drive, Wheaton, Illinois 60187, is the investment advisor to the Fund. In this capacity, First Trust is responsible for the investment of the Fund’s assets, managing the Fund’s business affairs and providing certain clerical, bookkeeping and other administrative services.

First Trust is a limited partnership with one limited partner, Grace Partners of DuPage L.P., and one general partner, The Charger Corporation. Grace Partners of DuPage L.P. is a limited partnership with one general partner, The Charger Corporation, and a number of limited partners. The Charger Corporation is an Illinois corporation controlled by James A. Bowen, the Chief Executive Officer of First Trust. First Trust discharges its responsibilities subject to the policies of the Board.

First Trust serves as advisor or sub-advisor for seven mutual fund portfolios, 10 exchange-traded funds consisting of 130 series and 16 closed-end funds. It is also the portfolio supervisor of certain unit investment trusts sponsored by First Trust Portfolios L.P. ( “FTP” ), an affiliate of First Trust, 120 East Liberty Drive, Wheaton, Illinois 60187. FTP specializes in the underwriting, trading and distribution of unit investment trusts and other securities. FTP is the principal underwriter of the shares of the Fund.

William Housey and Scott D. Fries are the Fund’s portfolio managers and share responsibilities for the day-to-day management of the Fund’s investment portfolio.

•

William Housey, CFA, joined First Trust in June 2010 as Senior Portfolio Manager for the Leveraged Finance Investment Team and has 21 years of investment experience. Mr. Housey is a Senior Vice President of First Trust. Prior to joining First Trust, Mr. Housey was at Morgan Stanley/Van Kampen Funds, Inc. for 11 years and served as Executive Director and Co-Portfolio Manager. Mr. Housey has extensive experience in portfolio management of both leveraged and unleveraged credit products, including bank loans, high yield bonds, credit derivatives and corporate restructurings. Mr. Housey received a BS in Finance from Eastern Illinois University and an MBA in Finance and Management and Strategy from Northwestern University’s Kellogg School of Business. He holds the FINRA Series 7, Series 52 and Series 63 licenses and the Chartered Financial Analyst designation. He is a member of the CFA Institute and the CFA Society of Chicago.

•

Scott D. Fries, CFA, joined First Trust in June 2010 as a Portfolio Manager in the Leveraged Finance Investment Team and has 23 years of investment industry experience. Mr. Fries is a Senior Vice President of First Trust. Prior to joining First Trust, Mr. Fries spent 15 years at Morgan Stanley/Van Kampen Funds, Inc., where he most recently served as Executive Director and Co-Portfolio Manager of Institutional Separately Managed Accounts. Mr. Fries received a BA in International Business from Illinois Wesleyan University and an MBA in Finance from DePaul University. Mr. Fries holds the Chartered Financial Analyst designation. He is a member of the CFA Institute and the CFA Society of Chicago.

For additional information concerning First Trust, including a description of the services provided to the Fund, see the Fund’s SAI. Additional information about the portfolio managers’ compensation, other accounts managed by the portfolio managers and the portfolio managers’ ownership of shares in the Fund is provided in the SAI.

Management Fee

Pursuant to the Investment Management Agreement, First Trust is paid an annual management fee equal to 0.85% of the Fund’s average daily net assets and is responsible for the Fund’s expenses, including the cost of transfer agency, custody, fund administration, legal, audit and other services, but excluding fee payments under the Investment Management Agreement, interest, taxes, acquired fund fees and expenses, if any, brokerage commissions and other expenses connected with the execution of portfolio transactions, distribution and service fees payable pursuant to a Rule 12b-1 plan, if any, and extraordinary expenses.

17

A discussion regarding the Board’s approval of the continuation of the Investment Management Agreement for the Fund is available in the Fund’s Annual Report to Shareholders for the fiscal year ended October 31, 2017.

How to Buy and Sell Shares

Most investors buy and sell shares of the Fund in secondary market transactions through brokers. Shares of the Fund are listed for trading on the secondary market on Nasdaq. Shares can be bought and sold throughout the trading day like other publicly traded shares. There is no minimum investment when buying shares on Nasdaq. Although shares are generally purchased and sold in “round lots” of 100 shares, brokerage firms typically permit investors to purchase or sell shares in smaller “odd lots,” at no per-share price differential. When buying or selling shares through a broker, investors should expect to incur customary brokerage commissions, investors may receive less than the net asset value of the shares because shares are bought and sold at market prices rather than net asset value and investors may pay some or all of the spread between the bid and the offer price in the secondary market on each leg of a round trip (purchase and sale) transaction. Share prices are reported in dollars and cents per share.

For purposes of the 1940 Act, the Fund is treated as a registered investment company, and, absent an available exemption or exemptive relief, the acquisition of shares by other registered investment companies and companies relying on Sections 3(c)(1) or 3(c)(7) of the 1940 Act is subject to the restrictions of Section 12(d)(1) of the 1940 Act. The Trust, on behalf of the Fund, has received an exemptive order from the Securities and Exchange Commission that permits certain registered investment companies to invest in the Fund beyond the limits set forth in Section 12(d)(1), subject to certain terms and conditions, including that any such investment companies enter into an agreement with the Fund regarding the terms of any investment.

Book Entry

Shares are held in book-entry form, which means that no share certificates are issued. The Depository Trust Company (“ DTC ”) or its nominee is the record owner of all outstanding shares of the Fund and is recognized as the owner of all shares for all purposes.

Investors owning shares are beneficial owners as shown on the records of DTC or its participants. DTC serves as the securities depository for all shares. Participants in DTC include securities brokers and dealers, banks, trust companies, clearing corporations and other institutions that directly or indirectly maintain a custodial relationship with DTC. As a beneficial owner of shares, you are not entitled to receive physical delivery of share certificates or to have shares registered in your name, and you are not considered a registered owner of shares. Therefore, to exercise any right as an owner of shares, you must rely upon the procedures of DTC and its participants. These procedures are the same as those that apply to any other stocks that you hold in book-entry or “street name” form.

Share Trading Prices

The trading price of shares of the Fund on Nasdaq is based on market price and may differ from the Fund’s daily net asset value and can be affected by market forces of supply and demand, economic conditions and other factors.

Information regarding the intra-day value of the shares of the Fund, also referred to as the “indicative optimized portfolio value” (“ IOPV ”), is disseminated every 15 seconds throughout the Fund’s trading day by the national securities exchange on which the shares are listed or by market data vendors or other information providers. The IOPV should not be viewed as a “real-time” update of the net asset value per share of the Fund because the IOPV may not be calculated in the same manner as the net asset value, which is computed once a day, generally at the end of the business day. The price of a non-U.S. security that is primarily traded on a non-U.S. exchange will be updated, using the last sale price, every 15 seconds throughout the trading day, provided that upon the closing of such non-U.S. exchange, the closing price of the security, after being converted to U.S. dollars, will be used. Furthermore, in calculating the IOPV of the Fund’s shares, exchange rates may be used throughout the day (9:00 a.m. to 4:15 p.m., Eastern Time) that may differ from those used to calculate the net asset value per share of the Fund and consequently may result in differences between the net asset value and the IOPV. The Fund is not involved in, or responsible for, the calculation or dissemination of the IOPV of shares of the Fund, and the Fund does not make any warranty as to its accuracy.

Frequent Purchases and Redemptions of the Fund’s Shares

The Fund imposes no restrictions on the frequency of purchases and redemptions (“ market timing ”). In determining not to approve a written, established policy, the Board evaluated the risks of market timing activities by the Fund’s shareholders.

18

The Board considered that the Fund’s shares can only be purchased and redeemed directly from the Fund in Creation Units by broker-dealers and large institutional investors that have entered into participation agreements ( i.e. , authorized participants (“ APs ”)), and that the vast majority of trading in the Fund’s shares occurs on the secondary market. Because the secondary market trades do not involve the Fund directly, it is unlikely those trades would cause many of the harmful effects of market timing, including: dilution, disruption of portfolio management, increases in the Fund’s trading costs and the realization of capital gains. With respect to trades directly with the Fund, to the extent effected in-kind ( i.e. , for securities), those trades do not cause any of the harmful effects that may result from frequent cash trades. To the extent that the Fund may effect the purchase or redemption of Creation Units in exchange wholly or partially for cash, the Board noted that such trades could result in dilution to the Fund and increased transaction costs, which could negatively impact the Fund’s ability to achieve its investment objectives. However, the Board noted that direct trading by APs is critical to ensuring that the shares trade at or close to net asset value. In addition, the Fund imposes fixed and variable transaction fees on purchases and redemptions of Creation Units to cover the custodial and other costs incurred by the Fund in effecting trades. Finally, the Advisor monitors purchase and redemption orders from APs for patterns of abusive trading and the Fund reserves the right to not accept orders from APs that the Advisor has determined may be disruptive to the management of the Fund, or otherwise not in the Fund’s best interests.

Dividends, Distributions and Taxes

Dividends from net investment income, if any, are declared and paid monthly by the Fund. The Fund distributes its net realized capital gains, if any, to shareholders at least annually.

Distributions in cash may be reinvested automatically in additional whole shares only if the broker through whom you purchased shares makes such option available. Such shares will generally be reinvested by the broker based upon the market price of those shares and investors may be subject to customary brokerage commissions charged by the broker.

Federal Tax Matters

This section summarizes some of the main U.S. federal income tax consequences of owning shares of the Fund. This section is current as of the date of this prospectus. Tax laws and interpretations change frequently, and these summaries do not describe all of the tax consequences to all taxpayers. For example, these summaries generally do not describe your situation if you are a corporation, a non-U.S. person, a broker-dealer, or other investor with special circumstances. In addition, this section does not describe your state, local or non-U.S. tax consequences.

This federal income tax summary is based in part on the advice of counsel to the Fund. The Internal Revenue Service could disagree with any conclusions set forth in this section. In addition, counsel to the Fund was not asked to review, and has not reached a conclusion with respect to, the federal income tax treatment of the assets to be included in the Fund. This may not be sufficient for you to use for the purpose of avoiding penalties under federal tax law.

As with any investment, you should seek advice based on your individual circumstances from your own tax advisor.

Fund Status

The Fund intends to continue to qualify or qualify as a “regulated investment company” under the federal tax laws. If the Fund qualifies as a regulated investment company and distributes its income as required by the tax law, the Fund generally will not pay federal income taxes.

Distributions

The Fund’s distributions are generally taxable. After the end of each year, you will receive a tax statement that separates the distributions of the Fund into two categories, ordinary income distributions and capital gain dividends. Ordinary income distributions are generally taxed at your ordinary tax rate, however, as further discussed below, certain ordinary income distributions received from the Fund may be taxed at the capital gains tax rates. Generally, you will treat all capital gain dividends as long-term capital gains regardless of how long you have owned your shares. To determine your actual tax liability for your capital gain dividends, you must calculate your total net capital gain or loss for the tax year after considering all of your other taxable transactions, as described below. In addition, the Fund may make distributions that represent a return of capital for tax purposes and thus will generally not be taxable to you; however, such distributions may reduce your tax basis in your shares, which could result in you having to pay higher taxes in the future when shares are sold, even if you sell the shares at a loss from your original investment. The tax status of your distributions from the Fund is not affected by whether you reinvest your distributions in additional shares or receive them in cash. The income from the Fund that you must take into account for federal

19

income tax purposes is not reduced by amounts used to pay a deferred sales fee, if any. The tax laws may require you to treat distributions made to you in January as if you had received them on December 31 of the previous year.

Income from the Fund may also be subject to a 3.8% “Medicare tax.” This tax generally applies to your net investment income if your adjusted gross income exceeds certain threshold amounts, which are $250,000 in the case of married couples filing joint returns and $200,000 in the case of single individuals.

Dividends Received Deduction

A corporation that owns shares generally will not be entitled to the dividends received deduction with respect to many dividends received from the Fund because the dividends received deduction is generally not available for distributions from regulated investment companies. However, certain ordinary income dividends on shares that are attributable to qualifying dividends received by the Fund from certain corporations may be reported by the Fund as being eligible for the dividends received deduction.

Capital Gains and Losses and Certain Ordinary Income Dividends

If you are an individual, the maximum marginal stated federal tax rate for net capital gain is generally 20% (15% or 0% for taxpayers with taxable income below certain thresholds). Some portion of your capital gain dividends from the Fund may be taxed at a higher maximum stated tax rate. Capital gains may also be subject to the Medicare tax described above.

Net capital gain equals net long-term capital gain minus net short-term capital loss for the taxable year. Capital gain or loss is long-term if the holding period for the asset is more than one year and is short-term if the holding period for the asset is one year or less. You must exclude the date you purchase your shares to determine your holding period. However, if you receive a capital gain dividend from the Fund and sell your share at a loss after holding it for six months or less, the loss will be recharacterized as long-term capital loss to the extent of the capital gain dividend received. The tax rates for capital gains realized from assets held for one year or less are generally the same as for ordinary income. The Internal Revenue Code of 1986, as amended, treats certain capital gains as ordinary income in special situations.

Ordinary income dividends received by an individual shareholder from a regulated investment company such as the Fund are generally taxed at the same rates that apply to net capital gain (as discussed above), provided certain holding period requirements are satisfied and provided the dividends are attributable to qualifying dividends received by the Fund itself. The Fund will provide notice to its shareholders of the amount of any distribution which may be taken into account as a dividend which is eligible for the capital gains tax rates.

Sale of Shares

If you sell or redeem your shares, you will generally recognize a taxable gain or loss. To determine the amount of this gain or loss, you must subtract your tax basis in your shares from the amount you receive in the transaction. Your tax basis in your shares is generally equal to the cost of your shares, generally including sales charges. In some cases, however, you may have to adjust your tax basis after you purchase your shares.

Taxes on Purchase and Redemption of Creation Units

If you exchange securities for Creation Units you will generally recognize a gain or a loss. The gain or loss will be equal to the difference between the market value of the Creation Units at the time and your aggregate basis in the securities surrendered and the cash component paid. If you exchange Creation Units for securities, you will generally recognize a gain or loss equal to the difference between your basis in the Creation Units and the aggregate market value of the securities received and the Cash Redemption Amount. The Internal Revenue Service, however, may assert that a loss realized upon an exchange of securities for Creation Units or Creation Units for securities cannot be deducted currently under the rules governing “wash sales,” or on the basis that there has been no significant change in economic position.

Treatment of Fund Expenses

Expenses incurred and deducted by the Fund will generally not be treated as income taxable to you. In some cases, however, you may be required to treat your portion of these Fund expenses as income. You may not be able to deduct some or all of these expenses.

20

Non-U.S. Tax Credit

Because the Fund may invest in non-U.S. securities, the tax statement that you receive may include an item showing non-US taxes the Fund paid to other countries. In this case, dividends taxed to you will include your share of the taxes the Fund paid to other countries. You may be able to deduct or receive a tax credit for your share of these taxes.

Non-U.S. Investors

If you are a non-U.S. investor ( i.e. , an investor other than a U.S. citizen or resident or a U.S. corporation, partnership, estate or trust), you should be aware that, generally, subject to applicable tax treaties, distributions from the Fund will be characterized as dividends for federal income tax purposes (other than dividends which the Fund properly reports as capital gain dividends) and will be subject to U.S. federal income taxes, including withholding taxes, subject to certain exceptions described below. However, distributions received by a non-U.S. investor from the Fund that are properly reported by the Fund as capital gain dividends may not be subject to U.S. federal income taxes, including withholding taxes, provided that the Fund makes certain elections and certain other conditions are met. Distributions from the Fund that are properly reported by the Fund as an interest-related dividend attributable to certain interest income received by the Fund or as a short-term capital gain dividend attributable to certain net short-term capital gain income received by the Fund may not be subject to U.S. federal income taxes, including withholding taxes when received by certain non-U.S. investors, provided that the Fund makes certain elections and certain other conditions are met.

Distributions may be subject to a U.S. withholding tax of 30% in the case of distributions to (i) certain non-U.S. financial institutions that have not entered into an agreement with the U.S. Treasury to collect and disclose certain information and are not resident in a jurisdiction that has entered into such an agreement with the U.S. Treasury and (ii) certain other non-U.S. entities that do not provide certain certifications and information about the entity’s U.S. owners. Disposition of shares by such persons may be subject to such withholding after December 31, 2018.

Investments in Certain Non-U.S. Corporations

If the Fund holds an equity interest in any passive foreign investment companies, which are generally certain non-U.S. corporations that receive at least 75% of their annual gross income from passive sources (such as interest, dividends, certain rents and royalties or capital gains) or that hold at least 50% of their assets in investments producing such passive income, the Fund could be subject to U.S. federal income tax and additional interest charges on gains and certain distributions with respect to those equity interests, even if all the income or gain is timely distributed to its shareholders. The Fund will not be able to pass through to its shareholders any credit or deduction for such taxes. The Fund may be able to make an election that could ameliorate these adverse tax consequences. In this case, the Fund would recognize as ordinary income any increase in the value of such passive foreign investment company shares, and as ordinary loss any decrease in such value to the extent it did not exceed prior increases included in income. Under this election, the Fund might be required to recognize in a year income in excess of its distributions from passive foreign investment companies and its proceeds from dispositions of passive foreign investment company stock during that year, and such income would nevertheless be subject to the distribution requirement and would be taken into account for purposes of the 4% excise tax. Dividends paid by passive foreign investment companies are not treated as qualified dividend income.

Distribution Plan

FTP serves as the distributor of Creation Units for the Fund on an agency basis. FTP does not maintain a secondary market in shares.

The Board has adopted a Distribution and Service Plan pursuant to Rule 12b-1 under the 1940 Act. In accordance with the Rule 12b-1 plan, the Fund is authorized to pay an amount up to 0.25% of its average daily net assets each year to reimburse FTP for amounts expended to finance activities primarily intended to result in the sale of Creation Units or the provision of investor services. FTP may also use this amount to compensate securities dealers or other persons that are APs for providing distribution assistance, including broker-dealer and shareholder support and educational and promotional services.

The Fund does not currently pay 12b-1 fees, and pursuant to a contractual arrangement, the Fund will not pay 12b-1 fees any time before March 31, 2019. However, in the event 12b-1 fees are charged in the future, because these fees are paid out of the Fund's assets, over time these fees will increase the cost of your investment and may cost you more than certain other types of sales charges.

21

Net Asset Value

The Fund’s net asset value is determined as of the close of trading (normally 4:00 p.m., Eastern Time) on each day the New York Stock Exchange is open for business. Net asset value is calculated for the Fund by taking the market price of the Fund’s total assets, including interest or dividends accrued but not yet collected, less all liabilities, and dividing such amount by the total number of shares outstanding. The result, rounded to the nearest cent, is the net asset value per share. All valuations are subject to review by the Board or its delegate.

The Fund’s investments are valued daily in accordance with valuation procedures adopted by the Board, and in accordance with provisions of the 1940 Act. Certain securities in which the Fund may invest are not listed on any securities exchange or board of trade. Such securities are typically bought and sold by institutional investors in individually negotiated private transactions that function in many respects like an over-the-counter secondary market, although typically no formal market makers exist. Certain securities, particularly debt securities, have few or no trades, or trade infrequently, and information regarding a specific security may not be widely available or may be incomplete. Accordingly, determinations of the fair value of debt securities may be based on infrequent and dated information. Because there is less reliable, objective data available, elements of judgment may play a greater role in valuation of debt securities than for other types of securities. Typically, debt securities are valued using information provided by a third-party pricing service. The third- party pricing service primarily uses broker quotes to value the securities.

The Fund’s investments are valued daily at market value or, in the absence of market value with respect to any portfolio securities, at fair value, in accordance with valuation procedures adopted by the Board and in accordance with the 1940 Act. Portfolio securities listed on any exchange other than Nasdaq and the London Stock Exchange Alternative Investment Market (“ AIM ”) are valued at the last sale price on the business day as of which such value is being determined. Securities listed on Nasdaq or the AIM are valued at the official closing price on the business day as of which such value is being determined. If there has been no sale on such day, or no official closing price in the case of securities traded on Nasdaq or the AIM, the securities are fair valued at the mean of the most recent bid and ask prices on such day. Portfolio securities traded on more than one securities exchange are valued at the last sale price or official closing price, as applicable, on the business day as of which such value is being determined at the close of the exchange representing the principal market for such securities. Portfolio securities traded in the over-the-counter market, but excluding securities trading on Nasdaq or the AIM, are fair valued at the mean of the most recent bid and asked price, if available, and otherwise at the closing bid price. Short-term investments that mature in less than 60 days when purchased are fair valued at cost adjusted for amortization of premiums and accretion of discount, provided the Advisor’s Pricing Committee has determined that the use of amortized cost is an appropriate reflection of fair value given market and issuer-specific conditions existing at the time of determination. Net asset value may change on days when investors may not sell or redeem Fund shares.

Senior Loans in which the Fund invests are not listed on any securities exchange or board of trade. Senior Loans are typically bought and sold by institutional investors in individually negotiated private transactions that function in many respects like an over-the-counter secondary market, although typically no formal market-makers exist. This market, while having grown substantially since its inception, generally has fewer trades and less liquidity than the secondary market for other types of securities. Some Senior Loans have few or no trades, or trade infrequently, and information regarding a specific Senior Loan may not be widely available or may be incomplete. Accordingly, determinations of the market value of Senior Loans may be based on infrequent and dated information. Because there is less reliable, objective data available, elements of judgment may play a greater role in valuation of Senior Loans than for other types of securities. Typically, Senior Loans are fair valued using information provided by a third-party pricing service. The third-party pricing service primarily uses over-the-counter pricing from dealer runs and broker quotes from indicative sheets to value the Senior Loans.

Certain securities may not be able to be priced by pre-established pricing methods. Such securities may be valued by the Board or its delegate, the Advisor’s Pricing Committee, at fair value. The use of fair value pricing by the Fund is governed by valuation procedures adopted by the Board and in accordance with the provisions of the 1940 Act. These securities generally include, but are not limited to, certain restricted securities (securities which may not be publicly sold without registration under the Securities Act) for which a pricing service is unable to provide a market price; securities whose trading has been formally suspended; a security whose market or fair value price is not available from a pre-established pricing source; a security with respect to which an event has occurred that is likely to materially affect the value of the security after the market has closed but before the calculation of the Fund’s net asset value or make it difficult or impossible to obtain a reliable market quotation; and a security whose price, as provided by the pricing service, does not reflect the security’s fair value. As a general principle, the current fair value of a security would appear to be the amount which the owner might reasonably expect to receive for

22

the security upon its current sale. When fair value prices are used, generally they will differ from the current market valuations. See the Fund’s SAI for details.

Because foreign securities exchanges may be open on different days than the days during which an investor may purchase or sell shares of the Fund, the value of the Fund’s securities may change on days when investors are not able to purchase or sell shares of the Fund. The value of securities denominated in foreign currencies is converted into U.S. dollars at the exchange rates in effect at the time of valuation.

Fund Service Providers

The Bank of New York Mellon, 101 Barclay Street, New York, New York 10286, acts as the administrator, custodian and fund accounting and transfer agent for the Fund. Chapman and Cutler LLP, 111 West Monroe Street, Chicago, Illinois 60603, serves as legal counsel to the Fund.

Premium/Discount Information

The table that follows presents information about the differences between the Fund’s daily market price on Nasdaq and its net asset value. The “Market Price” of the Fund generally is determined using the midpoint between the highest bid and lowest offer on Nasdaq, as of the time the Fund’s net asset value is calculated. The Fund’s Market Price may be at, above, or below its net asset value. The net asset value of the Fund will fluctuate with changes in the market value of its portfolio holdings. The Market Price of the Fund will fluctuate in accordance with changes in its net asset value, as well as market supply and demand.

Premiums or discounts are the differences (generally expressed as a percentage) between the net asset value and Market Price of the Fund on a given day, generally at the time net asset value is calculated. A premium is the amount that the Fund is trading above the reported net asset value. A discount is the amount that the Fund is trading below the reported net asset value.

The following information shows the frequency distribution of premiums and discounts of the daily bid/ask price of the Fund against the Fund’s net asset value. The information shown for the Fund is for the period indicated. Shareholders may pay more than net asset value when they buy Fund shares and receive less than net asset value when they sell those shares because shares are bought and sold at current market price. All data presented here represents past performance, which cannot be used to predict future results. Information about the premiums and discounts at which the Fund’s shares have traded is available on the Fund’s website at www.ftportfolios.com.

First Trust Senior Loan Fund (FTSL)

Bid/Ask Midpoint vs. Net Asset Value

Number of Days Bid/Ask Midpoint At/Above Net Asset Value

	0.00% – 0.49%	0.50% – 0.99%	1.00% – 1.99%	>=2.00%
12 Months Ended 12/31/2017	227	0	0	0

Number of Days Bid/Ask Midpoint Below Net Asset Value

	0.00% – 0.49%	0.50% – 0.99%	1.00% – 1.99%	>=2.00%
12 Months Ended 12/31/2017	24	0	0	0

Total Return Information

The table below compares the total return of the Fund to two specialty market indices. The information presented for the Fund is for the period indicated.

“Average annual total returns” represent the average annual change in the value of an investment over the period indicated. “Cumulative total returns” represent the total change in value of an investment over the period indicated. The net asset value per share of the Fund is the value of one share of the Fund and is computed by dividing the value of all assets of the Fund

23

(including accrued interest and dividends), less liabilities (including accrued expenses and dividends declared but unpaid), by the total number of outstanding shares. The net asset value return is based on the net asset value per share of the Fund, and the market return is based on the market price per share of the Fund. The price used to calculate market return ( “Market Price” ) generally is determined by using the midpoint between the highest bid and the lowest offer on Nasdaq as of the time that the Fund's net asset value is calculated. Since the shares of the Fund typically do not trade in the secondary market until several days after the Fund's inception, for the period from inception to the first day of secondary market trading in shares of the Fund, the net asset value of the Fund is used as a proxy for the secondary market trading price to calculate market returns. Market and net asset value returns assume that all distributions have been reinvested in the Fund at Market Price and net asset value, respectively. An index is a statistical composite that tracks a specified financial market or sector. Unlike the Fund, an index does not actually hold a portfolio of securities and therefore does not incur the expenses incurred by the Fund. These expenses negatively impact the performance of the Fund. Also, market returns do not include brokerage commissions that may be payable on secondary market transactions. If brokerage commissions were included, market returns would be lower. The total returns reflect the reinvestment of dividends on securities in the indices. The returns shown in the table below do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or the redemption or sale of shares of the Fund. The investment return and principal value of shares of the Fund will vary with changes in market conditions. Shares of the Fund may be worth more or less than their original cost when they are redeemed or sold in the market. The Fund's past performance is no guarantee of future results.

First Trust Senior Loan Fund (FTSL)

Total Returns as of October 31, 2017

		Average Annual		Cumulative
	1 Year	Inception (5/1/2013)		Inception (5/1/2013)
Fund Performance
Net Asset Value	3.43%	2.98%		14.14%
Market Price	3.51%	3.02%		14.32%
Index Performance
Markit iBoxx USD Liquid Leveraged Loan Index	3.10%	2.47%		11.62%
S&P/LSTA U.S. Leveraged Loan 100 Index	4.42%	3.06%		14.53%

  

24

Financial Highlights

The financial highlights table is intended to help you understand the Fund's financial performance for the periods shown. Certain information reflects financial results for a single share of the Fund. The total returns represent the rate that an investor would have earned (or lost) on an investment in the Fund (assuming reinvestment of all dividends and distributions). The information for the periods indicated has been derived from financial statements audited by Deloitte & Touche LLP, whose report, along with the Fund's financial statements, is included in the Fund's Annual Report to Shareholders dated October 31, 2017 and is incorporated by reference in the Fund's SAI, which is available upon request.

First Trust Exchange-Traded Fund IV

Financial Highlight
For a share outstanding throughout each period

First Trust Senior Loan Fund (FTSL)

(a)	Inception date is consistent with the commencement of investment operations and is the date the initial creation units were established.
(b)	Total return is calculated assuming an initial investment made at the net asset value at the beginning of the period, reinvestment of all distributions at net asset value during the period, and redemption at net asset value on the last day of the period. The returns presented do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or the redemption or sale of Fund shares. Total return is calculated for the time period presented and is not annualized for periods of less than a year.
(c)	Annualized.
(d)	Portfolio turnover is calculated for the time period presented and is not annualized for periods of less than a year and does not include securities received or delivered from processing creations or redemptions and in-kind transactions.

25

Other Information

Continuous Offering

The Fund issues, on a continuous offering basis, its shares in one or more groups of a fixed number of Fund shares (each such group of such specified number of individual Fund shares, a “Creation Unit Aggregation” ). The method by which Creation Unit Aggregations of Fund shares are created and traded may raise certain issues under applicable securities laws. Because new Creation Unit Aggregations of shares are issued and sold by the Fund on an ongoing basis, a “distribution,” as such term is used in the Securities Act, may occur at any point. Broker-dealers and other persons are cautioned that some activities on their part may, depending on the circumstances, result in their being deemed participants in a distribution in a manner which could render them statutory underwriters and subject them to the prospectus delivery requirement and liability provisions of the Securities Act.

For example, a broker-dealer firm or its client may be deemed a statutory underwriter if it takes Creation Unit Aggregations after placing an order with FTP, breaks them down into constituent shares and sells such shares directly to customers, or if it chooses to couple the creation of a supply of new shares with an active selling effort involving solicitation of secondary market demand for shares. A determination of whether one is an underwriter for purposes of the Securities Act must take into account all the facts and circumstances pertaining to the activities of the broker-dealer or its client in the particular case, and the examples mentioned above should not be considered a complete description of all the activities that could lead to a characterization as an underwriter.

Broker-dealer firms should also note that dealers who are not “underwriters” but are effecting transactions in shares, whether or not participating in the distribution of shares, are generally required to deliver a prospectus. This is because the prospectus delivery exemption in Section 4(a)(3) of the Securities Act is not available in respect of such transactions as a result of Section 24(d) of the 1940 Act. As a result, broker-dealer firms should note that dealers who are not underwriters but are participating in a distribution (as contrasted with ordinary secondary market transactions) and thus dealing with the shares that are part of an overallotment within the meaning of Section 4(a)(3)(C) of the Securities Act would be unable to take advantage of the prospectus delivery exemption provided by Section 4(a)(3) of the Securities Act. Firms that incur a prospectus delivery obligation with respect to shares are reminded that, under the Securities Act Rule 153, a prospectus delivery obligation under Section 5(b)(2) of the Securities Act owed to a broker-dealer in connection with a sale on Nasdaq is satisfied by the fact that the prospectus is available from Nasdaq upon request. The prospectus delivery mechanism provided in Rule 153 is available with respect to transactions on a national securities exchange, a trading facility or an alternative trading system.

26

      

[THIS PAGE INTENTIONALLY LEFT BLANK.]

First Trust Senior Loan Fund

For More Information

For more detailed information on the Fund, several additional sources of information are available to you. The SAI, incorporated by reference into this prospectus, contains detailed information on the Fund's policies and operation. Additional information about the Fund's investments is available in the annual and semi-annual reports to shareholders. In the Fund's annual report, you will find a discussion of the market conditions and investment strategies that significantly impacted the Fund's performance during the last fiscal year. The Fund's most recent SAI, annual and semi-annual reports and certain other information are available free of charge by calling the Fund at (800) 621-1675, on the Fund's website at www.ftportfolios.com or through your financial advisor. Shareholders may call the toll-free number above with any inquiries.

You may obtain this and other information regarding the Fund, including the SAI and the Codes of Ethics adopted by First Trust, FTP and the Trust, directly from the Securities and Exchange Commission (the “SEC” ). Information on the SEC’s website is free of charge. Visit the SEC’s online EDGAR database at www.sec.gov or in person at the SEC’s Public Reference Room in Washington, D.C., or call the SEC at (202) 551-8090 for information on the Public Reference Room. You may also request information regarding the Fund by sending a request (along with a duplication fee) to the SEC’s Public Reference Section, 100 F Street, N.E., Washington, D.C. 20549-1520 or by sending an electronic request to publicinfo@sec.gov.

First Trust Advisors L.P.
120 East Liberty Drive, Suite 400
Wheaton, Illinois 60187
(800) 621-1675
www.ftportfolios.com

SEC File #: 333-174332

811-22559

Prospectus

First Trust SSI Strategic Convertible Securities ETF

Ticker Symbol:	FCVT
Exchange:	Nasdaq

First Trust SSI Strategic Convertible Securities ETF (the “ Fund ”) lists and principally trades its shares on The Nasdaq Stock Market LLC (“ Nasdaq ” or the “ Exchange ”). Market prices may differ to some degree from the net asset value of the shares. Unlike mutual funds, the Fund issues and redeems shares, at net asset value, only in large specified blocks each consisting of 50,000 shares (each such block of shares called a “ Creation Unit ” and, collectively, the “ Creation Units ”). The Fund’s Creation Units are generally issued and redeemed for cash and, in certain circumstances, in-kind for securities in which the Fund invests, and only to and from broker-dealers and large institutional investors that have entered into participation agreements.

The Fund is a series of First Trust Exchange-Traded Fund IV (the " Trust ") and an actively managed exchange-traded fund organized as a separate series of a registered management investment company.

Except when aggregated in Creation Units, the shares are not redeemable securities of the Fund.

The Securities and Exchange Commission has not approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

Table of Contents

Summary Information	3
Additional Information on the Fund's Investment Objective and Strategies	12
Fund Investments	12
Additional Risks of Investing in the Fund	18
Fund Organization	22
Management of the Fund	22
How to Buy and Sell Shares	24
Dividends, Distributions and Taxes	25
Federal Tax Matters	25
Distribution Plan	28
Net Asset Value	28
Fund Service Providers	29
Premium/Discount Information	29
Total Return Information	30
Financial Highlights	31
Other Information	32

Investment Objective

The First Trust SSI Strategic Convertible Securities ETF's (the " Fund ") investment objective is to seek total return.

Fees and Expenses of the Fund

The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund. Investors purchasing and selling shares may be subject to costs (including customary brokerage commissions) charged by their broker, which are not reflected in the table below.

Shareholder Fees
(fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

None

    

Annual Fund Operating Expenses
(expenses that you pay each year as a percentage of the value of your investment)

Management Fees	0.95%
Distribution and Service (12b-1) Fees (1)	0.00%
Other Expenses	0.00%
Net Annual Fund Operating Expenses	0.95%

(1)	Although the Fund has adopted a 12b-1 plan that permits it to pay up to 0.25% per annum, it will not pay 12b-1 fees at any time before March 31, 2019.

Example

The example below is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. This example does not take into account customary brokerage commissions that you pay when purchasing or selling shares of the Fund in the secondary market.

The example assumes that you invest $10,000 in the Fund for the time periods indicated. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain at current levels until March 31, 2019, and thereafter at 1.20% to represent the imposition of the 12b-1 fee of 0.25% per annum of the Fund’s average daily net assets. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

1 Year	3 Years	5 Years	10 Years
$97	$356	$636	$1,432

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 56% of the average value of its portfolio.

Principal Investment Strategies

To the extent permitted under applicable law, percentage limitations described in this prospectus are generally as of the time of investment by the Fund and may be exceeded on a going-forward basis as a result of market fluctuations affecting the Fund’s portfolio securities.

Under normal market conditions, the Fund seeks to achieve its investment objective by investing at least 80% of its net assets (including investment borrowings) in a portfolio of U.S. and non-U.S. convertible securities (described below). In general, convertible securities combine the investment characteristics of bonds and common stocks and typically consist of debt securities or preferred securities that may be converted or exchanged within a specified period of time (typically for the entire life of the security) into a certain amount of common stock or other equity security (such equity securities referred to as “ underlying securities ”) of the same or a different issuer (and/or the cash equivalent thereof). A convertible security is designed to provide current income and also the potential for capital appreciation through the conversion feature, which enables the

3

holder to benefit from increases (if any) in the market price of the underlying equity security. Accordingly, these equity-linked instruments offer the potential for equity market participation along with, in light of their bond-like characteristics, potential mitigated downside risk (which is generally the risk that a security may suffer a decline in value) in periods of equity market declines.

The Fund may invest in the following convertible securities (collectively, the “ Convertible Securities ”):

•	Convertible and exchangeable notes, bonds and debentures;
•	Convertible preferred securities;
•	Mandatory convertible securities (Conversion is not optional for these convertible securities, which automatically convert on maturity.);
•	Contingent convertible securities (These convertible securities may provide for conversion under certain circumstances, including, for example: if a company fails to meet the minimum amount of capital described in the security; if the company’s regulator makes a determination that the security should convert; or if the company receives specified levels of extraordinary public support. Additionally, contingent convertible securities may contain features that limit an investor’s ability to convert the convertible security into its underlying security unless certain conditions are met, including, for example, when the sale price of the underlying security exceeds the conversion price by a specified percentage for a certain specified period of time.);
•	Synthetic convertible securities (These convertible securities (a) consist of two or more distinct securities whose economic characteristics, when taken together, resemble those of traditional convertible securities ( i.e. , an income-producing security and the right to acquire an equity security (through, for example, an option or a warrant)); or (b) are exchangeable or equity-linked securities issued by a broker-dealer, investment bank or other financial institution with proceeds going directly to the broker-dealer, investment bank or other financial institution, as applicable, that have economic characteristics similar to those of traditional convertible securities.);
•	Corporate bonds and preferred securities with attached warrants; and
•	Convertible securities that are eligible for purchase and sale pursuant to Rule 144A under the Securities Act of 1933, as amended (the “ Securities Act ”) (such as, for example, convertible securities that are issued in private placements).

In selecting securities for the Fund, SSI Investment Management Inc., the Fund’s sub-advisor (the “ Sub-Advisor ”), utilizes both quantitative and fundamental analysis to construct a portfolio of Convertible Securities intended to provide an attractive level of returns typically associated with investments in equity securities, but with a degree of downside protection that is provided through bond-like characteristics. Through its investment process, the Sub-Advisor attempts to identify attractive Convertible Securities based on its positive view of the underlying security or its view of the company’s potential for credit improvement. The Sub-Advisor screens the universe for Convertible Securities that present the most attractive reward per unit of risk. Once attractive Convertible Securities have been identified, the Sub-Advisor generally uses fundamental equity and credit analysis to determine which of the attractive Convertible Securities it believes have a sound underlying security with potential for increase in value. In conjunction with its analysis, the Sub-Advisor reviews the overall economic situation. In this regard, the Fund is actively managed, whereby, the Sub-Advisor assesses the position of the economic cycle and the performance outlook for certain economic sectors. In making decisions to purchase or sell Convertible Securities, the Sub-Advisor will, at times, over- or underweight different economic sectors, market capitalizations, and credit quality exposures relative to the available universe of Convertible Securities. The Sub-Advisor may also adjust the sensitivity of the portfolio to movements in the equity market and to interest rates based on the macroeconomic outlook. The Fund may manage the market exposure defensively during periods of market distress.

The Fund may invest in Convertible Securities of any credit quality, including securities that are rated below investment grade or unrated, and with effective or final maturities of any length. Below investment grade securities are commonly referred to as “ junk ” or “ high yield ” securities and are considered speculative with respect to the issuer’s capacity to pay interest and repay principal. The Fund’s investment advisor expects that, under normal market conditions, generally, for a Convertible Security to be considered as an eligible investment, after taking into account such an investment, at least 75% of the Fund’s net assets that are invested in Convertible Securities will be comprised of Convertible Securities that will have, at the time of original issuance, $200 million or more in par amount outstanding.

The Fund will limit its investments in synthetic convertible securities to 10% of its net assets (calculated at the time of investment). The Fund’s investments in options will be limited to options that represent a component of a synthetic convertible security.

4

The Fund may invest, without limit, in securities that have not been registered under the Securities Act and continue to be subject to restrictions on resale, securities held by control persons of the issuer and securities that are subject to contractual restrictions on their resale (collectively, “ restricted securities ”). Restricted securities include, without limitation, securities eligible for purchase and sale pursuant to Rule 144A under the Securities Act (“ Rule 144A ”) and other securities issued in private placements. Under normal market conditions, the Fund will limit its investments in Convertible Securities that are Rule 144A securities to securities with $100 million or more in principal amount outstanding as of the time of their original issuance.

In addition to investing in Convertible Securities, the Fund also may invest in the following securities and instruments. The Fund may invest up to 20% of its net assets in exchange-traded notes (“ ETNs ”), which are a type of senior, unsecured, unsubordinated debt security issued by financial institutions that combines both aspects of bonds and exchange-traded funds (“ ETFs ”). The Fund may invest up to 20% of its net assets in equity securities listed on domestic or foreign securities exchanges, including, but not limited to, American Depositary Receipts (“ ADRs ”), Global Depositary Receipts (“ GDRs ”), equity securities of business development companies (“ BDCs ”), and equity securities held upon conversion of Convertible Securities into their corresponding underlying securities. In addition, the Fund may invest in exchange-listed futures contracts on equity indexes, exchange-listed and over-the-counter (“ OTC ”) index credit default swaps, and forward foreign currency exchange contracts; however, the Fund will limit the aggregate notional value of its positions in these instruments (calculated at the time of investment) to 20% of the value of its net assets.

The Fund is classified as “non-diversified” under the Investment Company Act of 1940, as amended (the “ 1940 Act ”).

Principal Risks

You could lose money by investing in the Fund. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. There can be no assurance that the Fund’s investment objective will be achieved.

AUTHORIZED PARTICIPANT CONCENTRATION RISK. Only an authorized participant (as defined in the “Frequent Purchases and Redemptions” Section) may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of institutions that act as authorized participants. To the extent that these institutions exit the business or are unable to proceed with creation and/or redemption orders with respect to the Fund and no other authorized participant is able to step forward to create or redeem, in either of these cases, Fund shares may trade at a discount to the Fund’s net asset value and possibly face delisting.

BDC RISK. The Fund may invest in BDCs which may carry risks similar to those of a private equity or venture capital fund. Investments in BDCs may be subject to price volatility and lack of liquidity. Debt securities and preferred securities issued by BDCs may be rated below investment grade (referred to as “junk” bonds), including in the lowest possible rating category, or unrated. Shares of BDCs are not redeemable at the option of the shareholder and they may trade in the market at a discount to their net asset value. Moreover, a shareholder of a BDC will indirectly bear its pro rata share of the fees and expenses incurred by the BDC in which it invests, including advisory fees. The BDCs held by the Fund may employ the use of leverage through borrowings or the issuance of preferred stock. This leverage also subjects a BDC to increased risks, including the likelihood of increased volatility and the possibility that a BDC’s common share income will fall if the dividend rate of the preferred shares or the interest rate on any borrowings rises. The loss on a leveraged investment may far exceed the principal amount invested. Moreover, the use of leverage may result in a BDC having to liquidate holdings when it may not be advantageous to do so. Investments in BDCs include risks associated with their holdings of smaller issuers and private companies. A BDC may make investments with a larger amount of risk of volatility and loss of principal than other investment options and may also be highly speculative and aggressive. For example, BDCs may invest in the debt of a company, which involves risk that the company may default on its payments or declare bankruptcy, and many of the debt instruments in which a BDC may invest will not be rated by a credit rating agency and may be below investment grade quality (referred to as “junk” bonds). A BDC’s investments are generally less liquid than publicly traded securities and are subject to restrictions on their resale. The illiquidity of a BDC’s holdings may make it difficult for the BDC to sell such investments if the need arises, and thus the BDC may be unable to take advantage of market opportunities or it may be forced to sell illiquid securities at a loss if it is required to raise cash for operations. Some BDCs are listed and trade on an exchange and other BDCs are not traded on an exchange and trade only in private transactions. BDCs that are not traded on an exchange may be less liquid than those that are traded on an exchange. An investment in BDCs may result in a complete loss of the investment.

CASH TRANSACTIONS RISK. The Fund will, under most circumstances, effect a significant portion of creations and redemptions for cash, rather than in-kind securities. As a result, an investment in the Fund may be less tax-efficient than an investment in

5

an ETF that effects its creations and redemptions for in-kind securities. Because the Fund may effect a portion of redemptions for cash, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. A sale of shares may result in capital gains or losses and may also result in higher brokerage costs.

CONVERTIBLE SECURITIES RISK. Convertible securities have characteristics of both equity and debt securities and, as a result, are exposed to certain additional risks. If a convertible security held by the Fund is called for redemption or conversion, the Fund could be required to tender it for redemption, convert it into the underlying equity security or sell it to a third party, which may have an adverse effect on the Fund’s ability to achieve its investment objective. The market values of convertible securities tend to decline as interest rates increase. However, a convertible security’s market value also tends to reflect the market price of the equity security of the issuing company, particularly when the price of the equity security is greater than the convertible security’s conversion price ( i.e ., the predetermined price or exchange ratio at which the convertible security can be converted or exchanged for the underlying equity security). Convertible securities are also exposed to the risk that an issuer is unable to meet its obligation to make dividend or principal payments when due as a result of changing financial or market conditions. Convertible securities generally offer lower interest or dividend yields than non-convertible debt securities of similar credit quality because of their potential for capital appreciation. Moreover, there can be no assurance that convertible securities will provide current income prior to conversion because the issuers of the convertible securities may default on their obligations.

Mandatory convertible securities are a subset of convertible securities. The conversion of such securities is not optional, and the conversion price at maturity is based solely upon the market price of the underlying equity security, which may be significantly less than par or the price (above or below par) paid. Mandatory convertible securities generally are subject to a greater risk of loss of value than securities convertible at the option of the holder.

Contingent convertible securities (which generally provide for conversion under certain circumstances) are also a subset of convertible securities. They may have some of the characteristics of high yield bonds (referred to as “junk” bonds), while providing exposure to equity-like losses and volatility. Similar to mandatory convertible securities (and unlike traditional convertible securities), some contingent convertible securities provide for mandatory conversion under certain circumstances. The mandatory conversion might be automatically triggered, for instance, if a company fails to meet the minimum amount of capital described in the security, the company’s regulator makes a determination that the security should convert or the company receives specified levels of extraordinary public support. Additionally, contingent convertible securities may contain features that limit an investor’s ability to convert the security into the underlying equity security unless certain conditions are met. A typical feature may require that a security be convertible only when the sale price of the underlying common stock exceeds the conversion price by a specified percentage ( e.g ., the sale price of the common stock is greater than or equal to 130% of the conversion price) for a certain specified period of time ( e.g. , for at least 20 days during a span of 30 consecutive days in a month), or upon the occurrence of certain other specified conditions. Also, since the common stock of the issuer may not pay a dividend, investors in these instruments could experience a reduced income rate, potentially to zero, and conversion would deepen the subordination of the investor, hence worsening standing in a bankruptcy. Further, some contingent convertible securities have a set stock conversion rate that would cause a reduction in value of the security if the price of the stock is below the conversion price on the conversion date. Additionally, some contingent convertible securities have characteristics designed to absorb losses, where the liquidation value of the security may be adjusted downward to below the original par value or written off entirely under certain circumstances. The write-down of the security’s par value may occur automatically and would not entitle holders to institute bankruptcy proceedings against the issuer. In addition, an automatic write-down could result in a reduced income rate if the dividend or interest payment associated with the security is based on the security’s par value. Moreover, various contingent convertible securities may contain features that limit an investor’s ability to convert the security unless certain conditions are met.

The values of certain synthetic convertible securities will respond differently to market fluctuations than a traditional convertible security because such synthetic convertibles are composed of two or more separate securities or instruments, each with its own market value. In addition, if the value of the underlying equity security or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value. Synthetic convertible securities created by other parties generally have economic characteristics similar to those of a traditional convertible security; however, the issuer of the synthetic convertible security assumes the credit risk associated with the investment, rather than the issuer of the underlying equity security into which the instrument is convertible. Therefore, the Fund is subject to the credit risk associated with the counterparty creating the synthetic convertible instrument. Synthetic convertible securities may also be subject to additional liquidity risk and to the risks associated with derivatives.

6

CREDIT RISK. Credit risk is the risk that an issuer of a security will be unable or unwilling to make dividend, interest and/or principal payments when due and the related risk that the value of a security may decline because of concerns about the issuer’s ability to make such payments. Credit risk may be heightened if the Fund invests in “high yield” or “junk” securities; such securities involve greater risks than investment grade debt securities with similar maturities, including the possibility of dividend or interest deferral, default or bankruptcy, and are regarded as predominantly speculative with respect to the issuer’s capacity to pay dividends or interest and repay principal.

CURRENCY RISK. The Fund may hold investments that are denominated in non-U.S. currencies, or in securities that provide exposure to such currencies, currency exchange rates or interest rates denominated in such currencies. Changes in currency exchange rates and the relative value of non-U.S. currencies will affect the value of the Fund’s investments and the value of Fund shares. Currency exchange rates can be very volatile and can change quickly and unpredictably. As a result, the value of an investment in the Fund may change quickly and without warning and you may lose money.

CYBER SECURITY RISK. As the use of Internet technology has become more prevalent in the course of business, the Fund has become more susceptible to potential operational risks through breaches in cyber security. A breach in cyber security refers to both intentional and unintentional events that may cause the Fund to lose proprietary information, suffer data corruption or lose operational capacity. Such events could cause the Fund to incur regulatory penalties, reputational damage, additional compliance costs associated with corrective measures and/or financial loss. Cyber security breaches may involve unauthorized access to the Fund’s digital information systems through “hacking” or malicious software coding, but may also result from outside attacks such as denial-of-service attacks through efforts to make network services unavailable to intended users. In addition, cyber security breaches of the Fund’s third party service providers, such as its administrator, transfer agent, custodian, or sub-advisor, as applicable, or issuers in which the Fund invests, can also subject the Fund to many of the same risks associated with direct cyber security breaches. The Fund has established risk management systems designed to reduce the risks associated with cyber security. However, there is no guarantee that such efforts will succeed, especially because the Fund does not directly control the cyber security systems of issuers or third party service providers.

DEBT SECURITIES RISK. An investment in the Fund involves risk associated with an investment in debt securities including the risk that certain of the securities in the Fund may not have the benefit of covenants that would prevent the issuer from engaging in capital restructurings or borrowing transactions in connection with corporate acquisitions, leveraged buyouts or restructurings. This limitation could reduce the ability of the issuer to meet its payment obligations and might result in increased credit risk. In addition, certain of the securities may be redeemed or prepaid by the issuer, resulting in lower interest payments received by the Fund and reduced distributions to shareholders.

DEPOSITARY RECEIPTS RISK. Depositary receipts may be less liquid than the underlying shares in their primary trading market. Any distributions paid to the holders of depositary receipts are usually subject to a fee charged by the depositary. Holders of depositary receipts may have limited voting rights, and investment restrictions in certain countries may adversely impact the value of depositary receipts because such restrictions may limit the ability to convert shares into depositary receipts and vice versa. Such restrictions may cause shares of the underlying issuer to trade at a discount or premium to the market price of the depositary receipts.

DERIVATIVES RISK. The use of swaps, options, futures contracts, forward contracts and other derivatives can lead to losses because of adverse movements in the price or value of the underlying asset, index or rate, which may be magnified by certain features of the derivatives. These risks are heightened when the Fund’s portfolio managers use derivatives to enhance the Fund’s return or as a substitute for a position or security, rather than solely to hedge (or offset) the risk of a position or security held by the Fund.

EQUITY SECURITIES RISK. The Fund may hold equity securities in its portfolio through direct investments in equity securities or upon conversion of a convertible security. The value of the Fund’s shares will fluctuate with changes in the value of these equity securities. Equity securities prices fluctuate for several reasons, including changes in investors’ perceptions of the financial condition of an issuer or the general condition of the relevant stock market, such as market volatility, or when political or economic events affecting the issuers occur. In addition, common stock prices may be particularly sensitive to rising interest rates, as the cost of capital rises and borrowing costs increase.

ETNS RISK. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are subject to credit risk, and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility

7

and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating and economic, legal, political or geographic events that affect the referenced underlying asset.

FLUCTUATION OF NET ASSET VALUE RISK . The net asset value of shares of the Fund will generally fluctuate with changes in the market value of the Fund’s holdings. The market prices of shares will generally fluctuate in accordance with changes in net asset value as well as the relative supply of and demand for shares on the Exchange. The Fund’s investment advisor cannot predict whether shares will trade below, at or above their net asset value because the shares trade on the Exchange at market prices and not at net asset value. Price differences may be due, in large part, to the fact that supply and demand forces at work in the secondary trading market for shares will be closely related to, but not identical to, the same forces influencing the prices of the holdings of the Fund trading individually or in the aggregate at any point in time. However, given that shares can only be purchased and redeemed either in-kind or for cash in Creation Units, and only to and from broker-dealers and large institutional investors that have entered into participation agreements (unlike shares of closed-end funds, which frequently trade at appreciable discounts from, and sometimes at premiums to, their net asset value), the Fund’s investment advisor believes that large discounts or premiums to the net asset value of shares should not be sustained.

FORWARD CURRENCY EXCHANGE CONTRACTS RISK. Forward foreign currency exchange contracts involve certain risks, including the risk of failure of the counterparty to perform its obligations under the contract and the risk that the use of forward contracts may not serve as a complete hedge because of an imperfect correlation between movements in the prices of the contracts and the prices of the currencies hedged. While forward foreign currency contracts may limit the risk of loss due to a decline in the value of the hedged currencies, they also may limit any potential gain that might result should the value of the currencies increase.

FUTURES CONTRACTS RISK. The primary risks associated with the use of futures contracts are (i) the imperfect correlation between the change in market value of the instruments held by the Fund and the price of the futures contract; (ii) possible lack of a liquid secondary market for a futures contract and the resulting inability to close a futures contract when desired; (iii) losses caused by unanticipated market movements, which are potentially unlimited; (iv) the Sub-Advisor’s inability to predict correctly the direction of securities prices, interest rates, currency exchange rates and other economic factors; (v) the possibility that the counterparty will default in the performance of its obligations; and (vi) if the Fund has insufficient cash, it may have to sell securities from its portfolio to meet daily variation margin requirements, and the Fund may have to sell securities at a time when it may be disadvantageous to do so.

HIGH YIELD SECURITIES RISK. High yield securities, or “junk” bonds, are subject to greater market fluctuations and risk of loss than securities with higher ratings, and therefore, are considered to be highly speculative. These securities are issued by companies that may have limited operating history, narrowly focused operations and/or other impediments to the timely payment of periodic interest and principal at maturity. If the economy slows down or dips into recession, the issuers of high yield securities may not have sufficient resources to continue making timely payment of periodic interest and principal at maturity. The market for high yield securities is generally smaller and less liquid than that for investment grade securities. High yield securities are generally not listed on a national securities exchange but trade in the over-the-counter markets. Due to the smaller, less liquid market for high yield securities, the bid-offer spread on such securities is generally greater than it is for investment grade securities and the purchase or sale of such securities may take longer to complete. In general, high yield securities may have a greater risk of default than other types of securities.

ILLIQUID SECURITIES RISK. Illiquid securities involve the risk that the securities will not be able to be sold at the time desired by the Fund or at prices approximately the value at which the Fund values the securities.

INCOME RISK. Income from the Fund's fixed income investments could decline during periods of falling interest rates.

INDEX CREDIT DEFAULT SWAPS RISK. Index credit default swap transactions involve greater risks than if the Fund had invested in the reference obligations directly. In addition to general market risks, index credit default swaps are subject to liquidity risk, counterparty risk and credit risks. With respect to a reference obligation, a buyer will lose its investment and recover nothing should no event of default occur. For a seller, if an event of default were to occur, the value of the reference obligation received by the seller, coupled with the periodic payments previously received, may be less than the full notional value it pays to the buyer, resulting in a loss of value. When the Fund acts as a seller of an index credit default swap agreement, it is exposed to the risks of leverage since if an event of default occurs with respect to a reference obligation, the seller must pay the buyer the full notional value of the reference obligation.

INFORMATION TECHNOLOGY COMPANIES RISK. Information technology companies are generally subject to the following risks: rapidly changing technologies; short product life cycles; fierce competition; aggressive pricing and reduced profit margins;

8

the loss of patent, copyright and trademark protections; cyclical market patterns; evolving industry standards; and frequent new product introductions. Information technology companies may be smaller and less experienced companies, with limited product lines, markets or financial resources and fewer experienced management or marketing personnel. Information technology company stocks, especially those which are Internet related, have experienced extreme price and volume fluctuations that are often unrelated to their operating performance.

INTEREST RATE RISK. Interest rate risk is the risk that the value of the debt securities in the Fund’s portfolio will decline because of rising market interest rates. Interest rate risk is generally lower for shorter term debt securities and higher for longer term debt securities. Duration is a measure of the expected price volatility of a debt instrument as a result of changes in market rates of interest, based on, among other factors, the weighted average timing of the instrument’s expected principal and interest payments. In general, duration represents the expected percentage change in the value of a security for an immediate 1% change in interest rates. Therefore, prices of debt securities with shorter durations tend to be less sensitive to interest rate changes than debt securities with longer durations. As the value of a debt security changes over time, so will its duration.

MANAGEMENT RISK. The Fund is subject to management risk because it is an actively managed portfolio. In managing the Fund’s investment portfolio, the Fund’s Sub-Advisor will apply investment techniques and risk analyses that may not have the desired result. There can be no guarantee that the Fund will meet its investment objective.

MARKET MAKER RISK. If the Fund has lower average daily trading volumes, it may rely on a small number of third-party market makers to provide a market for the purchase and sale of shares. Any trading halt or other problem relating to the trading activity of these market makers could result in a dramatic change in the spread between the Fund’s net asset value and the price at which the Fund’s shares are trading on the Exchange which could result in a decrease in value of the Fund’s shares. In addition, decisions by market makers or authorized participants to reduce their role or step away from these activities in times of market stress could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the underlying values of the Fund’s portfolio securities and the Fund’s market price. This reduced effectiveness could result in Fund shares trading at a discount to net asset value and also in greater than normal intraday bid-ask spreads for Fund shares.

MARKET RISK. Market risk is the risk that a particular security owned by the Fund or shares of the Fund in general may fall in value. Securities are subject to market fluctuations caused by such factors as economic, political, regulatory or market developments, changes in interest rates and perceived trends in securities prices. Shares of the Fund could decline in value or underperform other investments.

NON-DIVERSIFICATION RISK. The Fund is classified as “non-diversified” under the 1940 Act. As a result, the Fund is only limited as to the percentage of its assets which may be invested in the securities of any one issuer by the diversification requirements imposed by the Internal Revenue Code of 1986, as amended. The Fund may invest a relatively high percentage of its assets in a limited number of issuers. As a result, the Fund may be more susceptible to a single adverse economic or regulatory occurrence affecting one or more of these issuers, experience increased volatility and be highly invested in certain issuers.

NON-U.S. SECURITIES RISK. Non-U.S. securities are subject to higher volatility than securities of domestic issuers due to possible adverse political, social or economic developments, restrictions on foreign investment or exchange of securities, lack of liquidity, currency exchange rates, excessive taxation, government seizure of assets, different legal or accounting standards, and less government supervision and regulation of exchanges in foreign countries.

PREFERRED SECURITIES RISK. Preferred securities combine some of the characteristics of both common stocks and bonds. Preferred securities are typically subordinated to bonds and other debt instruments in a company’s capital structure, in terms of priority to corporate income, and therefore will be subject to greater credit risk than those debt instruments. Preferred securities are also subject to credit risk, interest rate risk and income risk.

RESTRICTED SECURITIES RISK. Investments in restricted securities could have the effect of increasing the amount of the Fund’s assets invested in illiquid securities if qualified institutional buyers are unwilling to purchase these securities. Illiquid and restricted securities may be difficult to dispose of at the price at which the Fund has valued the securities and at the times when the Fund believes it is desirable to do so. The market price of illiquid and restricted securities generally is more volatile than that of more liquid securities, which may adversely affect the price that the Fund recovers upon the sale of such securities. Investment of the Fund’s assets in illiquid and restricted securities may restrict the Fund’s ability to take advantage of market opportunities.

TRADING ISSUES RISK . Although the shares of the Fund are listed for trading on the Exchange, there can be no assurance that an active trading market for such shares will develop or be maintained. Trading in shares on the Exchange may be halted

9

due to market conditions or for reasons that, in the view of the Exchange, make trading in shares inadvisable. In addition, trading in shares on the Exchange is subject to trading halts caused by extraordinary market volatility pursuant to the Exchange’s “circuit breaker” rules. Market makers are under no obligation to make a market in the Fund’s shares, and authorized participants are not obligated to submit purchase or redemption orders for Creation Units. There can be no assurance that the requirements of the Exchange necessary to maintain the listing of the Fund will continue to be met or will remain unchanged. In particular, if the Fund does not comply with any provision of the listing standards of the Exchange that are applicable to the Fund, and cannot bring itself into compliance within a reasonable period after discovering the matter, the Exchange may remove the shares of the Fund from listing. The Fund may have difficulty maintaining its listing on the Exchange in the event the Fund’s assets are small or the Fund does not have enough shareholders.

WARRANTS RISK. The prices of warrants, which entitle the holder to purchase equity securities at specific prices for a certain period of time, do not necessarily move parallel to the prices of the underlying securities and likely fluctuate more than the prices of the underlying securities. Warrants have no voting rights, receive no dividends, and have no rights with respect to the assets of the issuer.

Annual Total Return

The bar chart and table below illustrate the annual calendar year returns of the Fund based on net asset value as well as the average annual Fund returns. The bar chart and table provide an indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year-to-year and by showing how the Fund’s average annual total returns based on net asset value compared to those of a broad-based securities market index. See “Total Return Information” for additional performance information regarding the Fund. The Fund’s performance information is accessible on the Fund’s website at www.ftportfolios.com.

Returns before taxes do not reflect the effects of any income or capital gains taxes. All after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of any state or local tax. Returns after taxes on distributions reflect the taxed return on the payment of dividends and capital gains. Returns after taxes on distributions and sale of shares assume you sold your shares at period end, and, therefore, are also adjusted for any capital gains or losses incurred. Returns for the market indices do not include expenses, which are deducted from Fund returns, or taxes.

Your own actual after-tax returns will depend on your specific tax situation and may differ from what is shown here. After-tax returns are not relevant to investors who hold Fund shares in tax-deferred accounts such as individual retirement accounts ( IRAs ) or employee-sponsored retirement plans.

First Trust SSI Strategic Convertible Securities ETF
Calendar Year Total Returns as of 12/31

During the periods shown in the chart above:

Best Quarter		Worst Quarter
5.14%	March 31, 2017	-0.97%	March 31, 2016

The Fund’s past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

10

Average Annual Total Returns for the Periods Ended December 31, 2017

(1)	Effective October 22, 2017, the index name changed from BofA Merill Lynch All US Convertibles Index to ICE BofAML All US Convertibles Index.

11

Additional Information on the Fund's Investment Objective and Strategies

The Fund’s investment objective is fundamental and may not be changed without approval by the holders of a majority of the outstanding voting securities of the Fund. Unless an investment policy is identified as being fundamental, all investment policies included in this prospectus and the Fund’s Statement of Additional Information (“ SAI ”) are non-fundamental and may be changed by the Board of Trustees (the “ Board ”) of First Trust Exchange-Traded Fund IV (the “ Trust ”), of which the Fund is a series, without shareholder approval. If there is a material change to the Fund’s principal investment strategies, you should consider whether the Fund remains an appropriate investment for you. The Fund has adopted a non-fundamental investment policy pursuant to Rule 35d-1 under the 1940 Act (the “ Name Policy ”) whereby the Fund, under normal market conditions, invests at least 80% of its net assets (including investment borrowings) in Convertible Securities. The Name Policy may be changed by the Board of Trustees without shareholder approval upon 60 days’ prior written notice.

There is no guarantee that the Fund will achieve its investment objective. During the initial invest-up period, the Fund may depart from its principal investment strategies and invest a larger amount or all of its assets in cash or cash equivalents.

Fund Investments

Principal Investments

Convertible Securities

Convertible securities are generally bonds, debentures, notes, preferred securities or other securities or investments that may be converted or exchanged into equity securities (and/or the cash equivalent thereof), which may be at a stated exchange ratio or predetermined price (the “ conversion price ”). A convertible security is designed to provide current income and also the potential for capital appreciation through the conversion feature, which enables the holder to benefit from increases (if any) in the market price of the underlying equity security. Accordingly, these equity-linked instruments offer the potential for equity market participation along with, in light of their bond-like characteristics, potential mitigated downside risk (which is generally the risk that a security may suffer a decline in value) in periods of equity market declines.

A convertible security generally entitles the holder to receive interest paid or accrued until the convertible security matures or is redeemed, converted or exchanged. Before conversion, convertible securities have characteristics similar to non-convertible debt obligations and are designed to provide for a stable stream of income with generally higher yields than common stocks. However, there can be no assurance of current income because the issuers of the convertible securities may default on their obligations.

Convertible securities rank senior to common stock in a corporation’s capital structure and, therefore, generally entail less risk than the corporation’s common stock. Convertible debt securities may be subordinate in rank to any senior debt obligations of the issuer and, therefore, such subordinated convertible debt securities entail more risk than its senior debt obligations.

A convertible security may be called for redemption or conversion by the issuer after a particular date and under certain circumstances (including a specified price) established upon issue. If a convertible security held by the Fund is called for redemption or conversion, the Fund could be required to tender it for redemption, convert it into the underlying equity security or sell it to a third party, which may have an adverse effect on the Fund’s ability to achieve its investment objective.

Convertible securities have valuation characteristics similar to both debt and equity securities. Convertible securities generally offer lower interest or dividend yields than non-convertible debt securities of similar credit quality because of the potential for capital appreciation. The value of convertible securities is influenced by both the yield of non-convertible securities of comparable issuers and by the value of the underlying equity security. The value of a convertible security viewed without regard to its conversion feature ( i.e ., strictly on the basis of its yield) is sometimes referred to as its “investment value.” The investment value of the convertible security typically will fluctuate based on the credit quality of the issuer and will fluctuate inversely with changes in prevailing interest rates. However, at the same time, the value of a convertible security will be influenced by its “conversion value,” which is the market value of the underlying equity security that would be obtained if the convertible security were converted. Conversion value fluctuates directly with the price of the underlying equity security, and will therefore be subject to risks relating to the activities of the issuer of the underlying equity security and general market and economic conditions. Depending upon the relationship of the conversion price to the market value of the underlying security, a convertible security may trade more like an equity security than a debt instrument.

12

If, because of a low price of the underlying equity security, the conversion value is substantially below the investment value of the convertible security, the price of the convertible security is governed principally by its investment value. Generally, if the conversion value of a convertible security increases to a point that approximates or exceeds its investment value, the value of the security will be principally influenced by its conversion value. A convertible security will sell at a premium over its conversion value to the extent investors place value on the right to acquire the underlying equity security while holding an income-producing security.

Debt and preferred securities with warrants attached to purchase equity securities have many characteristics of convertible securities and their prices may, to some degree, reflect the performance of the underlying equity security. A warrant is a right to purchase an equity security at a specific price (usually at a premium above the market value of the underlying equity security at the time of issuance) during a specified period of time.

Contingent Convertible Securities . Contingent convertible securities (which generally provide for conversion under certain circumstances) are distinguished as a subset of convertible securities. Similar to mandatory convertible securities (and unlike traditional convertible securities), some contingent convertible securities provide for mandatory conversion under certain circumstances. The mandatory conversion might be automatically triggered, for instance, if a company fails to meet the minimum amount of capital described in the security, the company’s regulator makes a determination that the security should convert or the company receives specified levels of extraordinary public support. Since the common stock of the issuer may not pay a dividend, investors in these instruments could experience a reduced income rate, potentially to zero, and conversion would deepen the subordination of the investor, hence worsening standing in a bankruptcy. Further, some contingent convertible securities have a set stock conversion rate that would cause a reduction in value of the security if the price of the stock is below the conversion price on the conversion date. In addition, various contingent convertible securities may contain features that limit an investor’s ability to convert the security unless certain conditions are met.

Exchangeable Debt Securities . Exchangeable debt securities are convertible debt securities in which the underlying equity security is issued by an entity that is different from the issuer of the convertible securities, often a subsidiary of the issuer. The valuation of an exchangeable debt security is similar to that of a convertible debt security, with the conversion value influenced by the issuer of the underlying equity security.

Mandatory Convertible Securities . Mandatory convertible securities are distinguished as a subset of convertible securities because the conversion is not optional and the conversion price at maturity (or redemption) is based solely upon the market price of the underlying equity security, which may be significantly less than par or the price (above or below par) paid. Mandatory convertible securities automatically convert to equity securities at maturity. For these reasons, the risks associated with investing in mandatory convertible securities most closely resemble the risks inherent in equity securities. Mandatory convertible securities customarily pay a higher coupon yield to compensate for the potential risk of additional price volatility and loss upon redemption. Since the correlation of common stock risk increases as the security approaches its redemption date, there can be no assurance that the higher coupon will compensate for the potential loss.

Synthetic Convertible Securities . Some synthetic convertible securities consist of two or more distinct securities whose economic characteristics, when taken together, resemble those of traditional convertible securities ( i.e ., an income producing component and the convertible component). For example, the income producing component may be achieved by purchasing non-convertible securities such as bonds, preferred securities or money market instruments and the convertible component may be achieved through warrants or options to buy common stock at a certain exercise price, or options on a stock index. Other synthetic convertible securities include exchangeable or equity-linked securities issued by a broker-dealer, investment bank or other financial institution with proceeds going directly to the broker-dealer, investment bank or other financial institution, as applicable, that have economic characteristics similar to those of traditional convertible securities.

Synthetic convertibles are typically offered by financial institutions in private placement transactions and are typically sold back to the offering institution. Upon conversion, the holder generally receives from the offering institution shares and/or cash of the then-current value of the underlying securities.

Synthetic convertible securities may differ from traditional convertible securities in several respects. The value of a synthetic convertible is the sum of the values of its income producing component and its convertible component. Thus, the values of a synthetic convertible and a traditional convertible security will respond differently to market fluctuations. Purchasing a synthetic convertible security may provide greater flexibility than purchasing a traditional convertible security, including the ability to combine components representing distinct issuers or to combine a fixed income security with a call option on a stock index. In addition, synthetic convertible securities may alter the characteristics common to traditional convertible securities

13

such as by offering enhanced yields in exchange for reduced capital appreciation or less downside protection. The component parts of a synthetic convertible security may be purchased simultaneously or separately.

The holder of a synthetic convertible faces the risk that the price of the stock, or the level of the market index underlying the convertible component, will decline. In addition, in purchasing a synthetic convertible security, a Fund may have counterparty risk with respect to the financial institution that offers the instrument or with respect to the institution that issued the income producing component of the convertible security when such an institution is not the financial institution creating the synthetic convertible security. Synthetic convertible securities are also subject to additional liquidity risk and to the risks associated with derivatives.

Synthetic convertible securities include convertible structured notes, which are income producing debentures linked to equity and are typically issued by investment banks. Convertible structured notes have the attributes of a convertible security. However, the credit risk that the Fund assumes on purchasing such a security pertains to the investment bank that issues the convertible note, rather than the issuer of the underlying equity security into which the note is convertible.

Debt Securities

Debt securities include obligations typically issued by corporations to borrow money from investors, such as corporate bonds, debentures and notes. These securities may be either secured or unsecured. Holders of debt securities, as creditors, have a prior legal claim over common and preferred shareholders as to both income and assets of the issuer for the principal and interest due them and may have a prior claim over other creditors if liens or mortgages are involved. Interest on debt securities is typically paid semi-annually and is fully taxable to the holder of the securities. The investment return of debt securities reflects interest on the security and changes in the market value of the security. The market value of a fixed rate debt security generally may be expected to rise and fall inversely with changes in interest rates and also may be affected by the credit rating of the issuer, the issuer’s performance and perceptions of the issuer in the marketplace. Debt securities issued by corporations usually have a higher yield than government or agency bonds due to the presence of credit risk. Certain of the debt securities in which the Fund may invest may be rated below investment grade (commonly referred to as “junk” or “high yield” securities).

Exchange-Traded Notes . ETNs are a type of senior, unsecured, unsubordinated debt security issued by financial institutions that combines both aspects of bonds and ETFs. An ETN’s returns are based on the performance of a market index minus fees and expenses. Similar to ETFs, ETNs are listed on an exchange and traded in the secondary market. However, unlike an ETF, an ETN can be held until the ETN’s maturity, at which time the issuer is obligated to pay a return linked to the performance of the market index to which the ETN is linked minus certain fees. Unlike regular bonds, ETNs do not make periodic interest payments and principal is not protected. When the Fund invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Fund’s decision to sell its ETN holdings may be limited by the availability of a secondary market. In addition, although an ETN may be listed on an exchange, the issuer may not be required to maintain the listing and there can be no assurance that a secondary market will exist for an ETN.

High Yield Securities . The Fund may invest in securities of any credit quality, including securities that are rated below investment grade. Below investment grade securities are rated below “BBB-” by Standard & Poor’s Ratings Group, a division of The McGraw-Hill Companies (“ S&P ”), or Fitch Ratings, Inc. (“ Fitch ”), below “Baa3” by Moody’s Investors Service, Inc. (“ Moody’s ”) or comparably rated by another nationally recognized statistical rating organization (“ NRSRO ”) or, if unrated, determined by the Sub-Advisor to be of comparable credit quality at the time of purchase. Below investment grade securities are commonly referred to as “junk” or “high yield” securities and are considered speculative with respect to the issuer’s capacity to pay interest and repay principal.

Equity Securities

The Fund may hold equity securities in its portfolio through direct investments in equity securities or upon conversion of a Convertible Security into its corresponding underlying security. Equity securities include common and preferred stocks, depositary receipts, and equity interests in BDCs. An investment in the equity securities of a company represents a proportionate ownership interest in that company. Therefore, the Fund participates in the financial success or failure of any company in which it has an equity interest.

Business Development Companies . BDCs are a type of closed-end fund regulated under the 1940 Act that typically invest in and lend to small and medium-sized private and certain public companies that may not have access to public equity markets for capital raising. BDCs invest in such diverse industries as healthcare, chemical and manufacturing, technology and service companies. BDCs are unique in that at least 70% of their investments must be made in private and certain public U.S. businesses, and BDCs are required to make available significant managerial assistance to their portfolio companies. Unlike corporations,

14

BDCs are not taxed on income distributed to their shareholders provided they comply with the applicable requirements of the Internal Revenue Code of 1986, as amended. BDCs, which are required to distribute substantially all of their income to investors in order to not be subject to entity level taxation, often offer a yield advantage over other types of securities. The Fund will indirectly bear its proportionate share of any management and other expenses, and of any performance based or incentive fees, charged by the BDCs in which it invests, in addition to the expenses paid by the Fund. The Fund is permitted to invest in BDCs in excess of the limits imposed under the 1940 Act pursuant to an exemptive order obtained by the Trust and the Advisor.

Common Stock . Traditional convertible securities are typically converted into common stocks. Common stocks represent residual ownership interest in issuers and holders of common stocks are entitled to the income and increase in the value of the assets and business of the issuers after all debt obligations and obligations to preferred stockholders are satisfied. Common stocks generally have voting rights. Common stocks fluctuate in price in response to many factors including historical and prospective earnings of the issuer, the value of its assets, general economic conditions, interest rates, investor perceptions and market liquidity. The value of common stocks purchased by the Fund could decline if the financial condition of the companies the Fund invests in declines or if overall market and economic conditions deteriorate. Their value also may decline due to factors that affect a particular industry or industries, such as labor shortages or an increase in production costs and competitive conditions within an industry. In addition, they may decline due to general market conditions that are not specifically related to a company or industry, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or generally adverse investor sentiment.

Preferred Securities . Preferred securities represent an equity ownership interest in the issuer, but generally entitle the holder to receive, in preference to the holders of other stocks such as common stocks, dividends and a fixed share of the proceeds resulting from liquidation of the company. Some preferred securities also entitle their holders to receive additional liquidation proceeds on the same basis as holders of a company’s common stock. Some preferred securities offer a fixed rate of return with no maturity date. Because those preferred securities never mature, they act like long-term bonds, can be more volatile than other types of preferred securities and may have heightened sensitivity to changes in interest rates. Other preferred securities have a variable dividend, generally determined on a quarterly or other periodic basis, either according to a formula based upon a specified premium or discount to the yield on particular U.S. Treasury securities or based on an auction process, involving bids submitted by holders and prospective purchasers of such stocks. Because preferred securities represent an equity ownership interest in a company, their value usually will react more strongly than bonds and other debt instruments to actual or perceived changes in the company’s financial condition or prospects or to fluctuations in the equity markets. Holders of preferred securities generally have no voting rights or their voting rights are limited to certain extraordinary transactions or events.

Non-U.S. Investments

Non-U.S. investments include securities issued or guaranteed by companies organized under the laws of countries other than the United States, including companies domiciled in emerging markets. Non-U.S. investments may be traded on foreign securities exchanges or in over-the-counter capital markets. Many non-U.S. companies issue both foreign currency and U.S. dollar-denominated securities. The Fund may also invest in ADRs and GDRs, or other securities representing underlying securities of non-U.S. issuers.

ADRs are typically issued by a financial institution (a depositary) and evidence ownership interests in a security or a pool of securities issued by a non-U.S. company and deposited with the depositary. Generally, ADRs in registered form are dollar-denominated securities designed for use in the U.S. securities markets. GDRs are receipts issued outside the United States, typically by non-United States banks and trust companies, that evidence ownership of either non-U.S. or domestic securities. Generally, GDRs are designed for use outside the United States. ADRs and GDRs may be issued as sponsored or unsponsored programs. In sponsored programs, an issuer has made arrangements to have its securities trade in the form of ADRs or GDRs. Unsponsored ADR and GDR programs are organized independently and without the cooperation of the issuer of the underlying securities. The Fund will only invest in sponsored ADRs and GDRs.

In connection with its non-U.S. investments, to protect the value of its portfolio against uncertainty in the level of future currency exchange rates, the Fund may enter into foreign currency transactions on a spot ( i.e., cash) basis or it may enter into forward foreign currency exchange contracts (described below).

Derivative Instruments

The Fund may invest in exchange-listed futures contracts on equity indexes, exchange-listed and OTC index credit default swaps, and forward foreign currency exchange contracts; however, the Fund will limit the aggregate notional value of its

15

positions in these instruments (calculated at the time of investment) to 20% of the value of its net assets. The Fund will enter into the foregoing transactions to seek to manage the risks of the Fund’s portfolio securities or for investment or other purposes to the extent the Sub-Advisor determines that their use would be consistent with the investment objective and policies of the Fund, as well as applicable regulatory requirements. Generally, derivatives are financial contracts whose values depend upon, or are derived from, the value of an underlying asset, reference rate or index, and may relate to, among others, individual debt instruments, interest rates, currencies or currency exchange rates, commodities and related indexes. Certain of the Fund’s derivative transactions may provide investment leverage to the Fund’s portfolio.

The Fund’s investments in derivative instruments will be consistent with the Fund’s investment objective and the 1940 Act and will not be used to seek to achieve a multiple or inverse multiple of an index. The Fund will only enter into transactions in OTC index credit default swaps and forward foreign currency exchange contracts with counterparties that the Advisor and/or the Sub-Advisor reasonably believes are capable of performing under the applicable agreement.

Futures Contracts . The Fund may invest in exchange-listed futures contracts that provide long or short exposure to an underlying equity index, either for hedging or investment purposes. A futures contract may generally be described as an agreement between two parties to buy and sell particular financial instruments for an agreed price during a designated month or to deliver the final cash settlement price in the case of a contract relating to an index or otherwise not calling for physical delivery at the end of trading in the contract. The price at which the contract trades (the “ contract price ”) is determined by relative buying and selling interest on a regulated exchange. The Fund’s use of futures contracts will in all cases be consistent with applicable regulatory requirements, including the rules and regulations of the Commodity Futures Trading Commission.

Transaction costs are incurred when a futures contract is bought or sold and margin deposits must be maintained. Margin is the amount of funds equal to a specified percentage of the current market value of the contract that must be deposited by the Fund with its custodian in the name of the futures commission merchant in order to initiate futures trading and to maintain the Fund’s open positions in futures contracts. A margin deposit is intended to ensure the Fund’s performance of the futures contract. The margin required for a particular futures contract is set by the exchange on which the futures contract is traded and may be significantly modified from time to time by the exchange during the term of the futures contract.

Index Credit Default Swap Agreements . The Fund may invest in exchange-listed and OTC index credit default swap agreements. A swap is a financial instrument that typically involves the exchange of cash flows between two parties on specified dates, where the cash flows are based on agreed-upon prices, rates, indexes, etc. The Fund may be either the buyer or seller in an index credit default swap transaction. The buyer in a credit default contract is obligated to pay the seller a periodic stream of payments over the term of the contract, provided, that no event of default on an underlying reference obligation has occurred. If an event of default occurs, the seller must pay the buyer the full notional value, or “par value,” of the reference obligation. Credit default swap transactions are either “physical delivery” settled or “cash” settled. Physical delivery entails the actual delivery of the reference asset to the seller in exchange for the payment of the full par value of the reference asset. Cash settled entails a net cash payment from the seller to the buyer based on the difference of the par value of the reference asset and the current value of the reference asset that may have, through default, lost some, most or all of its value. If no event of default occurs, the buyer will have made a series of periodic payments and recover nothing of monetary value. However, if an event of default occurs, the buyer will receive the full notional value of the reference obligation either through a cash payment in exchange for the asset or a cash payment in addition to owning the reference assets. The seller receives a fixed rate of income throughout the term of the contract, which typically is between six months and five years, provided, that there is no event of default. If an event of default occurs, the seller must pay the buyer the full notional value of the reference obligation.

An index credit default swap is a swap on an index of credit default swaps. Index credit default swaps allow an investor to manage credit risk or to take a position on a basket of credit default swaps (or other instruments) in a more efficient manner than transacting in single name credit default swaps. If a credit event occurs in one of the underlying companies, the protection is paid out via the delivery of the defaulted bond by the buyer of protection in return for payment of the notional value of the defaulted bond by the seller of protection or it may be settled through a cash settlement between the two parties. The underlying company is then removed from the index.

Forward Foreign Currency Exchange Contracts . To protect the value of its portfolio against uncertainty in the level of future currency exchange rates, as noted above, the Fund may enter into foreign currency transactions on a spot ( i.e ., cash) basis or it may enter into forward foreign currency exchange contracts. A forward foreign currency exchange contract is an obligation to purchase or sell a specific currency at a future date, which may be any fixed number of days agreed upon by the parties from the date of the contract, at a price set on the date of the contract. The Fund expects to invest in forward foreign currency exchange contracts for hedging or currency risk management purposes and not in order to speculate on currency exchange

16

rate movements, and the amount the Fund may invest in such transactions is limited to the extent of its non-U.S. investments. The Fund will only enter into forward foreign currency exchange contracts with parties which it believes to be creditworthy.

Restricted Securities/Rule 144A Securities

Restricted securities include, without limitation, securities eligible for purchase and sale pursuant to Rule 144A and other securities issued in private placements. A restriction on public sale of restricted securities may make it more difficult to value the securities, limit the Fund’s ability to dispose of them and lower the amount the Fund could realize upon their sale. Rule 144A provides a non-exclusive safe harbor exemption from the registration requirements of the Securities Act for the resale of certain securities to certain qualified institutional buyers, such as the Fund. Any resale of these securities must generally be effected through a sale that is registered under the Securities Act or otherwise exempted or excepted from such registration requirements. To the extent privately placed securities held by the Fund qualify under Rule 144A and an institutional market develops for those securities, the Fund likely will be able to dispose of the securities without registering them under the Securities Act. To the extent that institutional buyers become, for a time, uninterested in purchasing these securities, investing in Rule 144A securities could increase the level of the Fund’s illiquidity. The restricted securities held by the Fund that are also Convertible Securities will be treated as such for purposes of the Fund’s policy to invest, under normal market conditions, at least 80% of its net assets in Convertible Securities. In addition, restricted securities determined by the Sub-Advisor to be illiquid are subject to the limitation on the amount of illiquid securities in which the Fund may invest.

Non-Principal Investments

Cash Equivalents and Short-Term Investments

Under normal market conditions, the Fund may invest up to 20% of its net assets in short-term debt securities and other short-term debt instruments (described below), as well as cash equivalents, or it may hold cash. The percentage of the Fund’s net assets invested in such holdings will vary and depend on several factors, including market conditions. For purposes of the foregoing investment policy, short-term debt securities shall be securities from issuers having a long-term debt rating of at least “A” from S&P, Moody’s or Fitch and shall have a maturity of one year or less. The Fund may invest in the following short-term debt instruments: (i) fixed rate and floating rate U.S. government securities, including bills, notes and bonds differing as to maturity and rates of interest, which are either issued or guaranteed by the U.S. Treasury or by U.S. government agencies or instrumentalities; (ii) certificates of deposit issued against funds deposited in a bank or savings and loan association; (iii) bankers’ acceptances, which are short-term credit instruments used to finance commercial transactions; (iv) repurchase agreements, which involve purchases of debt securities and shall only be entered into with financial institutions and dealers believed by the Advisor and/or the Sub-Advisor to present minimal credit risks; (v) bank time deposits, which are monies kept on deposit with banks or savings and loan associations for a stated period of time at a fixed rate of interest; (vi) commercial paper, which are short-term unsecured promissory notes and shall be rated “A-1” or higher by S&P, “Prime-1” or higher by Moody’s or “F1” or higher by Fitch; and (vii) corporate debt obligations.

For temporary defensive purposes and during periods of high cash inflows or outflows, the Fund may depart from its principal investment strategies and invest part or all of its assets in these securities or it may hold cash. During such periods, the Fund may not be able to achieve its investment objective. The Fund may adopt a defensive strategy when the portfolio managers believe securities in which the Fund normally invests have elevated risks due to political or economic factors and in other extraordinary circumstances. For more information on eligible short-term investments, see the SAI.

Illiquid Securities

The Fund may invest up to 15% of its net assets in securities and other instruments that are, at the time of investment, illiquid (determined using the Securities and Exchange Commission’s standard applicable to investment companies, i.e., securities that cannot be disposed of by the Fund within seven days in the ordinary course of business at approximately the amount at which the Fund has valued the securities). For purposes of the foregoing investment policy, illiquid securities may include, but are not limited to, restricted securities.

Disclosure of Portfolio Holdings

A description of the policies and procedures with respect to the disclosure of the Fund's portfolio securities is included in the Fund's SAI, which is available on the Fund's website at www.ftportfolios.com.

17

Additional Risks of Investing in the Fund

Risk is inherent in all investing. Investing in the Fund involves risk, including the risk that you may lose all or part of your investment. There can be no assurance that the Fund will meet its stated objective. Before you invest, you should consider the following supplemental disclosure pertaining to the Principal Risks set forth above as well as additional Non-Principal Risks set forth below in this prospectus.

Principal Risks

BUSINESS DEVELOPMENT COMPANY RISK. The Fund may invest in BDCs which may carry risks similar to those of a private equity or venture capital fund. Securities that are not publicly registered may be difficult to value and may be difficult to sell at a price representative of their intrinsic value. Small and medium-sized companies also may have fewer lines of business so that changes in any one line of business may have a greater impact on the value of their stock than is the case with a larger company. An investment in BDCs is also subject to additional risks, including management’s ability to meet the fund’s investment objective, and to manage the fund’s portfolio when the underlying securities are redeemed or sold, during periods of market turmoil and as investors’ perceptions regarding the funds or their underlying investments change. BDCs are not redeemable at the option of the shareholder and they may trade in the market at a discount to their net asset value.

The BDCs included in the Fund may employ the use of leverage in their portfolios through borrowings or the issuance of preferred stock. While leverage often serves to increase the yield of a BDC, this leverage also subjects a BDC to increased risks, including the likelihood of increased volatility and the possibility that a BDC’s common share income will fall if the dividend rate of the preferred shares or the interest rate on any borrowings rises.

CASH TRANSACTIONS RISK. The Fund intends to effect a significant portion of creations and redemptions for cash, rather than in-kind securities. As a result, an investment in the Fund may be less tax-efficient than an investment in an ETF that effects its creations and redemptions for in-kind securities. ETFs are able to make in-kind redemptions and avoid being taxed on gains on the distributed portfolio securities at the fund level. Because the Fund intends to effect a significant portion of redemptions for cash, rather than in-kind distributions, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. Any recognized gain on these sales by the Fund will generally cause the Fund to recognize a gain it might not otherwise have recognized, or to recognize such gain sooner than would otherwise be required if it were to distribute portfolio securities in-kind. The Fund distributes these gains to shareholders to avoid being taxed on this gain at the fund level and otherwise comply with the special tax rules that apply to it. This strategy may cause shareholders to be subject to tax on gains they would not otherwise be subject to, or at an earlier date than if they had made an investment in a different ETF. Moreover, cash transactions may have to be carried out over several days if the securities market is relatively illiquid, and such transactions may involve considerable brokerage fees and taxes. These brokerage fees and taxes, which will be higher than if the Fund sold and redeemed its shares principally in-kind, will be passed on to those purchasing and redeeming Creation Units in the form of creation and redemption transaction fees. In addition, these factors may result in wider spreads between the bid and the offered prices of the Fund's shares than for ETFs that distribute portfolio securities in-kind.

CREDIT RISK. Credit risk is the risk that an issuer of a debt instrument, futures or other instrument may be unable or unwilling to make dividend, interest and/or principal payments when due and the related risk that the value of an instrument may decline because of concerns about the issuer’s ability or unwillingness to make such payments. High yield and comparable unrated debt securities involve greater risks than investment grade debt with similar maturities, including the possibility of dividend or interest deferral, default or bankruptcy, and are regarded as predominantly speculative with respect to the issuer's capacity to pay dividends or interest and repay principal.

CURRENCY RISK. An investment in non-U.S. securities involves risk due to currency exchange rates. Changes in currency exchange rates and the relative value of non-U.S. currencies will affect the value of the Fund’s investments and the value of your Fund shares. Changes in currency exchange rates also may affect the value of interest earned and gains and losses realized on the sale of securities. Currency exchange rates can be very volatile and can change quickly and unpredictably. As a result, the value of an investment in the Fund may change quickly and without warning and you may lose money.

An increase in the strength of the U.S. dollar relative to other currencies may cause the value of the Fund to decline. Certain non-U.S. currencies may be particularly volatile, and non-U.S. governments may intervene in the currency markets, causing a decline in value or liquidity in the Fund’s non-U.S. holdings whose value is tied to the affected non-U.S. currency.

DEPOSITARY RECEIPTS RISK. Ownership of ADRs and GDRs entails similar investment risks to direct ownership of non-U.S. securities traded outside the U.S., including liquidity, currency, political, information and other risks. In addition, any distributions paid to the holders of depositary receipts, whether ADRs or GDRs, are usually subject to a fee charged by the depositary.

18

Holders of depositary receipts may have limited voting rights pursuant to a deposit agreement between the underlying issuer and the depositary. In certain cases, the depositary will vote the securities deposited with it as directed by the underlying issuer’s board of directors. Furthermore, investment restrictions in certain countries may adversely impact the value of depositary receipts because such restrictions may limit the ability to convert securities into depositary receipts and vice versa. Such restrictions may cause securities of the underlying issuer to trade at a discount or premium to the market price of the depositary receipt. Moreover, if depositary receipts are converted into securities, the laws in certain countries may limit the ability of a non-resident to trade the securities and to reconvert the securities to depositary receipts.

DERIVATIVES RISK. The use of derivative instruments, including exchange-listed futures contracts on equity indexes, exchange-listed and OTC credit default index swaps and forward foreign currency exchange contracts, as well as derivatives that represent a component of a synthetic convertible security, involves risks and transaction costs which could leave the Fund in a worse position than if it had not used these instruments. Among the risks presented are market risk, credit risk, management risk and liquidity risk. Derivatives may entail investment exposures that are greater than their cost would suggest. As a result, a small investment in derivatives can result in losses that greatly exceed the original investment.

Derivatives can be highly volatile, illiquid and difficult to value, and there is the risk that changes in the value of a derivative held by the Fund will not correlate with the asset, index or rate underlying the derivative contract. In addition, when the Fund invests in certain derivative transactions, it is effectively leveraging its investments, which could result in exaggerated changes in the net asset value of the Fund’s shares and can result in losses that exceed the amount originally invested. The success of the Sub-Advisor's derivatives strategies will depend on its ability to assess and predict the impact of market or economic developments on the underlying asset, index or rate and the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions. Liquidity risk exists when a derivative instrument cannot be sold, closed out or replaced quickly at or very close to its fundamental value.

EQUITY SECURITIES RISK. The Fund may hold equity securities in its portfolio through direct investments in equity securities or upon conversion of a convertible security. Equity securities may decline significantly in price over short or extended periods of time, and such declines may occur in the equity market as a whole, or they may occur only in a particular country, company, industry or sector of the market.

HIGH YIELD SECURITIES RISK. The Fund’s investment high yield, high risk, domestic and foreign obligations, or “junk” debt, may entail increased credit risks and the risk that the value of Fund’s assets will decline, and may decline precipitously, with increases in interest rates.

Securities such as those included in the Fund are, under most circumstances, subject to greater market fluctuations and risk of loss of income and principal than are investments in lower-yielding, higher-rated securities, and their value may decline precipitously because of increases in interest rates. A slowdown in the economy, or a development adversely affecting an issuer’s creditworthiness, may result in the issuer being unable to maintain earnings or sell assets at the rate and at the prices, respectively, that are required to produce sufficient cash flow to meet its interest and principal requirements. For an issuer that has outstanding both senior commercial bank debt and subordinated high yield, high risk securities, an increase in interest rates will increase that issuer’s interest expense insofar as the interest rate on the bank debt is fluctuating. However, many leveraged issuers enter into interest rate protection agreements to fix or cap the interest rate on a large portion of their bank debt. This reduces exposure to increasing rates, but reduces the benefit to the issuer of declining rates. The Advisor cannot predict future economic policies or their consequences or, therefore, the course or extent of any similar market fluctuations in the future.

High yield debt may be issued by companies without long track records of sales and earnings, or by issuers that have questionable credit strength. High yield debt and comparable unrated debt securities: (a) will likely have some quality and protective characteristics that, in the judgment of the rating agency evaluating the instrument, are outweighed by large uncertainties or major risk exposures to adverse conditions; and (b) are predominantly speculative with respect to the issuer’s capacity to pay dividends or interest and repay principal in accordance with the terms of the obligation. Many lower-quality debt securities are subject to legal or contractual restrictions limiting the Fund's ability to resell the securities to the general public.

ILLIQUID AND RESTRICTED SECURITIES RISK. Investments in restricted securities could have the effect of increasing the amount of the Fund’s assets invested in illiquid securities if qualified institutional buyers are unwilling to purchase these securities. Illiquid and restricted securities may be difficult to dispose of at the price at which the Fund has valued the securities and at the times when the Fund believes it is desirable to do so. The market price of illiquid and restricted securities generally is more volatile than that of more liquid securities, which may adversely affect the price that the Fund recovers upon the sale

19

of such securities. Illiquid and restricted securities are also more difficult to value, especially in challenging markets. The Sub-Advisor’s judgment may play a greater role in the valuation process. Investment of the Fund’s assets in illiquid and restricted securities may restrict the Fund’s ability to take advantage of market opportunities. The risks associated with illiquid and restricted securities may be particularly acute in situations in which the Fund’s operations require cash and could result in the Fund incurring losses on the sale of illiquid or restricted securities. In order to dispose of an unregistered security, the Fund, where it has contractual rights to do so, may have to cause such security to be registered. A considerable period may elapse between the time the decision is made to sell the security and the time the security is registered, therefore enabling the Fund to sell it. Contractual restrictions on the resale of securities vary in length and scope and are generally the result of a negotiation between the issuer and acquiror of the securities. In either case, the Fund would bear market risks during that period.

INCOME RISK. The Fund’s income could decline due to falling market interest rates. This is because, in a falling interest rate environment, the Fund generally will have to invest the proceeds from sales of Fund shares, as well as the proceeds from maturing portfolio securities, or portfolio securities that have been called, in lower-yielding securities.

INDEX CREDIT DEFAULT SWAPS RISK. Index credit default swap transactions involve greater risks than if the Fund had invested in the reference obligations directly. In addition to general market risks, index credit default swaps are subject to liquidity risk, counterparty risk and credit risks. With respect to a reference obligation, a buyer will lose its investment and recover nothing should no event of default occur. For a seller, if an event of default were to occur, the value of the reference obligation received by the seller, coupled with the periodic payments previously received, may be less than the full notional value it pays to the buyer, resulting in a loss of value. When the Fund acts as a seller of an index credit default swap agreement, it is exposed to the risks of leverage since if an event of default occurs with respect to a reference obligation, the seller must pay the buyer the full notional value of the reference obligation.

INTEREST RATE RISK. The value of the Fund’s debt securities will fluctuate in value with changes in interest rates. In general, debt securities will increase in value when interest rates fall and decrease in value when interest rates rise. The Fund may be subject to a greater risk of rising interest rates than would normally be the case due to the current period of historically low rates and the effect of potential government fiscal policy initiatives and resulting market reaction to those initiatives.

Interest rate risk is generally lower for shorter term investments and higher for longer term investments. Duration is a common measure of interest rate risk. Duration measures a debt security’s expected life on a present value basis, taking into account the debt security’s yield, interest payments and final maturity. Duration is a reasonably accurate measure of a debt security’s price sensitivity to changes in interest rates. The longer the duration of a debt security, the greater the debt security’s price sensitivity is to changes in interest rates. Rising interest rates also may lengthen the duration of debt securities with call features, since exercise of the call because less likely as interest rates rise, which in turn will make the securities more sensitive to changes in interest rates and result in even steeper price declines in the event of further interest rate increases.

An increase in interest rates could also cause principal payments on a debt security to be repaid at a slower rate than expected. This risk is particularly prevalent for a callable security where an increase in interest rates could cause the issuer of that security to not redeem the security as anticipated on the call date, which could have the effect of lengthening that debt security’s expected maturity, in turn making that security more vulnerable to interest rate risk and reducing its market value.

When interest rates fall, the Fund may be required to reinvest the proceeds from the sale, redemption or early prepayment of a debt security at a lower interest rate.

MARKET RISK. Market risk is the risk that a particular security owned by the Fund or shares of the Fund in general may fall in value. Shares are subject to market fluctuations caused by such factors as economic, political, regulatory or market developments, changes in interest rates and perceived trends in securities prices.

NON-U.S. SECURITIES RISK. An investment in securities of non-U.S. issuers involves risks not associated with domestic issuers. Non-U.S. securities are subject to higher volatility than securities of domestic issuers due to possible adverse political, social or economic developments, restrictions on foreign investment or exchange of securities, lack of liquidity, currency exchange rates, excessive taxation, government seizure of assets, different legal or accounting standards, and less government supervision and regulation of exchanges in non-U.S. countries. The adoption of new governmental restrictions, including the possible imposition of withholding taxes on dividend income and the possible establishment of exchange controls or freezes on the convertibility of currency, might adversely affect an investment in non-U.S. securities. Investments in non-U.S. securities also may involve higher costs than investments in U.S. securities, including higher transaction and custody costs as well as the imposition of additional taxes by non-U.S. governments. Non-U.S. investments may also involve risks associated with less complete financial information about the issuers.

20

PREFERRED SECURITIES RISK. Preferred securities combine some of the characteristics of both common stocks and bonds. Preferred securities are typically subordinated to bonds and other debt instruments in a company’s capital structure in terms of priority to corporate income and therefore will be subject to greater credit risk than those debt instruments. Preferred securities are also subject to credit risk, interest rate risk and income risk, as well as the following.

•	Limited Voting Rights. Generally, holders of preferred securities (such as the Fund) have no voting rights with respect to the issuing company unless preferred dividends have been in arrears for a specified number of periods, at which time the preferred security holders may elect a number of directors to the issuer’s board. Generally, once the issuer pays all the arrearages, the preferred security holders no longer have voting rights.
•	Special Redemptions Rights. In certain circumstances, an issuer of preferred securities may redeem the securities prior to a specified date. For instance, for certain types of preferred securities, a redemption may be triggered by a change in federal income tax or securities laws. As with call provisions, a special redemption by the issuer may negatively impact the return of the security held by the Fund.
•	Deferral. Preferred securities may include provisions that permit the issuer, at its discretion, to defer distributions for a stated period without any adverse consequences to the issuer. If the Fund owns a preferred security that is deferring its distributions, the Fund may be required to report income for federal income tax purposes although it has not yet received such income in cash.
•	Subordination. Preferred securities are subordinated to bonds and other debt instruments in a company’s capital structure in terms of priority to corporate income and liquidation payments and therefore will be subject to greater credit risk than those debt instruments.
•	Liquidity. Preferred securities may be substantially less liquid than many other securities, such as common stocks or U.S. government securities.

21

in these currencies by the Fund. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.

FAILURE TO QUALIFY AS A REGULATED INVESTMENT COMPANY. If, in any year, the Fund fails to qualify as a regulated investment company under the applicable tax laws, the Fund would be taxed as an ordinary corporation. In such circumstances, the Fund could be required to recognize unrealized gains, pay substantial taxes and interest and make substantial distributions before requalifying as a regulated investment company that is accorded special tax treatment. If the Fund fails to qualify as a regulated investment company, distributions to the Fund’s shareholders generally would be eligible for the dividends received deduction in the case of corporate shareholders. See “Federal Tax Matters.”

INFLATION RISK. Inflation risk is the risk that the value of assets or income from investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. Certain securities in which the Fund invests may be particularly sensitive to rising interest rates, as the cost of capital rises and borrowing costs increase.

INTERNATIONAL CLOSED MARKET TRADING RISK. Because securities held by the Fund will trade on non-U.S. exchanges that are closed when the Fund's primary listing exchange is open, there are likely to be deviations between the current price of an underlying security and the last quoted price for the underlying security ( i.e. , the Fund’s quote from the closed foreign market), resulting in premiums or discounts to the Fund's net asset value that may be greater than those experienced by other ETFs. However, because shares can be created and redeemed in Creation Units at the Fund’s net asset value, it is not expected that large discounts or premiums to the net asset value of the Fund will be sustained over the long term (unlike shares of many closed-end funds, which frequently trade at appreciable discounts from, and sometimes at premiums to, their net asset values).

ISSUER SPECIFIC CHANGES RISK. The value of an individual security or particular type of security can be more volatile than the market as a whole and can perform differently from the value of the market as a whole.

LEGISLATION/LITIGATION RISK. From time to time, various legislative initiatives are proposed that may have a negative impact on certain securities in which the Fund invests. In addition, litigation regarding any of the securities owned by the Fund may negatively impact the value of a Fund’s shares. Such legislation or litigation may cause the Fund to lose value or may result in higher portfolio turnover if the Sub‑Advisor determines to sell such a holding.

VALUATION RISK. Unlike publicly traded common stock that trades on national exchanges, there is no central place or exchange for debt securities and preferred securities trading. Debt securities and preferred securities generally trade on an “over-the-counter” market which may be anywhere in the world where the buyer and seller can settle on a price. Due to the lack of centralized information and trading, the valuation of debt securities and preferred securities may carry more risk than that of common stock. Uncertainties in the conditions of the financial market, unreliable reference data, lack of transparency and inconsistency of valuation models and processes may lead to inaccurate asset pricing. In addition, other market participants may value securities differently than the Fund. As a result, the Fund may be subject to the risk that when a debt security or preferred security is sold in the market, the amount received by the Fund is less than the value of such debt security or preferred security carried on the Fund’s books.

Fund Organization

The Fund is a series of the Trust, an investment company registered under the 1940 Act. The Fund is treated as a separate fund with its own investment objective and policies. The Trust is organized as a Massachusetts business trust. The Trust's Board is responsible for the overall management and direction of the Trust. The Board elects the Trust’s officers and approves all significant agreements, including those with the investment advisor,Sub‑Advisor, custodian and fund administrative and accounting agent.

Management of the Fund

First Trust Advisors L.P., 120 East Liberty Drive, Wheaton, Illinois 60187, is the investment advisor to the Fund. In this capacity, First Trust is responsible for overseeing the Sub‑Advisor in the investment of the Fund’s assets, managing the Fund’s business affairs and providing certain clerical, bookkeeping and other administrative services.

First Trust is a limited partnership with one limited partner, Grace Partners of DuPage L.P., and one general partner, The Charger Corporation. Grace Partners of DuPage L.P. is a limited partnership with one general partner, The Charger Corporation, and

22

a number of limited partners. The Charger Corporation is an Illinois corporation controlled by James A. Bowen, the Chief Executive Officer of First Trust. First Trust discharges its responsibilities subject to the policies of the Board.

First Trust serves as advisor or sub-advisor for seven mutual fund portfolios, 10 exchange-traded funds consisting of 130 series and 16 closed-end funds. It is also the portfolio supervisor of certain unit investment trusts sponsored by First Trust Portfolios L.P. ( “FTP” ), an affiliate of First Trust, 120 East Liberty Drive, Wheaton, Illinois 60187. FTP specializes in the underwriting, trading and distribution of unit investment trusts and other securities. FTP is the principal underwriter of the shares of the Fund.

The Fund and First Trust have retained SSI, 9440 Santa Monica Blvd, 8th Floor, Beverly Hills, California 90210, to serve as investment sub-advisor. In this capacity, SSI is responsible for the selection and ongoing monitoring of the securities in the Fund’s investment portfolio. SSI was formed in 1973 and serves as investment advisor to investment portfolios with approximately $1.6 billion in assets which it managed as of December 31, 2017. SSI provides investment advisory services to pension and profit sharing plans, corporations, foundations and endowments, Taft-Hartley plans, family offices, insurance companies, public funds, high-net worth individuals, private investment vehicles, religious organizations and mutual funds.

SSI is an investment management firm specializing in alternative investment solutions utilizing convertible assets, equity securities and hedging strategies. The members of its portfolio management team for the Fund are: George M. Douglas, CFA; Ravi Malik, CFA; Michael J. Opre, CFA; Florian Eitner, CFA; and Ethan Ganz, who share responsibilities for the day-to-day management of the Fund’s investment portfolio.

•	Mr. Douglas, CFA, has been a Principal and the Chief Investment Officer of SSI Investment Management Inc. since 1994 and oversees SSI’s qualitative and quantitative research processes. Mr. Douglas has 40 years of experience in quantitative equity research and portfolio management. Prior to joining SSI, Mr. Douglas was Director of Quantitative Equity Investments and Portfolio Manager for CS First Boston Asset Management from 1992 to 1994. From 1990 to 1992, Mr. Douglas was Chief Investment Officer for Structured Asset Management, which was part of Templeton International, and from 1980 to 1990, Mr. Douglas was Senior Vice President and Director of Research for Drexel Burnham Lambert. Mr. Douglas received an MBA in Finance in 1978, an MS in Statistics in 1977 and a BS in Mathematics in 1976 from the University of Wisconsin-Madison.
•	Mr. Malik, CFA, is a Principal and Portfolio Manager overseeing the daily management of the Convertible Investment portfolios as well as providing equity and credit research in the Technology and Emerging Markets Sectors. Mr. Malik has 19 years of experience as a Portfolio Manager and 3 years as an Analyst on SSI’s Convertible Investment Team and the Froley Revy Convertible Team (acquired by SSI in 2009). Mr. Malik collaborates with SSI’s CIO in analyzing Global and Macro environments and formulates strategy according to client mandates. Prior to joining SSI, Mr. Malik spent 10 years in the Indian Administrative Service (IAS), India’s highest level “Think Tank”. He also served as Finance Commissioner to the Andaman Islands. Mr. Malik received an MBA in Finance from the Anderson Graduate School of Management, University of California, Los Angeles as well as a B.A. in Mathematics and Economics from Punjab University.
•	Mr. Opre, CFA, is a Portfolio Manager overseeing the daily management of the Convertible Investment portfolios as well as providing equity and credit research in the Finance, Energy and Materials Sectors. Mr. Opre has 29 years of industry experience, including 16 years as a Portfolio Manager of the SSI Convertible Investment Team and the Froley Revy Convertible Team (acquired by SSI in 2009). Mr. Opre’s prior experience includes serving as a Senior Investment Manager at Wells Fargo and as a Research Analyst with Pacific Strategic Fund Group, Inc. specializing in fundamental analysis and risk arbitrage. He holds an MBA in Finance from the Anderson Graduate School of Management, University of California, Los Angeles as well as a BA from the University of California, Los Angeles.
•	Mr. Eitner, CFA, is a Portfolio Manager overseeing the daily management of the Convertible Investment portfolios as well as providing equity and credit research in the Healthcare, Industrials and Transportation Sectors. Mr. Eitner has 20 years of industry experience, including 14 years as an Analyst and Portfolio Manager of SSI’s Convertible Investment Team and the Froley Revy Convertible Team (acquired by SSI in 2009). Prior to joining SSI, Mr. Eitner was an Associate in the Leveraged Finance Group at Lehman Brothers Europe. Previously, he was a member of CTC, LLC options trading group at the Chicago Mercantile Exchange. Mr. Eitner has an MBA in Finance from the Anderson Graduate School of Management, University of California, Los Angeles, where he was a Student Investment Fund Fellow. He also holds a BA in Economics from Northwestern University, Chicago.
•	Mr. Ganz is a Portfolio Manager overseeing the daily management of the Convertible Investment portfolios. He is responsible for coordinating the credit ratings process for all portfolio positions and candidates, as well

23

as for quantitative and analytical reports on portfolio positions and the convertible universe. Prior to August, 2015, he was a Senior Analyst. Mr. Ganz has 13 years of experience with SSI and the Froley Revy Investment Team (acquired by SSI in 2009). He holds a BA from Pomona College.

In managing the Fund’s investment portfolio, the portfolio managers work together with Lily Yu, a convertible securities trader.

•

Mrs. Yu is the Head Convertible Investment Trader responsible for trading all Convertible Investment portfolios. She maintains and develops new outright institutional trading relationships. Mrs. Yu has 27 years of experience in the finance industry and 23 years of experience in convertible trading with SSI and the Froley Revy Investment Team (acquired by SSI in 2009). Mrs. Yu holds a B.A. from the University of California, Los Angeles.

For additional information concerning First Trust and the Sub‑Advisor, including a description of the services provided to the Fund, see the Fund’s SAI. Additional information about the portfolio managers’ compensation, other accounts managed by the portfolio managers and the portfolio managers’ ownership of shares in the Fund is provided in the SAI.

Management Fee

Pursuant to the Investment Management Agreement, First Trust is paid an annual management fee of 0.95% of the Fund’s average daily net assets. First Trust supervises SSI and its management of the investment of the Fund’s assets and pays SSI for its services as the Fund’s Sub-Advisor. First Trust is responsible for the Fund’s expenses, including the cost of transfer agency, custody, fund administration, legal, audit and other services, but excluding fee payments under the Investment Management Agreement, interest, taxes, acquired fund fees and expenses, brokerage commissions and other expenses connected with the execution of portfolio transactions, distribution and service fees pursuant to a 12b-1 plan, if any, and extraordinary expenses.

A discussion regarding the Board’s approval of the continuation of the Investment Management Agreement and Sub-Advisory Agreement for the Fund is available in the Fund’s Annual Report to shareholders for the fiscal year ended October 31, 2017.

How to Buy and Sell Shares

Most investors will buy and sell shares of the Fund in secondary market transactions through brokers. Shares of the Fund are listed for trading on the secondary market on Nasdaq. Shares can be bought and sold throughout the trading day like other publicly traded shares. There is no minimum investment when buying shares on Nasdaq. Although shares are generally purchased and sold in “round lots” of 100 shares, brokerage firms typically permit investors to purchase or sell shares in smaller “odd lots,” at no per-share price differential. When buying or selling shares through a broker, investors should expect to incur customary brokerage commissions, investors may receive less than the net asset value of the shares because shares are bought and sold at market prices rather than net asset value, and investors may pay some or all of the spread between the bid and the offer price in the secondary market on each leg of a round trip (purchase and sale) transaction. Share prices are reported in dollars and cents per share.

For purposes of the 1940 Act, the Fund is treated as a registered investment company, and, absent an available exemption or exemptive relief, the acquisition of shares by other registered investment companies and companies relying on Sections 3(c)(1) or 3(c)(7) of the 1940 Act is subject to the restrictions of Section 12(d)(1) of the 1940 Act. The Trust, on behalf of the Fund, has received an exemptive order from the Securities and Exchange Commission that permits certain registered investment companies to invest in the Fund beyond the limits set forth in Section 12(d)(1), subject to certain terms and conditions, including that any such investment companies enter into an agreement with the Fund regarding the terms of any investment. In addition, the Fund may invest in the securities of BDCs in excess of the limits imposed under the 1940 Act pursuant to an exemptive order obtained by the Trust and the Advisor from the Securities and Exchange Commission.

Book Entry

Shares are held in book-entry form, which means that no share certificates are issued. The Depository Trust Company (“ DTC ”) or its nominee is the record owner of all outstanding shares of the Fund and is recognized as the owner of all shares for all purposes.

Investors owning shares are beneficial owners as shown on the records of DTC or its participants. DTC serves as the securities depository for all shares. Participants in DTC include securities brokers and dealers, banks, trust companies, clearing corporations and other institutions that directly or indirectly maintain a custodial relationship with DTC. As a beneficial owner of shares, you are not entitled to receive physical delivery of share certificates or to have shares registered in your name, and you are not considered a registered owner of shares. Therefore, to exercise any right as an owner of shares, you must rely

24

upon the procedures of DTC and its participants. These procedures are the same as those that apply to any other stocks that you hold in book-entry or “street name” form.

Share Trading Prices

The trading prices of shares of the Fund on Nasdaq may differ from the Fund’s daily net asset value and can be affected by market forces of supply and demand, economic conditions and other factors.

Information regarding the intra-day value of the shares of the Fund, also referred to as the “indicative optimized portfolio value” (“ IOPV ”), is disseminated every 15 seconds throughout the Fund’s trading day by the national securities exchange on which the shares are listed or by market data vendors or other information providers. The IOPV should not be viewed as a “real-time” update of the net asset value per share of the Fund because the IOPV may not be calculated in the same manner as the net asset value, which is computed once a day, generally at the end of the business day. The price of a non-U.S. security that is primarily traded on a non-U.S. exchange will be updated, using the last sale price, every 15 seconds throughout the trading day, provided, that, upon the closing of such non-U.S. exchange, the closing price of the security, after being converted to U.S. dollars, will be used. This will likely cause the IOPV to deviate significantly from the true market value of the portfolio. Furthermore, in calculating the IOPV of the Fund’s shares, exchange rates may be used throughout the day (9:00 a.m. to 4:15 p.m., Eastern time) that may differ from those used to calculate the net asset value per share of the Fund and consequently may result in differences between the net asset value and the IOPV. The Fund is not involved in, or responsible for, the calculation or dissemination of the IOPV of shares of the Fund and the Fund does not make any warranty as to its accuracy.

Frequent Purchases and Redemptions of the Fund’s Shares

The Fund imposes no restrictions on the frequency of purchases and redemptions (“ market timing ”). In determining not to approve a written, established policy, the Board evaluated the risks of market timing activities by the Fund’s shareholders. The Board considered that the Fund’s shares can only be purchased and redeemed directly from the Fund in Creation Units by broker-dealers and large institutional investors that have entered into participation agreements ( i.e. , authorized participants (“ APs ”)) and that the vast majority of trading in the Fund’s shares occurs on the secondary market. Because the secondary market trades do not involve the Fund directly, it is unlikely those trades would cause many of the harmful effects of market timing, including dilution, disruption of portfolio management, increases in the Fund’s trading costs and the realization of capital gains. As the Fund may effect the purchase or redemption of Creation Units in exchange wholly or partially for cash, the Board noted that such trades could result in dilution to the Fund and increased transaction costs, which could negatively impact the Fund’s ability to achieve its investment objective. However, the Board noted that direct trading by APs is critical to ensuring that the shares trade at or close to net asset value. In addition, the Fund imposes fixed and variable transaction fees on purchases and redemptions of Creation Units to cover the custodial and other costs incurred by the Fund in effecting trades. Finally, the Advisor monitors purchase and redemption orders from APs for patterns of abusive trading. The Fund reserves the right to reject purchase and redemption orders from APs that the Advisor has determined may be disruptive to the management of the Fund, or otherwise not in the Fund’s best interests.

Dividends, Distributions and Taxes

Dividends from net investment income, if any, are declared and paid monthly by the Fund. The Fund distributes its net realized capital gains, if any, to shareholders at least annually.

Distributions in cash may be reinvested automatically in additional whole shares only if the broker through whom you purchased shares makes such option available. Such shares will generally be reinvested by the broker based upon the market price of those shares and investors may be subject to customary brokerage commissions charged by the broker.

Federal Tax Matters

This section summarizes some of the main U.S. federal income tax consequences of owning shares of the Fund. This section is current as of the date of this prospectus. Tax laws and interpretations change frequently, and these summaries do not describe all of the tax consequences to all taxpayers. For example, these summaries generally do not describe your situation if you are a corporation, a non-U.S. person, a broker-dealer or other investor with special circumstances. In addition, this section does not describe your state, local or non-U.S. tax consequences.

This federal income tax summary is based in part on the advice of counsel to the Fund. The Internal Revenue Service could disagree with any conclusions set forth in this section. In addition, counsel to the Fund was not asked to review, and has not

25

reached a conclusion with respect to, the federal income tax treatment of the assets to be included in the Fund. This may not be sufficient for you to use for the purpose of avoiding penalties under federal tax law.

As with any investment, you should seek advice based on your individual circumstances from your own tax advisor.

Fund Status

The Fund intends to continue to qualify as a “regulated investment company” under the federal tax laws. If the Fund qualifies as a regulated investment company and distributes its income as required by the tax law, the Fund generally will not pay federal income taxes.

Distributions

The Fund’s distributions are generally taxable. After the end of each year, you will receive a tax statement that separates the distributions of the Fund into two categories: ordinary income distributions and capital gain dividends. Ordinary income distributions are generally taxed at your ordinary tax rate, however, as further discussed below, certain ordinary income distributions received from the Fund may be taxed at the capital gains tax rates. Generally, you will treat all capital gain dividends as long-term capital gains regardless of how long you have owned your shares.

To determine your actual tax liability for your capital gain dividends, you must calculate your total net capital gain or loss for the tax year after considering all of your other taxable transactions, as described below. In addition, the Fund may make distributions that represent a return of capital for tax purposes and thus will generally not be taxable to you; however, such distributions may reduce your tax basis in your shares, which could result in you having to pay higher taxes in the future when shares are sold, even if you sell the shares at a loss from your original investment. The tax status of your distributions from the Fund is not affected by whether you reinvest your distributions in additional shares or receive them in cash. The income from the Fund that you must take into account for federal income tax purposes is not reduced by amounts used to pay a deferred sales fee, if any. The tax laws may require you to treat distributions made to you in January as if you had received them on December 31 of the previous year.

Income from the Fund may also be subject to a 3.8% “Medicare tax.” This tax generally applies to your net investment income if your adjusted gross income exceeds certain threshold amounts, which are $250,000 in the case of married couples filing joint returns and $200,000 in the case of single individuals.

Dividends Received Deduction

A corporation that owns shares generally will not be entitled to the dividends received deduction with respect to many dividends received from the Fund because the dividends received deduction is generally not available for distributions from regulated investment companies. However, certain ordinary income dividends on shares that are attributable to qualifying dividends received by the Fund from certain corporations may be reported by the Fund as being eligible for the dividends received deduction.

Capital Gains and Losses and Certain Ordinary Income Dividends

If you are an individual, the maximum marginal stated federal tax rate for net capital gain is generally 20% (15% or 0% for taxpayers with taxable income below certain thresholds). Some capital gain dividends may be taxed at a higher maximum stated tax rate. Capital gains may also be subject to the Medicare tax described above.

Net capital gain equals net long-term capital gain minus net short-term capital loss for the taxable year. Capital gain or loss is long-term if the holding period for the asset is more than one year and is short-term if the holding period for the asset is one year or less. You must exclude the date you purchase your shares to determine your holding period. However, if you receive a capital gain dividend from the Fund and sell your share at a loss after holding it for six months or less, the loss will be recharacterized as long-term capital loss to the extent of the capital gain dividend received. The tax rates for capital gains realized from assets held for one year or less are generally the same as for ordinary income. The Internal Revenue Code of 1986, as amended, treats certain capital gains as ordinary income in special situations.

Ordinary income dividends received by an individual shareholder from a regulated investment company such as the Fund are generally taxed at the same rates that apply to net capital gain (as discussed above), provided certain holding period requirements are satisfied and provided the dividends are attributable to qualifying dividends received by the Fund itself. The Fund will provide notice to its shareholders of the amount of any distribution which may be taken into account as a dividend which is eligible for the capital gains tax rates.

26

Sale of Shares

If you sell or redeem your shares, you will generally recognize a taxable gain or loss. To determine the amount of this gain or loss, you must subtract your tax basis in your shares from the amount you receive in the transaction. Your tax basis in your shares is generally equal to the cost of your shares, generally including sales charges. In some cases, however, you may have to adjust your tax basis after you purchase your shares.

Taxes on Purchase and Redemption of Creation Units

If you exchange securities for Creation Units you will generally recognize a gain or a loss. The gain or loss will be equal to the difference between the market value of the Creation Units at the time and your aggregate basis in the securities surrendered and the cash component paid. If you exchange Creation Units for securities, you will generally recognize a gain or loss equal to the difference between your basis in the Creation Units and the aggregate market value of the securities received and the cash redemption amount. The Internal Revenue Service, however, may assert that a loss realized upon an exchange of securities for Creation Units or Creation Units for securities cannot be deducted currently under the rules governing “wash sales,” or on the basis that there has been no significant change in economic position.

Treatment of Fund Expenses

Expenses incurred and deducted by the Fund will generally not be treated as income taxable to you. In some cases, however, you may be required to treat your portion of these Fund expenses as income. You may not be able to deduct some or all of these expenses.

Non-U.S. Tax Credit

Because the Fund invests in non-U.S. securities, the tax statement that you receive may include an item showing non-U.S. taxes the Fund paid to other countries. In this case, dividends taxed to you will include your share of the taxes the Fund paid to other countries. You may be able to deduct or receive a tax credit for your share of these taxes.

Non-U.S. Investors

If you are a non-U.S. investor ( i.e. , an investor other than a U.S. citizen or resident or a U.S. corporation, partnership, estate or trust), you should be aware that, generally, subject to applicable tax treaties, distributions from the Fund will be characterized as dividends for federal income tax purposes (other than dividends which the Fund properly reports as capital gain dividends) and will be subject to U.S. federal income taxes, including withholding taxes, subject to certain exceptions described below. However, distributions received by a non-U.S. investor from the Fund that are properly reported by the Fund as capital gain dividends may not be subject to U.S. federal income taxes, including withholding taxes, provided that the Fund makes certain elections and certain other conditions are met. Distributions from a Fund that are properly reported by the Fund as an interest-related dividend attributable to certain interest income received by the Fund or as a short-term capital gain dividend attributable to certain net short-term capital gain income received by the Fund may not be subject to U.S. federal income taxes, including withholding taxes when received by certain non-U.S. investors, provided that the Fund makes certain elections and certain other conditions are met.

Distributions may be subject to a U.S. withholding tax of 30% in the case of distributions to (i) certain non-U.S. financial institutions that have not entered into an agreement with the U.S. Treasury to collect and disclose certain information and are not resident in a jurisdiction that has entered into such an agreement with the U.S. Treasury and (ii) certain other non-U.S. entities that do not provide certain certifications and information about the entity’s U.S. owners. Dispositions of shares by such persons may be subject to such withholding after December 31, 2018.

Investments in Certain Non-U.S. Corporations

If the Fund holds an equity interest in any passive foreign investment companies (“ PFICs ”), which are generally certain non-U.S. corporations that receive at least 75% of their annual gross income from passive sources (such as interest, dividends, certain rents and royalties or capital gains) or that hold at least 50% of their assets in investments producing such passive income, the Fund could be subject to U.S. federal income tax and additional interest charges on gains and certain distributions with respect to those equity interests, even if all the income or gain is timely distributed to its shareholders. The Fund will not be able to pass through to its shareholders any credit or deduction for such taxes. The Fund may be able to make an election that could ameliorate these adverse tax consequences. In this case, the Fund would recognize as ordinary income any increase in the value of such PFIC shares, and as ordinary loss any decrease in such value to the extent it did not exceed prior increases included in income. Under this election, the Fund might be required to recognize in a year income in excess of its distributions from PFICs and its proceeds from dispositions of PFIC stock during that year, and such income would nevertheless be subject

27

to the distribution requirement and would be taken into account for purposes of the 4% excise tax. Dividends paid by PFICs are not treated as qualified dividend income.

Distribution Plan

FTP serves as the distributor of Creation Units for the Fund on an agency basis. FTP does not maintain a secondary market in shares.

The Board has adopted a Distribution and Service Plan pursuant to Rule 12b-1 under the 1940 Act. In accordance with the Rule 12b-1 plan, the Fund is authorized to pay an amount up to 0.25% of its average daily net assets each year to reimburse FTP for amounts expended to finance activities primarily intended to result in the sale of Creation Units or the provision of investor services. FTP may also use this amount to compensate securities dealers or other persons that are APs for providing distribution assistance, including broker-dealer and shareholder support and educational and promotional services.

The Fund does not currently pay 12b-1 fees, and pursuant to a contractual arrangement, the Fund will not pay 12b-1 fees any time before March 31, 2019. However, in the event 12b-1 fees are charged in the future, because these fees are paid out of the Fund's assets, over time these fees will increase the cost of your investment and may cost you more than certain other types of sales charges.

Net Asset Value

The Fund’s net asset value is determined as of the close of trading (normally 4:00 p.m., Eastern time) on the New York Stock Exchange (the “ NYSE ”) on each day the NYSE is open for trading. If the NYSE closes early on a valuation day, the Fund’s net asset value will be determined as of that time. Net asset value per share is calculated for the Fund by taking the market price of the Fund’s total assets, including interest or dividends accrued but not yet collected, less all liabilities, and dividing such amount by the total number of shares outstanding. The result, rounded to the nearest cent, is the net asset value per share. All valuations are subject to review by the Fund’s Board or its delegate.

The Fund’s investments are valued daily at market or, in the absence of market value with respect to any investments, at fair value. Market value prices represent last sale or official closing prices from a national or foreign exchange ( i.e. , a regulated market) and are primarily obtained from third party pricing services (“ Pricing Services ”). Fair value prices represent any prices not considered market value prices and are either obtained from a Pricing Service or determined by the Advisor’s pricing committee (the “ Pricing Committee ”), in accordance with valuation procedures (which may be revised from time to time) adopted by the Trust’s Board of Trustees, and in accordance with provisions of the 1940 Act. As a general principle, the current “fair value” of a security would appear to be the amount which the owner might reasonably expect to receive for the security upon its current sale. Valuing the Fund’s assets using fair value pricing can result in using prices for those assets (particularly assets that trade in foreign markets) that may differ from current market valuations.

Certain securities in which the Fund may invest are not listed on any securities exchange or board of trade. Such securities are typically bought and sold by institutional investors in individually negotiated private transactions that function in many respects like an over-the-counter secondary market, although typically no formal market makers exist. Certain securities, particularly debt securities, have few or no trades, or trade infrequently, and information regarding a specific security may not be widely available or may be incomplete. Accordingly, determinations of the fair value of debt securities may be based on infrequent and dated information. Because there is less reliable, objective data available, elements of judgment may play a greater role in valuation of debt securities than for other types of securities. Typically, Convertible Securities, short-term debt instruments and OTC index credit default swaps are fair valued using information provided by a Pricing Service or obtained from broker-dealer quotations. Short-term debt instruments having a remaining maturity of 60 days or less when purchased are typically valued at cost adjusted for amortization of premiums and accretion of discounts, provided that the Pricing Committee has determined that the use of amortized cost is an appropriate reflection of fair value given market and issuer-specific conditions existing at the time of the determination.

Equity securities and ETNs listed on any exchange other than Nasdaq and the London Stock Exchange Alternative Investment Market (“ AIM ”) are typically valued at the last sale price on the exchange on which they are principally traded. Such securities listed on Nasdaq or the AIM are typically valued at the official closing price on the business day as of which such value is being determined. If there has been no sale on such day, or no official closing price in the case of securities traded on Nasdaq or the AIM, such securities are typically valued using fair value pricing. Such securities traded on more than one securities exchange are valued at the last sale price or official closing price, as applicable, on the business day as of which such value is being determined at the close of the exchange representing the principal market for such securities.

28

Exchange-listed Convertible Securities (if any), exchange-listed equity index futures contracts and exchange-listed index credit default swaps are typically valued at the closing price in the market where such instruments are principally traded. If no official closing price is available, such instruments are fair valued at the mean of their most recent bid and asked price on the exchange on which they are principally traded, if available, and otherwise at their closing bid price.

Forward foreign currency exchange contracts are typically fair valued at the current day’s interpolated foreign exchange rate, as calculated using the current day’s spot rate, and the thirty, sixty, ninety and one-hundred-eighty day forward rates provided by a Pricing Service or by certain independent dealers in such contracts.

Because foreign securities exchanges may be open on different days than the days during which an investor may purchase or sell shares of the Fund, the value of the Fund’s securities may change on days when investors are not able to purchase or sell shares of the Fund. Assets denominated in foreign currencies are translated into U.S. dollars at the exchange rate of such currencies against the U.S. dollar as provided by a Pricing Service. The value of assets denominated in foreign currencies is converted into U.S. dollars at the exchange rates in effect at the time of valuation.

Fund Service Providers

Brown Brothers Harriman & Co., 50 Post Office Square, Boston, Massachusetts 02110, acts as the administrator, accounting agent, custodian and transfer agent for the Fund. Chapman and Cutler LLP, 111 West Monroe Street, Chicago, Illinois 60603, serves as legal counsel to the Fund. First Trust serves as the fund reporting agent for the Fund.

Premium/Discount Information

The table that follows presents information about the differences between the Fund’s daily market price on Nasdaq and its net asset value. The “Market Price” of the Fund generally is determined using the midpoint between the highest bid and lowest offer on Nasdaq, as of the time the Fund’s net asset value is calculated. The Fund’s Market Price may be at, above, or below its net asset value. The net asset value of the Fund will fluctuate with changes in the market value of its portfolio holdings. The Market Price of the Fund will fluctuate in accordance with changes in its net asset value, as well as market supply and demand.

Premiums or discounts are the differences (generally expressed as a percentage) between the net asset value and Market Price of the Fund on a given day, generally at the time net asset value is calculated. A premium is the amount that the Fund is trading above the reported net asset value. A discount is the amount that the Fund is trading below the reported net asset value.

The following information shows the frequency distribution of premiums and discounts of the daily bid/ask price of the Fund against the Fund’s net asset value. The information shown for the Fund is for the period indicated. Shareholders may pay more than net asset value when they buy Fund shares and receive less than net asset value when they sell those shares because shares are bought and sold at current market price. All data presented here represents past performance, which cannot be used to predict future results. Information about the premiums and discounts at which the Fund’s shares have traded is available on the Fund’s website at www.ftportfolios.com.

First Trust SSI Strategic Convertible Securities ETF (FCVT)
Bid/Ask Midpoint vs. Net Asset Value

Number of Days Bid/Ask Midpoint At/Above Net Asset Value

	0.00% – 0.49%	0.50% – 0.99%	1.00% – 1.99%	>=2.00%
12 Months Ended 12/31/2017	162	39	2	1

Number of Days Bid/Ask Midpoint Below Net Asset Value

	0.00% – 0.49%	0.50% – 0.99%	1.00% – 1.99%	>=2.00%
12 Months Ended 12/31/2017	46	1	0	0

29

Total Return Information

The table below compares the total return of the Fund to a broad-based securities market index. The information presented for the Fund is for the period indicated.

“Average annual total returns” represent the average annual change in the value of an investment over the period indicated. “Cumulative total returns” represent the total change in value of an investment over the period indicated. The net asset value per share of the Fund is the value of one share of the Fund and is computed by dividing the value of all assets of the Fund (including accrued interest and dividends), less liabilities (including accrued expenses and dividends declared but unpaid), by the total number of outstanding shares. The net asset value return is based on the net asset value per share of the Fund, and the market return is based on the market price per share of the Fund. The price used to calculate market return ( “Market Price” ) generally is determined by using the midpoint between the highest bid and the lowest offer on Nasdaq as of the time that the Fund's net asset value is calculated. Since the shares of the Fund typically do not trade in the secondary market until several days after the Fund's inception, for the period from inception to the first day of secondary market trading in shares of the Fund, the net asset value of the Fund is used as a proxy for the secondary market trading price to calculate market returns. Market and net asset value returns assume that all distributions have been reinvested in the Fund at Market Price and net asset value, respectively. An index is a statistical composite that tracks a specified financial market or sector. Unlike the Fund, an index does not actually hold a portfolio of securities and therefore does not incur the expenses incurred by the Fund. These expenses negatively impact the performance of the Fund. Also, market returns do not include brokerage commissions that may be payable on secondary market transactions. If brokerage commissions were included, market returns would be lower. The total returns reflect the reinvestment of dividends on securities in the index. The returns shown in the table below do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or the redemption or sale of shares of the Fund. The investment return and principal value of shares of the Fund will vary with changes in market conditions. Shares of the Fund may be worth more or less than their original cost when they are redeemed or sold in the market. The Fund's past performance is no guarantee of future results.

First Trust SSI Strategic Convertible Securities ETF (FCVT)
Total Returns as of October 31, 2017

		Average Annual		Cumulative
	1 Year	Inception (11/3/2015)		Inception (11/3/2015)
Fund Performance
Net Asset Value	17.29%	9.79%		20.44%
Market Price	17.02%	9.88%		20.63%
Index Performance
ICE BofAML All US Convertibles Index (1)	18.13%	10.01%		20.93%

(1)	Effective October 22, 2017, the index name changed from BofA Merill Lynch All US Convertibles Index to ICE BofAML All US Convertibles Index.

30

Financial Highlights

The financial highlights table is intended to help you understand the Fund's financial performance for the periods shown. Certain information reflects financial results for a single share of the Fund. The total return represents the rate that an investor would have earned (or lost) on an investment in the Fund (assuming reinvestment of all dividends and distributions). The information for the periods indicated has been derived from financial statements audited by Deloitte & Touche LLP, whose report, along with the Fund's financial statements, is included in the Fund's Annual Report to Shareholders dated October 31, 2017 and is incorporated by reference in the Fund's SAI, which is available upon request.

(a)	Inception date is consistent with the commencement of investment operations and is the date the initial creation units were established.

(b)

Total return is calculated assuming an initial investment made at the net asset value at the beginning of the period, reinvestment of all distributions at net asset value during the period, and redemption at net asset value on the last day of the period. The returns presented do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or the redemption or sale of Fund shares. Total return is calculated for the time period presented and is not annualized for periods of less than a year.

(c)	Annualized.
(d)	Portfolio turnover is calculated for the time period presented and is not annualized for periods of less than a year and does not include securities received or delivered from processing creations or redemptions and in-kind transactions.

31

Other Information

Continuous Offering

The Fund issues, on a continuous offering basis, its shares in one or more groups of a fixed number of Fund shares (each such group of such specified number of individual Fund shares, a “Creation Unit Aggregation” ). The method by which Creation Unit Aggregations of Fund shares are created and traded may raise certain issues under applicable securities laws. Because new Creation Unit Aggregations of shares are issued and sold by the Fund on an ongoing basis, a “distribution,” as such term is used in the Securities Act, may occur at any point. Broker-dealers and other persons are cautioned that some activities on their part may, depending on the circumstances, result in their being deemed participants in a distribution in a manner which could render them statutory underwriters and subject them to the prospectus delivery requirement and liability provisions of the Securities Act.

For example, a broker-dealer firm or its client may be deemed a statutory underwriter if it takes Creation Unit Aggregations after placing an order with FTP, breaks them down into constituent shares and sells such shares directly to customers, or if it chooses to couple the creation of a supply of new shares with an active selling effort involving solicitation of secondary market demand for shares. A determination of whether one is an underwriter for purposes of the Securities Act must take into account all the facts and circumstances pertaining to the activities of the broker-dealer or its client in the particular case, and the examples mentioned above should not be considered a complete description of all the activities that could lead to a characterization as an underwriter.

Broker-dealer firms should also note that dealers who are not “underwriters” but are effecting transactions in shares, whether or not participating in the distribution of shares, are generally required to deliver a prospectus. This is because the prospectus delivery exemption in Section 4(a)(3) of the Securities Act is not available in respect of such transactions as a result of Section 24(d) of the 1940 Act. As a result, broker-dealer firms should note that dealers who are not underwriters but are participating in a distribution (as contrasted with ordinary secondary market transactions) and thus dealing with the shares that are part of an overallotment within the meaning of Section 4(a)(3)(C) of the Securities Act would be unable to take advantage of the prospectus delivery exemption provided by Section 4(a)(3) of the Securities Act. Firms that incur a prospectus delivery obligation with respect to shares are reminded that, under Rule 153 of the Securities Act ( “Rule 153” ), a prospectus delivery obligation under Section 5(b)(2) of the Securities Act owed to a broker-dealer in connection with a sale on Nasdaq is satisfied by the fact that the prospectus is available from Nasdaq upon request. The prospectus delivery mechanism provided in Rule 153 is available with respect to transactions on a national securities exchange, a trading facility or an alternative trading system.

32

      

[THIS PAGE INTENTIONALLY LEFT BLANK.]

First Trust SSI Strategic Convertible Securities ETF

For More Information

For more detailed information on the Fund, several additional sources of information are available to you. The SAI, incorporated by reference into this prospectus, contains detailed information on the Fund's policies and operation. Additional information about the Fund's investments is available in the annual and semi-annual reports to shareholders. In the Fund's annual report, you will find a discussion of the market conditions and investment strategies that significantly impacted the Fund's performance during the last fiscal year. The Fund's most recent SAI, annual and semi-annual reports and certain other information are available free of charge by calling the Fund at (800) 621-1675, on the Fund's website at www.ftportfolios.com or through your financial advisor. Shareholders may call the toll-free number above with any inquiries.

You may obtain this and other information regarding the Fund, including the SAI and the Codes of Ethics adopted by First Trust, FTP and the Trust, directly from the Securities and Exchange Commission (the “SEC” ). Information on the SEC’s website is free of charge. Visit the SEC’s online EDGAR database at www.sec.gov or in person at the SEC’s Public Reference Room in Washington, D.C., or call the SEC at (202) 551-8090 for information on the Public Reference Room. You may also request information regarding the Fund by sending a request (along with a duplication fee) to the SEC’s Public Reference Section, 100 F Street, N.E., Washington, D.C. 20549-1520 or by sending an electronic request to publicinfo@sec.gov.

First Trust Advisors L.P.
120 East Liberty Drive, Suite 400
Wheaton, Illinois 60187
(800) 621-1675
www.ftportfolios.com

SEC File #: 333-174332

811-22559

Prospectus

First Trust Strategic Income ETF

Ticker Symbol:	FDIV
Exchange:	Nasdaq

First Trust Strategic Income ETF (the “Fund” ) lists and principally trades its shares on The Nasdaq Stock Market LLC ( “Nasdaq” or the “Exchange” ). Market prices may differ to some degree from the net asset value of the shares. Unlike mutual funds, the Fund issues and redeems shares at net asset value, only in large specified blocks each consisting of 50,000 shares (each such block of shares called a “Creation Unit,” and collectively, the “Creation Units” ). The Fund’s Creation Units are generally issued and redeemed in-kind for securities in which the Fund invests and/or cash, and only to and from broker-dealers and large institutional investors that have entered into participation agreements.

The Fund is a series of First Trust Exchange-Traded Fund IV (the “Trust” ) and an actively managed exchange-traded fund organized as a separate series of a registered management investment company.

Except when aggregated in Creation Units, the shares are not redeemable securities of the Fund.

The Securities and Exchange Commission has not approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

Table of Contents

Summary Information	3
Additional Information on the Fund's Investment Objectives and Strategies	15
Fund Investments	15
Additional Risks of Investing in the Fund	19
Fund Organization	25
Management of the Fund	25
How to Buy and Sell Shares	29
Dividends, Distributions and Taxes	31
Federal Tax Matters	31
Distribution Plan	33
Net Asset Value	33
Fund Service Providers	35
Premium/Discount Information	35
Total Return Information	35
Financial Highlights	37
Other Information	38

Investment Objectives

The First Trust Strategic Income ETF's (the " Fund ") primary investment objective is to seek risk-adjusted income. The Fund’s secondary investment objective is capital appreciation.

Fees and Expenses of the Fund

The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund. Investors purchasing and selling shares may be subject to costs (including customary brokerage commissions) charged by their broker, which are not reflected in the table below.

Shareholder Fees
(fees paid directly from your investment)

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

None

    

3