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Summary of the Fund

Columbia Overseas Core Fund

Summary of the Fund (continued)

■	the Fund’s total annual operating expenses remain the same as shown in the Annual Fund Operating Expenses table above.

Since the waivers and/or reimbursements shown in the Annual Fund Operating Expenses table above expire as indicated in the preceding table, they are only reflected in the 1 year example and the first year of the 3 year example. Although your actual costs may be higher or lower, based on the assumptions listed above, your costs (based on estimated Fund expenses) would be:

    

Portfolio Turnover

The Fund may pay 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. Because the Fund is newly organized, portfolio turnover information is not available as of the date of this prospectus.

Principal Investment Strategies

Under normal circumstances, the Fund invests at least 80% of its net assets (including the amount of any borrowings for investment purposes) in equity securities of foreign companies. The Fund may invest up to 20% of its net assets in emerging market countries. The Fund may invest directly in foreign equity securities, such as common and preferred stock, or indirectly through mutual funds and closed-end funds, as well as depositary receipts. The Fund may invest in securities of or relating to issuers believed to be undervalued (i.e., “value” stocks), represent growth opportunities (i.e., “growth” stocks), or both. The Fund may invest in the securities of issuers of any size, including small-, mid- and large-capitalization companies.

The Fund may invest in companies involved in initial public offerings, tender offers, mergers, other corporate restructurings and other special situations. From time to time, the Fund may focus its investments in certain countries or geographic areas, including the Asia/Pacific region and Europe. The Fund may from time to time emphasize one or more sectors in selecting its investments, including the financial services sector.

The Fund may invest in derivatives, such as forward contracts (including forward foreign currency contracts), futures (including equity futures and index futures) and options (including options on stocks and indices), for both hedging and non-hedging purposes including, for example, for investment purposes to seek to enhance returns or, in certain circumstances, when holding a derivative is deemed preferable to holding the underlying asset. In particular, the Fund may invest in forward currency contracts to hedge the currency exposure associated with some or all of the Fund’s securities, to shift investment exposure from one currency to another, to shift U.S. dollar exposure to achieve a representative weighted mix of major currencies in its benchmark, or to adjust an underweight country exposure in its portfolio. The Fund may also invest in equity index futures to manage exposure to the securities market and to maintain equity market exposure while managing cash flows.

The Fund’s investment strategy may involve the frequent trading of portfolio securities.

4	Prospectus 2018

Columbia Overseas Core Fund

Summary of the Fund (continued)

Columbia Overseas Core Fund

Summary of the Fund (continued)

illiquidity, unusually high trading volume and other negative impacts, such as political intervention, which may result in volatility or disruptions in such markets. A relatively small price movement in a forward contract may result in substantial losses to the Fund, exceeding the amount of the margin paid. Forward contracts can increase the Fund’s risk exposure to underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while also exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

Derivatives Risk – Futures Contracts Risk. A futures contract is an exchange-traded derivative transaction between two parties in which a buyer (holding the “long” position) agrees to pay a fixed price (or rate) at a specified future date for delivery of an underlying reference from a seller (holding the “short” position). The seller hopes that the market price on the delivery date is less than the agreed upon price, while the buyer hopes for the contrary. Certain futures contract markets are highly volatile, and futures contracts may be illiquid. Futures exchanges may limit fluctuations in futures contract prices by imposing a maximum permissible daily price movement. The Fund may be disadvantaged if it is prohibited from executing a trade outside the daily permissible price movement. At or prior to maturity of a futures contract, the Fund may enter into an offsetting contract and may incur a loss to the extent there has been adverse movement in futures contract prices. The liquidity of the futures markets depends on participants entering into offsetting transactions rather than making or taking delivery. To the extent participants make or take delivery, liquidity in the futures market could be reduced. Because of the low margin deposits normally required in futures trading, it is possible that the Fund may employ a high degree of leverage in the portfolio. As a result, a relatively small price movement in a futures contract may result in substantial losses to the Fund, exceeding the amount of the margin paid. For certain types of futures contracts, losses are potentially unlimited. Futures markets are highly volatile and the use of futures may increase the volatility of the Fund’s NAV. Futures contracts executed (if any) on foreign exchanges may not provide the same protection as U.S. exchanges. Futures contracts can increase the Fund’s risk exposure to underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while also exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

Derivatives Risk – Options Risk. Options are derivatives that give the purchaser the option to buy (call) or sell (put) an underlying reference from or to a counterparty at a specified price (the strike price) on or before an expiration date. By investing in options, the Fund is exposed to the risk that it may be required to buy or sell the underlying reference at a disadvantageous price on or before the expiration date. Options may involve economic leverage, which could result in greater volatility in price movement. The Fund's losses could be significant, and are potentially unlimited for certain types of options. Options may be traded on a securities exchange or in the over-the-counter market. At or prior to maturity of an options contract, the Fund may enter into an offsetting contract and may incur a loss to the extent there has been adverse movement in options prices. Options can increase the Fund’s risk exposure to underlying references and their attendant risks such as credit risk, market risk, foreign currency risk and interest rate risk, while also exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

Emerging Market Securities Risk. Securities issued by foreign governments or companies in emerging market countries, such as China, Russia and certain countries in Eastern Europe, the Middle East, Asia, Latin America or Africa, are more likely to have greater exposure to the risks of investing in foreign securities that are described in Foreign Securities Risk. In addition, emerging market countries are more likely to experience instability resulting, for example, from rapid changes or developments in social, political, economic or other conditions. Their economies are usually less mature and their securities markets are typically less developed with more limited trading activity (i.e., lower trading volumes and less liquidity) than more developed countries. Emerging market securities tend to be more volatile than securities in more developed markets. Many emerging market countries are heavily dependent on international trade and have fewer trading partners, which makes them more sensitive to world commodity prices and economic downturns in other countries, and some have a higher risk of currency devaluations.

Foreign Securities Risk. Investments in or exposure to foreign securities involve certain risks not associated with investments in or exposure to securities of U.S. companies. Foreign securities subject the Fund to the risks associated with investing in the particular country of an issuer, including political, regulatory, economic, social, diplomatic and other conditions or events (including, for example, military confrontations, war and terrorism),

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Summary of the Fund (continued)

occurring in the country or region, as well as risks associated with less developed custody and settlement practices. Foreign securities may be more volatile and less liquid than securities of U.S. companies, and are subject to the risks associated with potential imposition of economic and other sanctions against a particular foreign country, its nationals or industries or businesses within the country. In addition, foreign governments may impose withholding or other taxes on the Fund’s income, capital gains or proceeds from the disposition of foreign securities, which could reduce the Fund’s return on such securities. The performance of the Fund may also be negatively affected by fluctuations in a foreign currency's strength or weakness relative to the U.S. dollar, particularly to the extent the Fund invests a significant percentage of its assets in foreign securities or other assets denominated in currencies other than the U.S. dollar.

Frequent Trading Risk.  The portfolio managers may actively and frequently trade investments in the Fund's portfolio to carry out its investment strategies. Frequent trading of investments increases the possibility that the Fund, as relevant, will realize taxable capital gains (including short-term capital gains, which are generally taxable to shareholders at higher rates than long-term capital gains for U.S. federal income tax purposes), which could reduce the Fund's after-tax return. Frequent trading can also mean higher brokerage and other transaction costs, which could reduce the Fund's return. The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund’s performance.

Geographic Focus Risk. The Fund may be particularly susceptible to economic, political, regulatory or other events or conditions affecting issuers and countries within the specific geographic regions in which the Fund invests. The Fund’s NAV may be more volatile than the NAV of a more geographically diversified fund.

Asia Pacific Region. Many of the countries in the Asia Pacific region are considered underdeveloped or developing, including from a political, economic and/or social perspective, and may have relatively unstable governments and economies based on limited business, industries and/or natural resources or commodities. Events in any one country within the region may impact other countries in the region or the region as a whole. As a result, events in the region will generally have a greater effect on the Fund than if the Fund were more geographically diversified. This could result in increased volatility in the value of the Fund’s investments and losses for the Fund. Also, securities of some companies in the region can be less liquid than U.S. or other foreign securities, potentially making it difficult for the Fund to sell such securities at a desirable time and price.

Europe. The Fund is particularly susceptible to economic, political, regulatory or other events or conditions affecting issuers and countries in Europe. In addition, the private and public sectors’ debt problems of a single European Union (EU) country can pose significant economic risks to the EU as a whole. As a result, the Fund’s NAV may be more volatile than the NAV of a more geographically diversified fund. If securities of issuers in Europe fall out of favor, it may cause the Fund to underperform other funds that do not focus their investments in this region of the world. The impact of any partial or complete dissolution of the EU on European economies could be significant, resulting in negative impacts on currency and financial markets generally, such as increased volatility and illiquidity, and potentially lower economic growth in markets in Europe, which may adversely affect the value of your investment in the Fund.

Growth Securities Risk. Growth securities typically trade at a higher multiple of earnings than other types of equity securities. Accordingly, the market values of growth securities may never reach their expected market value and may decline in price. In addition, growth securities, at times, may not perform as well as value securities or the stock market in general, and may be out of favor with investors for varying periods of time.

Investing in Other Funds Risk. The Fund’s investment in other funds (affiliated and/or unaffiliated funds, including exchange-traded funds (ETFs)) subjects the Fund to the investment performance (positive or negative) and risks of the underlying funds in direct proportion to the Fund’s investment therein. In addition, investments in ETFs have unique characteristics, including, but not limited to, the expense structure and additional expenses associated with investing in ETFs. The performance of the underlying funds could be adversely affected if other investors in the same underlying funds make relatively large investments or redemptions in such underlying funds. The Fund, and its shareholders, indirectly bear a portion of the expenses of any funds in which the Fund invests. Because the expenses and costs of an underlying fund are shared by its investors, redemptions by other investors in the underlying funds could result in decreased economies of scale and increased operating expenses for such underlying

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Summary of the Fund (continued)

funds. The Investment Manager may have potential conflicts of interest in selecting affiliated underlying funds for investment by the Fund because the fees paid to it by some underlying funds are higher than the fees paid by other underlying funds, as well as a potential conflict in selecting affiliated funds over unaffiliated funds. Also, to the extent that the Fund is constrained/restricted from investing (or investing further) in a particular underlying fund for one or more reasons (e.g., underlying fund capacity constraints or regulatory restrictions) or if the Fund chooses to sell its investment in an underlying fund because of poor investment performance or for other reasons, the Fund may have to invest in other underlying funds, including less desirable funds – from a strategy or investment performance standpoint – which could have a negative impact on Fund performance. In addition, Fund performance could be negatively impacted if an appropriate alternate underlying fund does not present itself in a timely manner or at all. The underlying funds may not achieve their investment objective. The Fund, through its investment in underlying funds, may not achieve its investment objective.

Issuer Risk. An issuer in which the Fund invests or to which it has exposure may perform poorly, and the value of its securities may therefore decline, which would negatively affect the Fund’s performance. Poor performance may be caused by poor management decisions, competitive pressures, breakthroughs in technology, reliance on suppliers, labor problems or shortages, corporate restructurings, fraudulent disclosures, natural disasters or other events, conditions or factors. The market capitalization of an issuer may also impact its risk profile. Investments in larger, more established companies may involve certain risks associated with their larger size. For instance, larger, more established companies may be less able to respond quickly to new competitive challenges, such as changes in consumer tastes or innovation from smaller competitors. Also, larger companies are sometimes less able to attain the high growth rates of successful smaller companies, especially during extended periods of economic expansion.

Liquidity Risk. Liquidity risk is the risk associated with any event, circumstance, or characteristic of an investment or market that negatively impacts the Fund’s ability to sell, or realize the proceeds from the sale of, an investment at a desirable time or price. Liquidity risk may arise because of, for example, a lack of marketability of the investment, which means that when seeking to sell its portfolio investments, the Fund could find that selling is more difficult than anticipated, especially during times of high market volatility. Market participants attempting to sell the same or a similar instrument at the same time as the Fund could exacerbate the Fund’s exposure to liquidity risk. The Fund may have to accept a lower selling price for the holding, sell other liquid or more liquid investments that it might otherwise prefer to hold (thereby increasing the proportion of the Fund’s investments in less liquid or illiquid securities), or forego another more appealing investment opportunity. Certain investments that were liquid when purchased by the Fund may later become illiquid, particularly in times of overall economic distress. Changing regulatory, market or other conditions or environments (for example, the interest rate or credit environments) may also adversely affect the liquidity and the price of the Fund's investments. Judgment plays a larger role in valuing illiquid or less liquid investments as compared to valuing liquid or more liquid investments. Price volatility may be higher for illiquid or less liquid investments as a result of, for example, the relatively less frequent pricing of such securities (as compared to liquid or more liquid investments). Generally, the less liquid the market at the time the Fund sells a portfolio investment, the greater the risk of loss or decline of value to the Fund. Overall market liquidity and other factors can lead to an increase in redemptions, which may negatively impact Fund performance and NAV, including, for example, if the Fund is forced to sell investments in a down market. Foreign securities can present enhanced liquidity risks, including as a result of less developed custody, settlement or other practices of foreign markets.

Market Risk. Market risk refers to the possibility that the market values of securities or other investments that the Fund holds will fall, sometimes rapidly or unpredictably, or fail to rise. An investment in the Fund could lose money over short or long periods.

New Fund Risk. Investors in newly formed funds bear the risk that the fund may not be successful in implementing its investment strategy, and may not employ a successful investment strategy, either of which could result in the fund being liquidated at any time without shareholder approval and/or at a time that may not be favorable for certain shareholders. Such a liquidation could have negative tax consequences for shareholders.

Preferred Stock Risk. Preferred stock is a type of stock that generally pays dividends at a specified rate and that has preference over common stock in the payment of dividends and the liquidation of assets. Preferred stock does not ordinarily carry voting rights. The price of a preferred stock is generally determined by earnings, type of products or

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Summary of the Fund (continued)

services, projected growth rates, experience of management, liquidity, and general market conditions of the markets on which the stock trades. The most significant risks associated with investments in preferred stock include issuer risk, market risk and interest rate risk ( i.e. , the risk of losses attributable to changes in interest rates).

Sector Risk. At times, the Fund may have a significant portion of its assets invested in securities of companies conducting business in a related group of industries within a sector, including the financial services sector. Companies in the same sector may be similarly affected by economic, regulatory, political or market events or conditions, which may make the Fund more vulnerable to unfavorable developments in that sector than funds that invest more broadly. Generally, the more broadly the Fund invests, the more it spreads risk and potentially reduces the risks of loss and volatility.

Financial Services Sector. The Fund may be more susceptible to the particular risks that may affect companies in the financial services sector than if it were invested in a wider variety of companies in unrelated sectors. Companies in the financial services sector are subject to certain risks, including the risk of regulatory change, decreased liquidity in credit markets and unstable interest rates. Such companies may have concentrated portfolios, such as a high level of loans to real estate developers, which makes them vulnerable to economic conditions that affect that industry. Performance of such companies may be affected by competitive pressures and exposure to investments or agreements that, under certain circumstances, may lead to losses (e.g., subprime loans). Companies in the financial services sector are subject to extensive governmental regulation that may limit the amount and types of loans and other financial commitments they can make, and interest rates and fees that they may charge. In addition, profitability of such companies is largely dependent upon the availability and the cost of capital.

Small- and Mid-Cap Company Securities Risk. Investments in small- and mid-capitalization companies (small- and mid-cap companies) often involve greater risks than investments in larger, more established companies (larger companies) because small- and mid-cap companies tend to have less predictable earnings and may lack the management experience, financial resources, product diversification and competitive strengths of larger companies. Securities of small- and mid-cap companies may be less liquid and more volatile than the securities of larger companies.

Special Situations Risk. Securities of companies that are involved in an initial public offering or a major corporate event, such as a business consolidation or restructuring, may be exposed to heightened risk because of the high degree of uncertainty that can be associated with such events. Securities issued in initial public offerings often are issued by companies that are in the early stages of development, have a history of little or no revenues and may operate at a loss following the offering. It is possible that there will be no active trading market for the securities after the offering, and that the market price of the securities may be subject to significant and unpredictable fluctuations. Certain “special situation” investments are investments in securities or other instruments that are determined to be illiquid or lacking a readily ascertainable fair value. Certain special situation investments prevent ownership interests therein from being withdrawn until the special situation investment, or a portion thereof, is realized or deemed realized, which may negatively impact Fund performance. Investing in special situations may have a magnified effect on the performance of funds with small amounts of assets.

Value Securities Risk. Value securities are securities of companies that may have experienced, for example, adverse business, industry or other developments or may be subject to special risks that have caused the securities to be out of favor and, in turn, potentially undervalued. The market value of a portfolio security may not meet portfolio management’s perceived value assessment of that security, or may decline in price, even though portfolio management believes the securities are already undervalued. There is also a risk that it may take longer than expected for the value of these investments to rise to portfolio management’s perceived value. In addition, value securities, at times, may not perform as well as growth securities or the stock market in general, and may be out of favor with investors for varying periods of time.

Performance Information

The Fund is new as of the date of this prospectus and therefore performance information is not available.

When available, the Fund intends to compare its performance to the performance of the MSCI EAFE Index (Net).

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Summary of the Fund (continued)

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), the Fund and its related companies — including Columbia Management Investment Advisers, LLC (the Investment Manager), Columbia Management Investment Distributors, Inc. (the Distributor) and Columbia Management Investment Services Corp. (the Transfer Agent) — 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 financial advisor to recommend the Fund over another investment. Ask your financial advisor or visit your financial intermediary’s website for more information.

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Columbia Overseas Core Fund

More Information About the Fund

Columbia Overseas Core Fund

More Information About the Fund (continued)

Columbia Overseas Core Fund

More Information About the Fund (continued)

loss due to a derivative position that is imperfectly correlated with the underlying reference it is intended to hedge or replicate (correlation risk), the risk that a counterparty will fail to perform as agreed (counterparty risk), the risk that a hedging strategy may fail to mitigate losses, and may offset gains (hedging risk), the risk that losses may be greater than the amount invested (leverage risk), the risk that the Fund may be unable to sell an investment at an advantageous time or price (liquidity risk), the risk that the investment may be difficult to value (pricing risk), and the risk that the price or value of the investment fluctuates significantly over short periods of time (volatility risk). The value of derivatives may be influenced by a variety of factors, including national and international political and economic developments. Potential changes to the regulation of the derivatives markets may make derivatives more costly, may limit the market for derivatives, or may otherwise adversely affect the value or performance of derivatives.

Derivatives Risk – Forward Contracts Risk. A forward contract is an over-the-counter derivative transaction between two parties to buy or sell a specified amount of an underlying reference at a specified price (or rate) on a specified date in the future. Forward contracts are negotiated on an individual basis and are not standardized or traded on exchanges. The market for forward contracts is substantially unregulated (there is no limit on daily price movements and speculative position limits are not applicable). The principals who deal in certain forward contract markets are not required to continue to make markets in the underlying references in which they trade and these markets can experience periods of illiquidity, sometimes of significant duration. There have been periods during which certain participants in forward contract markets have refused to quote prices for certain underlying references or have quoted prices with an unusually wide spread between the price at which they were prepared to buy and that at which they were prepared to sell. At or prior to maturity of a forward contract, the Fund may enter into an offsetting contract and may incur a loss to the extent there has been adverse movement in forward contract prices. The liquidity of the markets for forward contracts depends on participants entering into offsetting transactions rather than making or taking delivery. To the extent participants make or take delivery, liquidity in the market for forwards could be reduced. A relatively small price movement in a forward contract may result in substantial losses to the Fund, exceeding the amount of the margin paid. Forward contracts can increase the Fund’s risk exposure to underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while also exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

■

A forward foreign currency contract is a derivative (forward contract) in which the underlying reference is a country's or region’s currency. The Fund may agree to buy or sell a country's or region’s currency at a specific price on a specific date in the future. These instruments may fall in value (sometimes dramatically) due to foreign market downswings or foreign currency value fluctuations, subjecting the Fund to foreign currency risk (the risk that Fund performance may be negatively impacted by foreign currency strength or weakness relative to the U.S. dollar, particularly if the Fund exposes a significant percentage of its assets to currencies other than the U.S. dollar). Unanticipated changes in the currency markets could result in reduced performance for the Fund. When the Fund converts its foreign currencies into U.S. dollars, it may incur currency conversion costs due to the spread between the prices at which it may buy and sell various currencies in the market.

Derivatives Risk – Futures Contracts Risk. A futures contract is an exchange-traded derivative transaction between two parties in which a buyer (holding the “long” position) agrees to pay a fixed price (or rate) at a specified future date for delivery of an underlying reference from a seller (holding the “short” position). The seller hopes that the market price on the delivery date is less than the agreed upon price, while the buyer hopes for the contrary. Certain futures contract markets are highly volatile, and futures contracts may be illiquid. Futures exchanges may limit fluctuations in futures contract prices by imposing a maximum permissible daily price movement. The Fund may be disadvantaged if it is prohibited from executing a trade outside the daily permissible price movement. At or prior to maturity of a futures contract, the Fund may enter into an offsetting contract and may incur a loss to the extent there has been adverse movement in futures contract prices. The liquidity of the futures markets depends on participants entering into offsetting transactions rather than making or taking delivery. To the extent participants make or take delivery, liquidity in the futures market could be reduced. Positions in futures contracts may be closed out only on the exchange on which they were entered into or through a linked exchange, and no secondary market exists for such contracts. Futures positions are marked to market each day and variation margin payment must be paid to or by the Fund. Because of the low margin deposits normally required in futures trading, it is possible that the Fund may

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More Information About the Fund (continued)

employ a high degree of leverage in the portfolio. As a result, a relatively small price movement in a futures contract may result in substantial losses to the Fund, exceeding the amount of the margin paid. For certain types of futures contracts, losses are potentially unlimited. Futures markets are highly volatile and the use of futures may increase the volatility of the Fund’s NAV. Futures contracts executed (if any) on foreign exchanges may not provide the same protection as U.S. exchanges. Futures contracts can increase the Fund’s risk exposure to underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while also exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

■	An equity future is a derivative that is an agreement for the contract holder to buy or sell a specified amount of an individual equity, a basket of equities or the securities in an equity index on a specified date at a predetermined price.

Derivatives Risk – Options Risk. Options are derivatives that give the purchaser the option to buy (call) or sell (put) an underlying reference from or to a counterparty at a specified price (the strike price) on or before an expiration date. The Fund may purchase or write (i.e., sell) put and call options on an underlying reference it is otherwise permitted to invest in. By investing in options, the Fund is exposed to the risk that it may be required to buy or sell the underlying reference at a disadvantageous price on or before the expiration date. If the Fund sells a put option, the Fund may be required to buy the underlying reference at a strike price that is above market price, resulting in a loss. If the Fund sells a call option, the Fund may be required to sell the underlying reference at a strike price that is below market price, resulting in a loss. If the Fund sells a call option that is not covered (it does not own the underlying reference), the Fund's losses are potentially unlimited. Options may involve economic leverage, which could result in greater volatility in price movement. Options may be traded on a securities exchange or in the over-the-counter market. At or prior to maturity of an options contract, the Fund may enter into an offsetting contract and may incur a loss to the extent there has been adverse movement in options prices. Options can increase the Fund’s risk exposure to underlying references and their attendant risks such as credit risk, market risk, foreign currency risk and interest rate risk, while also exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

Emerging Market Securities Risk. Securities issued by foreign governments or companies in emerging market countries, such as China, Russia and certain countries in Eastern Europe, the Middle East, Asia, Latin America or Africa, are more likely to have greater exposure to the risks of investing in foreign securities that are described in Foreign Securities Risk. In addition, emerging market countries are more likely to experience instability resulting, for example, from rapid changes or developments in social, political, economic or other conditions. Their economies are usually less mature and their securities markets are typically less developed with more limited trading activity ( i.e. , lower trading volumes and less liquidity) than more developed countries. Emerging market securities tend to be more volatile than securities in more developed markets. Many emerging market countries are heavily dependent on international trade and have fewer trading partners, which makes them more sensitive to world commodity prices and economic downturns in other countries. Some emerging market countries have a higher risk of currency devaluations, and some of these countries may experience periods of high inflation or rapid changes in inflation rates and may have hostile relations with other countries.

Foreign Securities Risk. Investments in or exposure to foreign securities involve certain risks not associated with investments in or exposure to securities of U.S. companies. For example, foreign markets can be extremely volatile. Foreign securities may also be less liquid than securities of U.S. companies so that the Fund may, at times, be unable to sell foreign securities at desirable times or prices. Brokerage commissions, custodial costs and other fees are also generally higher for foreign securities. The Fund may have limited or no legal recourse in the event of default with respect to certain foreign securities, including those issued by foreign governments. In addition, foreign governments may impose withholding or other taxes on the Fund’s income, capital gains or proceeds from the disposition of foreign securities, which could reduce the Fund’s return on such securities. In some cases, such withholding or other taxes could potentially be confiscatory. Other risks include: possible delays in the settlement of transactions or in the payment of income; generally less publicly available information about foreign companies; the impact of economic, political, social, diplomatic or other conditions or events (including, for example, military confrontations, war and terrorism), possible seizure, expropriation or nationalization of a company or its assets or the assets of a particular investor or category of investors; accounting, auditing and financial reporting standards that

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More Information About the Fund (continued)

may be less comprehensive and stringent than those applicable to domestic companies; the imposition of economic and other sanctions against a particular foreign country, its nationals or industries or businesses within the country; and the generally less stringent standard of care to which local agents may be held in the local markets. In addition, it may be difficult to obtain reliable information about the securities and business operations of certain foreign issuers. Governments or trade groups may compel local agents to hold securities in designated depositories that are not subject to independent evaluation. The less developed a country’s securities market is, the greater the level of risks. The risks posed by sanctions against a particular foreign country, its nationals or industries or businesses within the country may be heightened to the extent the Fund invests significantly in the affected country or region or in issuers from the affected country that depend on global markets. Additionally, investments in certain countries may subject the Fund to a number of tax rules, the application of which may be uncertain. Countries may amend or revise their existing tax laws, regulations and/or procedures in the future, possibly with retroactive effect. Changes in or uncertainties regarding the laws, regulations or procedures of a country could reduce the after-tax profits of the Fund, directly or indirectly, including by reducing the after-tax profits of companies located in such countries in which the Fund invests, or result in unexpected tax liabilities for the Fund. The performance of the Fund may also be negatively affected by fluctuations in a foreign currency's strength or weakness relative to the U.S. dollar, particularly to the extent the Fund invests a significant percentage of its assets in foreign securities or other assets denominated in currencies other than the U.S. dollar. Currency rates in foreign countries may fluctuate significantly over short or long periods of time for a number of reasons, including changes in interest rates, imposition of currency exchange controls and economic or political developments in the U.S. or abroad. The Fund may also incur currency conversion costs when converting foreign currencies into U.S. dollars and vice versa.

Frequent Trading Risk.  The portfolio managers may actively and frequently trade investments in the Fund's portfolio to carry out its investment strategies. Frequent trading of investments increases the possibility that the Fund, as relevant, will realize taxable capital gains (including short-term capital gains, which are generally taxable to shareholders at higher rates than long-term capital gains for U.S. federal income tax purposes), which could reduce the Fund's after-tax return. Frequent trading can also mean higher brokerage and other transaction costs, which could reduce the Fund's return. The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund’s performance.

Geographic Focus Risk. The Fund may be particularly susceptible to economic, political, regulatory or other events or conditions affecting issuers and countries within the specific geographic regions in which the Fund invests. Currency devaluations could occur in countries that have not yet experienced currency devaluation to date, or could continue to occur in countries that have already experienced such devaluations. As a result, the Fund’s NAV may be more volatile than the NAV of a more geographically diversified fund.

Asia Pacific Region. A number of countries in the Asia Pacific region are considered underdeveloped or developing, including from a political, economic and/or social perspective, and may have relatively unstable governments and economies based on limited business, industries and/or natural resources or commodities. Events in any one country within the region may impact that country, other countries in the region or the region as a whole. As a result, events in the region will generally have a greater effect on the Fund than if the Fund were more geographically diversified in areas with more developed countries and economies. This could result in increased volatility in the value of the Fund’s investments and losses for the Fund. Continued growth of economies and securities markets in the region will require sustained economic and fiscal discipline, as well as continued commitment to governmental and regulatory reforms. Development also may be influenced by international economic conditions, including those in the United States and Japan, and by world demand for goods or natural resources produced in countries in the Asia Pacific region. Securities markets in the region are generally smaller and have a lower trading volume than those in the United States, which may result in the securities of some companies in the region being less liquid than U.S. or other foreign securities. Some currencies, inflation rates or interest rates in the Asia Pacific region are or can be volatile, and some countries in the region may restrict the flow of money in and out of the country. The risks described under “Emerging Market Securities Risk” and  “Foreign Securities Risk” may be more pronounced due to the Fund’s focus on investments in the region.

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Europe. The Fund is particularly susceptible to economic, political, regulatory or other events or conditions affecting issuers and countries in Europe. Most developed countries in Western Europe are members of the European Union (EU), and many are also members of the European Economic and Monetary Union (EMU). European countries can be significantly affected by the tight fiscal and monetary controls that the EMU imposes on its members and with which candidates for EMU membership are required to comply. In addition, the private and public sectors’ debt problems of a single EU country can pose significant economic risks to the EU as a whole. Unemployment in Europe has historically been higher than in the United States and public deficits are an ongoing concern in many European countries. As a result, the Fund’s NAV may be more volatile than the NAV of a more geographically diversified fund. If securities of issuers in Europe fall out of favor, it may cause the Fund to underperform other funds that do not focus their investments in this region of the world. At a referendum in June 2016, the United Kingdom (the UK) voted to leave the EU (commonly known as “Brexit”).  However, there is a significant degree of uncertainty about how negotiations relating to the UK’s withdrawal and new trade agreements will be conducted, as well as the potential consequences and precise timeframe for Brexit.  The impact of any partial or complete dissolution of the EU on the UK and European economies and the broader global economy could be significant, resulting in negative impacts on currency and financial markets generally, such as increased volatility and illiquidity, and potentially lower economic growth in markets in the UK, Europe and globally, which may adversely affect the value of your investment in the Fund.  The impact of Brexit in the near- and long-term is still unknown and could have additional adverse effects on economies, financial markets, currencies and asset valuations around the world. Any attempt by the Fund to hedge against or otherwise protect its portfolio or to profit from such circumstances may fail and, accordingly, an investment in the Fund could lose money over short or long periods.  For more information on the risks associated with Brexit, see the SAI. 

Growth Securities Risk. Growth securities typically trade at a higher multiple of earnings than other types of equity securities. Accordingly, the market values of growth securities may never reach their expected market value and may decline in price. In addition, growth securities, at times, may not perform as well as value securities or the stock market in general, and may be out of favor with investors for varying periods of time.

Investing in Other Funds Risk. The Fund’s investment in other funds (affiliated and/or unaffiliated funds, including exchange-traded funds (ETFs)) subjects the Fund to the investment performance (positive or negative) and risks of the underlying funds in direct proportion to the Fund’s investment therein. In addition, investments in ETFs have unique characteristics, including, but not limited to, the expense structure and additional expenses associated with investing in ETFs. The performance of the underlying funds could be adversely affected if other investors in the same underlying funds make relatively large investments or redemptions in such underlying funds. The Fund, and its shareholders, indirectly bear a portion of the expenses of any funds in which the Fund invests. Because the expenses and costs of an underlying fund are shared by its investors, redemptions by other investors in the underlying funds could result in decreased economies of scale and increased operating expenses for such underlying fund. These transactions might also result in higher brokerage, tax or other costs for the underlying funds. This risk may be particularly important when one investor owns a substantial portion of the underlying funds. The Investment Manager may have potential conflicts of interest in selecting affiliated underlying funds for investment by the Fund because the fees paid to it by some underlying funds are higher than the fees paid by other underlying funds, as well as a potential conflict in selecting affiliated funds over unaffiliated funds. Also, to the extent that the Fund is constrained/restricted from investing (or investing further) in a particular underlying fund for one or more reasons (e.g., underlying fund capacity constraints or regulatory restrictions) or if the Fund chooses to sell its investment in an underlying fund because of poor investment performance or for other reasons, the Fund may have to invest in other underlying funds, including less desirable funds – from a strategy or investment performance standpoint – which could have a negative impact on Fund performance. In addition, Fund performance could be negatively impacted if an appropriate alternate underlying fund does not present itself in a timely manner or at all.

Issuer Risk. An issuer in which the Fund invests or to which it has exposure may perform poorly, and the value of its securities may therefore decline, which would negatively affect the Fund’s performance. Poor performance may be caused by poor management decisions, competitive pressures, breakthroughs in technology, reliance on suppliers, labor problems or shortages, corporate restructurings, fraudulent disclosures, natural disasters or other events, conditions or factors. The market capitalization of an issuer may also impact its risk profile. Investments in larger,

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more established companies may involve certain risks associated with their larger size. For instance, larger, more established companies may be less able to respond quickly to new competitive challenges, such as changes in consumer tastes or innovation from smaller competitors. Also, larger companies are sometimes less able to attain the high growth rates of successful smaller companies, especially during extended periods of economic expansion.

Liquidity Risk. Liquidity risk is the risk associated with any event, circumstance, or characteristic of an investment or market that negatively impacts the Fund’s ability to sell, or realize the proceeds from the sale of, an investment at a desirable time or price. Liquidity risk may arise because of, for example, a lack of marketability of the investment, which means that when seeking to sell its portfolio investments, the Fund could find that selling is more difficult than anticipated, especially during times of high market volatility. Market participants attempting to sell the same or a similar instrument at the same time as the Fund could exacerbate the Fund’s exposure to liquidity risk. The Fund may have to accept a lower selling price for the holding, sell other liquid or more liquid investments that it might otherwise prefer to hold (thereby increasing the proportion of the Fund’s investments in less liquid or illiquid securities), or forego another more appealing investment opportunity. Certain investments that were liquid when purchased by the Fund may later become illiquid, particularly in times of overall economic distress. Changing regulatory, market or other conditions or environments (for example, the interest rate or credit environments) may also adversely affect the liquidity and the price of the Fund's investments. Judgment plays a larger role in valuing illiquid or less liquid investments as compared to valuing liquid or more liquid investments. Price volatility may be higher for illiquid or less liquid investments as a result of, for example, the relatively less frequent pricing of such securities (as compared to liquid or more liquid investments). Generally, the less liquid the market at the time the Fund sells a portfolio investment, the greater the risk of loss or decline of value to the Fund. Overall market liquidity and other factors can lead to an increase in redemptions, which may negatively impact Fund performance and NAV, including, for example, if the Fund is forced to sell investments in a down market. Foreign securities can present enhanced liquidity risks, including as a result of less developed custody, settlement or other practices of foreign markets.

Market Risk. Market risk refers to the possibility that the market values of securities or other investments that the Fund holds will fall, sometimes rapidly or unpredictably, or fail to rise. The value of Fund investments may fall or fail to rise because of a variety of actual or perceived factors affecting an issuer (e.g., an unfavorable earnings report), the industry or sector in which it operates, or the market as a whole, which may reduce the value of an investment in the Fund. Accordingly, an investment in the Fund could lose money over short or long periods. The market values of the investments the Fund holds can be affected by changes or potential or perceived changes in U.S. or foreign economies, financial markets, interest rates and the liquidity of these investments, among other factors.

New Fund Risk. Investors in newly formed funds bear the risk that the fund may not be successful in implementing its investment strategy, and may not employ a successful investment strategy, either of which could result in the fund being liquidated at any time without shareholder approval and/or at a time that may not be favorable for certain shareholders. Such a liquidation could have negative tax consequences for shareholders.

Preferred Stock Risk. Preferred stock is a type of stock that generally pays dividends at a specified rate and that has preference over common stock in the payment of dividends and the liquidation of assets. Preferred stock does not ordinarily carry voting rights. The price of a preferred stock is generally determined by earnings, type of products or services, projected growth rates, experience of management, liquidity, and general market conditions of the markets on which the stock trades. The most significant risks associated with investments in preferred stock include issuer risk, market risk and interest rate risk ( i.e. , the risk of losses attributable to changes in interest rates).

Sector Risk. At times, the Fund may have a significant portion of its assets invested in securities of companies conducting business in a related group of industries within a sector, including the financial services sector. Companies in the same sector may be similarly affected by economic, regulatory, political or market events or conditions, which may make the Fund more vulnerable to unfavorable developments in that sector than funds that invest more broadly. Generally, the more broadly the Fund invests, the more it spreads risk and potentially reduces the risks of loss and volatility.

Financial Services Sector. The Fund may be more susceptible to the particular risks that may affect companies in the financial services sector than if it were invested in a wider variety of companies in unrelated sectors. Companies in the financial services sector are subject to certain risks, including the risk of regulatory change, decreased liquidity

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in credit markets and unstable interest rates. Such companies may have concentrated portfolios, such as a high level of loans to real estate developers, which makes them vulnerable to economic conditions that affect that industry. Performance of such companies may be affected by competitive pressures and exposure to investments or agreements that, under certain circumstances, may lead to losses (e.g., subprime loans). Companies in the financial services sector are subject to extensive governmental regulation that may limit the amount and types of loans and other financial commitments they can make, and interest rates and fees that they may charge. In addition, profitability of such companies is largely dependent upon the availability and the cost of capital.

Small- and Mid-Cap Company Securities Risk. Securities of small- and mid-capitalization companies (small- and mid-cap companies) can, in certain circumstances, have a higher potential for gains than securities of larger, more established companies (larger companies) but may also have more risk. For example, small- and mid-cap companies may be more vulnerable to market downturns and adverse business or economic events than larger companies because they may have more limited financial resources and business operations. Small- and mid-cap companies are also more likely than larger companies to have more limited product lines and operating histories and to depend on smaller and generally less experienced management teams. Securities of small- and mid-cap companies may trade less frequently and in smaller volumes and may be less liquid and fluctuate more sharply in value than securities of larger companies. When the Fund takes significant positions in small- and mid-cap companies with limited trading volumes, the liquidation of those positions, particularly in a distressed market, could be prolonged and result in Fund investment losses that would affect the value of your investment in the Fund. In addition, some small- and mid-cap companies may not be widely followed by the investment community, which can lower the demand for their stocks.

Special Situations Risk. Securities of companies that are involved in an initial public offering or a major corporate event, such as a business consolidation or restructuring, may be exposed to heightened risk because of the high degree of uncertainty that can be associated with such events. Securities issued in initial public offerings often are issued by companies that are in the early stages of development, have a history of little or no revenues and may operate at a loss following the offering. It is possible that there will be no active trading market for the securities after the offering, and that the market price of the securities may be subject to significant and unpredictable fluctuations. Initial public offerings are subject to many of the same risks as investing in companies with smaller market capitalizations. To the extent the Fund determines to invest in initial public offerings, it may not be able to invest to the extent desired, because, for example, only a small portion (if any) of the securities being offered in an initial public offering are available to the Fund. The investment performance of the Fund during periods when it is unable to invest significantly or at all in initial public offerings may be lower than during periods when the Fund is able to do so. Securities purchased in initial public offerings which are sold within 12 months after purchase may result in increased short-term capital gains, which will be taxable to the Fund’s shareholders as ordinary income. Certain “special situation” investments are investments in securities or other instruments that are determined to be illiquid or lacking a readily ascertainable fair value. Certain special situation investments prevent ownership interests therein from being withdrawn until the special situation investment, or a portion thereof, is realized or deemed realized, which may negatively impact Fund performance. Investing in special situations may have a magnified effect on the performance of funds with small amounts of assets.

Value Securities Risk. Value securities are securities of companies that may have experienced, for example, adverse business, industry or other developments or may be subject to special risks that have caused the securities to be out of favor and, in turn, potentially undervalued. The market value of a portfolio security may not meet portfolio management’s perceived value assessment of that security, or may decline in price, even though portfolio management believes the securities are already undervalued. There is also a risk that it may take longer than expected for the value of these investments to rise to portfolio management’s perceived value. In addition, value securities, at times, may not perform as well as growth securities or the stock market in general, and may be out of favor with investors for varying periods of time.

Additional Investment Strategies and Policies

This section describes certain investment strategies and policies that the Fund may utilize in pursuit of its investment objective and some additional factors and risks involved with investing in the Fund.

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Investment Guidelines

As a general matter, and except as specifically described in the discussion of the Fund's principal investment strategies in this prospectus or as otherwise required by the Investment Company Act of 1940, as amended (the 1940 Act), the rules and regulations thereunder and any applicable exemptive relief, whenever an investment policy or limitation states a percentage of the Fund's assets that may be invested in any security or other asset or sets forth a policy regarding an investment standard, compliance with that percentage limitation or standard will be determined solely at the time of the Fund's investment in the security or asset.

Holding Other Kinds of Investments

The Fund may hold other investments that are not part of its principal investment strategies. These investments and their risks are described below and/or in the SAI. The Fund may choose not to invest in certain securities described in this prospectus and in the SAI, although it has the ability to do so. Information on the Fund’s holdings can be found in the Fund’s shareholder reports or by visiting columbiathreadneedle.com/us.

Transactions in Derivatives

The Fund may enter into derivative transactions or otherwise have exposure to derivative transactions through underlying investments. Derivatives are financial contracts whose values are, for example, based on (or “derived” from) traditional securities (such as a stock or bond), assets (such as a commodity like gold or a foreign currency), reference rates (such as the London Interbank Offered Rate (commonly known as LIBOR)) or market indices (such as the Standard & Poor's (S&P) 500 ^® Index). The use of derivatives is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. Derivatives involve special risks and may result in losses or may limit the Fund's potential gain from favorable market movements. Derivative strategies often involve leverage, which may exaggerate a loss, potentially causing the Fund to lose more money than it would have lost had it invested in the underlying security or other asset directly. The values of derivatives may move in unexpected ways, especially in unusual market conditions, and may result in increased volatility in the value of the derivative and/or the Fund’s shares, among other consequences. The use of derivatives may also increase the amount of taxes payable by shareholders holding shares in a taxable account. Other risks arise from the Fund's potential inability to terminate or to sell derivative positions. A liquid secondary market may not always exist for the Fund's derivative positions at times when the Fund might wish to terminate or to sell such positions. Over-the-counter instruments (investments not traded on an exchange) may be illiquid, and transactions in derivatives traded in the over-the-counter market are subject to the risk that the other party will not meet its obligations. The use of derivatives also involves the risks of mispricing or improper valuation and that changes in the value of the derivative may not correlate perfectly with the underlying security, asset, reference rate or index. The Fund also may not be able to find a suitable derivative transaction counterparty, and thus may be unable to engage in derivative transactions when it is deemed favorable to do so, or at all. U.S. federal legislation has been enacted that provides for new clearing, margin, reporting and registration requirements for participants in the derivatives market. These changes could restrict and/or impose significant costs or other burdens upon the Fund’s participation in derivatives transactions. For more information on the risks of derivative investments and strategies, see the SAI.

Affiliated Fund Investing

The Investment Manager or an affiliate serves as investment adviser to funds using the Columbia brand (Columbia Funds), including those that are structured as “fund-of-funds”, and provides asset-allocation services to (i) shareholders by investing in shares of other Columbia Funds, which may include the Fund (collectively referred to in this section as Underlying Funds), and (ii) discretionary managed accounts (collectively referred to as affiliated products) that invest exclusively in Underlying Funds. These affiliated products, individually or collectively, may own a significant percentage of the outstanding shares of one or more Underlying Funds, and the Investment Manager seeks to balance potential conflicts of interest between the affiliated products and the Underlying Funds in which they invest. The affiliated products’ investment in the Underlying Funds may have the effect of creating economies of scale, possibly resulting in lower expense ratios for the Underlying Funds, because the affiliated products may own substantial portions of the shares of Underlying Funds. However, redemption of Underlying Fund shares by one or more affiliated products could cause the expense ratio of an Underlying Fund to increase, as its fixed costs would be

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spread over a smaller asset base. Because of large positions of certain affiliated products, the Underlying Funds may experience relatively large inflows and outflows of cash due to affiliated products’ purchases and sales of Underlying Fund shares. Although the Investment Manager or its affiliate may seek to minimize the impact of these transactions where possible, for example, by structuring them over a reasonable period of time or through other measures, Underlying Funds may experience increased expenses as they buy and sell portfolio securities to manage the cash flow effect related to these transactions. Further, when the Investment Manager or its affiliate structures transactions over a reasonable period of time in order to manage the potential impact of the buy and sell decisions for the affiliated products, those affiliated products, including funds-of-funds, may pay more or less (for purchase activity), or receive more or less (for redemption activity), for shares of the Underlying Funds than if the transactions were executed in one transaction. In addition, substantial redemptions by affiliated products within a short period of time could require the Underlying Fund to liquidate positions more rapidly than would otherwise be desirable, which may have the effect of reducing or eliminating potential gain or causing it to realize a loss. In order to meet such redemptions, an Underlying Fund may be forced to sell its liquid (or more liquid) positions, leaving the Underlying Fund holding, post-redemption, a relatively larger position in illiquid securities (securities that are not readily marketable or that cannot be sold or disposed of in the ordinary course of business, within seven days, at approximately the value at which the holder has valued the security) or less liquid securities. Substantial redemptions may also adversely affect the ability of the Underlying Fund to implement its investment strategy. The Investment Manager or its affiliate also has an economic conflict of interest in determining the allocation of affiliated products’ assets among the Underlying Funds, as it earns different fees from the various Underlying Funds.

Investing in Money Market Funds

The Fund may invest cash in, or hold as collateral for certain investments, shares of registered or unregistered money market funds, including funds advised by the Investment Manager or its affiliates. These funds are not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. The Fund and its shareholders indirectly bear a portion of the expenses of any money market fund or other fund in which the Fund may invest.

Lending of Portfolio Securities

The Fund may lend portfolio securities to broker-dealers or other financial intermediaries on a fully collateralized basis in order to earn additional income. The Fund may lose money from securities lending if, for example, it is delayed in or prevented from selling the collateral after the loan is made or recovering the securities loaned or if it incurs losses on the reinvestment of cash collateral.

The Fund currently does not participate in the securities lending program but the Board of Trustees (the Board) may determine to renew participation in the future. For more information on lending of portfolio securities and the risks involved, see the SAI and the annual and semiannual reports to shareholders.

Investing Defensively

The Fund may from time to time take temporary defensive investment positions that may be inconsistent with the Fund’s principal investment strategies in attempting to respond to adverse market, economic, political, social or other conditions, including, without limitation, investing some or all of its assets in money market instruments or shares of affiliated or unaffiliated money market funds or holding some or all of its assets in cash or cash equivalents. The Fund may take such defensive investment positions for as long a period as deemed necessary.

The Fund may not achieve its investment objective while it is investing defensively. Investing defensively may adversely affect Fund performance. During these times, the portfolio managers may make frequent portfolio holding changes, which could result in increased trading expenses and taxes, and decreased Fund performance. See also Investing in Money Market Funds above for more information.

Other Strategic and Investment Measures

The Fund may also from time to time take temporary portfolio positions that may or may not be consistent with the Fund’s principal investment strategies in attempting to respond to adverse market, economic, political, social or other conditions, including, without limitation, investing in derivatives, such as forward contracts, futures contracts,

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options, structured investments and swaps, for various purposes, including among others, investing in particular derivatives in seeking to reduce investment exposures, or in seeking to achieve indirect investment exposures, to a sector, country, region or currency where the Investment Manager believes such positioning is appropriate. The Fund may take such portfolio positions for as long a period as deemed necessary. While the Fund is so positioned, derivatives could comprise a substantial portion of the Fund’s investments and the Fund may not achieve its investment objective. Investing in this manner may adversely affect Fund performance. During these times, the portfolio managers may make frequent portfolio holding changes, which could result in increased trading expenses and taxes, and decreased Fund performance. For information on the risks of investing in derivatives, see Transactions in Derivatives above.

Portfolio Holdings Disclosure

The Board has adopted policies and procedures that govern the timing and circumstances of disclosure to shareholders and third parties of information regarding the securities owned by the Fund. A description of these policies and procedures is included in the SAI. Fund policy generally permits the disclosure of portfolio holdings information on the Fund's website (columbiathreadneedle.com/us) only after a certain amount of time has passed, as described in the SAI.

Purchases and sales of portfolio securities can take place at any time, so the portfolio holdings information available on the Fund's website may not always be current.

eDelivery and Mailings to Households

In order to reduce shareholder expenses, the Fund may, if prior consent has been provided, mail only one copy of the Fund’s prospectus and each annual and semiannual report to those addresses shared by two or more accounts. If you wish to receive separate copies of these documents, call 800.345.6611 or, if your shares are held through a financial intermediary, contact your intermediary directly. Additionally, you may elect to enroll in eDelivery to receive electronic versions of these documents by logging into your account at investor.columbiathreadneedle.com/us.

Cash Flows

The timing and magnitude of cash inflows from investors buying Fund shares could prevent the Fund from always being fully invested. Conversely, the timing and magnitude of cash outflows to shareholders redeeming Fund shares could require the Fund to sell portfolio securities at less than opportune times or to hold ready reserves of uninvested cash in amounts larger than might otherwise be the case to meet shareholder redemptions. Either situation could adversely impact the Fund’s performance.

Understanding Annual Fund Operating Expenses

The Fund’s annual operating expenses, as presented in the Annual Fund Operating Expenses table in the Fees and Expenses of the Fund section of this prospectus, generally are based on estimated expenses for the Fund’s current fiscal period, may vary by share class and are expressed as a percentage (expense ratio) of the Fund’s average net assets. The expense ratios reflect the Fund’s fee arrangements as of the date of this prospectus. In general, the Fund’s expense ratios will increase as its net assets decrease, such that the Fund’s actual expense ratios may be higher than the expense ratios presented in the Annual Fund Operating Expenses table if assets fall. Any commitment by the Investment Manager and/or its affiliates to waive fees and/or cap (reimburse) expenses is expected, in part, to limit the impact of any increase in the Fund’s expense ratios that would otherwise result because of a decrease in

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the Fund’s assets in the current fiscal period. The Fund’s annual operating expenses are comprised of (i) investment management fees, (ii) distribution and/or service fees, and (iii) other expenses. Management fees do not vary by class, but distribution and/or service fees and other expenses may vary by class.

Fee Waiver/Expense Reimbursement Arrangements

The Investment Manager and certain of its affiliates have contractually agreed to waive fees and/or reimburse expenses (excluding certain fees and expenses described below) through June 30, 2019, unless sooner terminated at the sole discretion of the Fund's Board, so that the Fund’s net operating expenses, after giving effect to fees waived/expenses reimbursed and any balance credits and/or overdraft charges from the Fund’s custodian, do not exceed the annual rates of:

    

Columbia Overseas Core Fund
Class A	1.28%
Class Adv	1.03%
Class C	2.03%
Class Inst	1.03%
Class Inst2	0.93%
Class Inst3	0.87%
Class R	1.53%

Under the agreement, the following fees and expenses are excluded from the Fund’s operating expenses when calculating the waiver/reimbursement commitment, and therefore will be paid by the Fund, if applicable: taxes (including foreign transaction taxes), expenses associated with investment in affiliated and non-affiliated pooled investment vehicles (including mutual funds and exchange-traded funds), transaction costs and brokerage commissions, costs related to any securities lending program, dividend expenses associated with securities sold short, inverse floater program fees and expenses, transaction charges and interest on borrowed money, interest, infrequent and/or unusual expenses and any other expenses the exclusion of which is specifically approved by the Fund’s Board. This agreement may be modified or amended only with approval from all parties.

Primary Service Providers

The Fund enters into contractual arrangements (Service Provider Contracts) with various service providers, including, among others, the Investment Manager, the Distributor, the Transfer Agent and the Fund’s custodian. The Fund’s Service Provider Contracts are solely among the parties thereto. Shareholders are not parties to, or intended to be third-party beneficiaries of, any Service Provider Contracts. Further, this prospectus, the SAI and any Service Provider Contracts are not intended to give rise to any agreement, duty, special relationship or other obligation between the Fund and any investor, or give rise to any contractual, tort or other rights in any individual shareholder, group of

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shareholders or other person, including any right to assert a fiduciary or other duty, enforce the Service Provider Contracts against the parties or to seek any remedy thereunder, either directly or on behalf of the Fund. Nothing in the previous sentence should be read to suggest any waiver of any rights under federal or state securities laws.

The Investment Manager, the Distributor, and the Transfer Agent are all affiliates of Ameriprise Financial, Inc. (Ameriprise Financial). They and their affiliates currently provide key services, including investment advisory, administration, distribution, shareholder servicing and transfer agency services, to the Fund and various other funds, including the Columbia Funds, and are paid for providing these services. These service relationships are described below.

The Investment Manager

Columbia Management Investment Advisers, LLC is located at 225 Franklin Street, Boston, MA 02110 and serves as investment adviser and administrator to the Columbia Funds. The Investment Manager is a registered investment adviser and a wholly-owned subsidiary of Ameriprise Financial. The Investment Manager’s management experience covers all major asset classes, including equity securities, debt instruments and money market instruments. In addition to serving as an investment adviser to traditional mutual funds, exchange-traded funds and closed-end funds, the Investment Manager acts as an investment adviser for itself, its affiliates, individuals, corporations, retirement plans, private investment companies and financial intermediaries.

Subject to oversight by the Board, the Investment Manager manages the day-to-day operations of the Fund, determining what securities and other investments the Fund should buy or sell and executing portfolio transactions. The Investment Manager may use the research and other capabilities of its affiliates and third parties in managing the Fund’s investments. The Investment Manager is also responsible for overseeing the administrative operations of the Fund, including the general supervision of the Fund’s operations, the coordination of the Fund’s other service providers and the provision of related clerical and administrative services.

The SEC has issued an order that permits the Investment Manager, subject to the approval of the Board, to appoint an unaffiliated subadviser or to change the terms of a subadvisory agreement, including fees paid thereunder, for the Fund without first obtaining shareholder approval, thereby avoiding the expense and delays typically associated with obtaining shareholder approval. The Investment Manager and the Columbia Funds have applied to amend this order. If issued, the updated order would permit the Investment Manager, subject to the approval of the Board, to appoint for the Fund not only unaffiliated subadvisers but also affiliated subadvisers without first obtaining shareholder approval. The Investment Manager and its affiliates may have other relationships, including significant financial relationships, with current or potential subadvisers or their affiliates, which may create certain conflicts of interest. When making recommendations to the Board to appoint or to change a subadviser, or to change the terms of a subadvisory agreement, the Investment Manager discloses to the Board the nature of any such material relationships. At present, the Investment Manager has not engaged any investment subadviser for the Fund.

The Fund pays the Investment Manager a fee for its management services, which include investment advisory services and administrative services. The fee is calculated as a percentage of the daily net assets of the Fund. The fee is paid monthly, as follows:

    

Annual Management Fee, as a % of Average Daily Net Assets:
Up to $500 million	0.870%
$500 million to $1 billion	0.820%
$1 billion to $1.5 billion	0.770%
$1.5 billion to $3 billion	0.720%
$3 billion to $6 billion	0.700%
$6 billion to $12 billion	0.680%
Over $12 billion	0.670%

A discussion regarding the basis for the Board approving the adoption of the Fund's management agreement will be available in the Fund’s semiannual report to shareholders for the fiscal period ended August 31, 2018.

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Conflicts of interest and limitations that could affect a Columbia Fund may arise from, for example, the following:

■	compensation and other benefits received by the Investment Manager and other Ameriprise Financial affiliates related to the management/administration of a Columbia Fund and the sale of its shares;

■	the allocation of, and competition for, investment opportunities among the Fund, other funds and accounts advised/managed by the Investment Manager and other Ameriprise Financial affiliates, or Ameriprise Financial itself and its affiliates;

■	separate and potentially divergent management of a Columbia Fund and other funds and accounts advised/managed by the Investment Manager and other Ameriprise Financial affiliates;

■	regulatory and other investment restrictions on investment activities of the Investment Manager and other Ameriprise Financial affiliates and accounts advised/managed by them;

■	insurance and other relationships of Ameriprise Financial affiliates with companies and other entities in which a Columbia Fund invests; and

■	regulatory and other restrictions relating to the sharing of information between Ameriprise Financial and its affiliates, including the Investment Manager, and a Columbia Fund.

The Investment Manager and Ameriprise Financial have adopted various policies and procedures that are intended to identify, monitor and address conflicts of interest. However, there is no assurance that these policies, procedures and disclosures will be effective.

Additional information about Ameriprise Financial and the types of conflicts of interest and other matters referenced above is set forth in the Investment Management and Other Services — Other Roles and Relationships of Ameriprise Financial and its Affiliates — Certain Conflicts of Interest section of the SAI. Investors in the Columbia Funds should carefully review these disclosures and consult with their financial advisor if they have any questions.

Certain Legal Matters

Ameriprise Financial and certain of its affiliates have historically been involved in a number of legal, arbitration and regulatory proceedings, including routine litigation, class actions and governmental actions, concerning matters arising in connection with the conduct of their business activities. Ameriprise Financial believes that the Fund is not currently the subject of, and that neither Ameriprise Financial nor any of its affiliates are the subject of, any pending legal, arbitration or regulatory proceedings that are likely to have a material adverse effect on the Fund or the ability of Ameriprise Financial or its affiliates to perform under their contracts with the Fund. Information regarding certain pending and settled legal proceedings may be found in the Fund’s shareholder reports and in the SAI. Additionally, Ameriprise Financial is required to make quarterly (10-Q), annual (10-K) and, as necessary, 8-K filings with the SEC on legal and regulatory matters that relate to Ameriprise Financial and its affiliates. Copies of these filings may be obtained by accessing the SEC website at sec.gov.

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The Funds

The Columbia Funds (referred to as the Funds) generally share the same policies and procedures for investor services, as described below. Each Fund is a series of Columbia Funds Series Trust (CFST), Columbia Funds Series Trust I (CFST I) or Columbia Funds Series Trust II (CFST II), and certain features of distribution and/or service plans may differ among these trusts. The Fund offered by this prospectus is a series of CFST II. Columbia Funds with names that include the words “Tax-Exempt,” “Municipal” or “Muni” (the Tax-Exempt Funds) have certain policies that differ from other Columbia Funds (the Taxable Funds). The Fund offered by this prospectus is treated as a Taxable Fund for these purposes.

Funds Contact Information

Additional information about the Funds, including sales charges and other class features and policies, can be obtained, free of charge, at columbiathreadneedle.com/us,* by calling toll-free 800.345.6611, or by writing (regular mail) to Columbia Management Investment Services Corp., P.O. Box 8081, Boston, MA 02266-8081 or (express mail) Columbia Management Investment Services Corp., c/o DST Asset Manager Solutions, Inc., 30 Dan Road, Suite 8081, Canton, MA 02021-2809.

*The website references in this prospectus are inactive links and information contained in or otherwise accessible through the referenced websites does not form a part of this prospectus.

Summary of Share Class Features

Each share class has its own investment eligibility criteria, cost structure and other features. You may not be eligible to invest in every share class. Your financial intermediary may not make every share class available or may cease to make available one or more share classes of the Fund. The share class you select through your financial intermediary may have higher fees and/or sales charges than other classes of shares available through other financial intermediaries. An investor transacting in a class of Fund shares without any front-end sales charge, contingent deferred sales charge (CDSC), or other asset-based fee for sales or distribution, such as a Rule 12b-1

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Choosing a Share Class (continued)

fee, may be required to pay a commission to the financial intermediary for effecting such transactions. Each investor’s personal situation is different and you may wish to discuss with your financial intermediary the share classes the Fund offers, which share classes are available to you and which share class(es) is/are appropriate for you. In all instances, it is your responsibility to notify your financial intermediary or (for Direct-at-Fund Accounts, as defined below) the Fund at the time of purchase of any relationship or other facts that may qualify you for sales charge waivers or discounts. The Fund, the Distributor and the Transfer Agent do not provide investment advice or make recommendations regarding Fund share classes. Your financial intermediary may provide advice and recommendations to you, such as which share class(es) is/are appropriate for you.

When deciding which class of shares to buy, you should consider, among other things:

■	The amount you plan to invest.

■	How long you intend to remain invested in the Fund.

■	The fees (e.g., sales charge or “load”) and expenses for each share class.

■	Whether you may be eligible for a reduction or waiver of sales charges when you buy or sell shares.

■	The net asset value (NAV) per share is the price of a share calculated by the Fund every business day.
■	The offering price per share is the NAV per share plus any front-end sales charge (or load) that applies.

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Share Class Features

The following summarizes the primary features of Class A, Class Adv, Class C, Class Inst, Class Inst2, Class Inst3, Class K, Class R, Class T and Class V shares.

Not all Funds offer every class of shares. The Fund offers the class(es) of shares set forth on the cover of this prospectus and may offer other share classes through a separate prospectus. Although certain share classes are generally closed to new and/or existing investors, information relating to these share classes is included in the table below because certain qualifying purchase orders are permitted, as described below.

The sales charge reductions and waivers available to investors who purchase and hold their Fund shares through different financial intermediaries may vary. Appendix A describes financial intermediary-specific reductions and/or waiver policies. A shareholder transacting in Fund shares through a financial intermediary identified in Appendix A should carefully read the terms and conditions of Appendix A . A reduction and/or waiver that is specific to a particular financial intermediary is not available to Direct-at-Fund Accounts, as defined below, or through another financial intermediary. The information in Appendix A may be provided by, or compiled from or based on information provided by the financial intermediaries identified in Appendix A . The Fund, the Investment Manager and the Distributor do not establish financial intermediary-specific policies and are not responsible for ensuring that you receive any discounts or waivers that may be available to you in this regard. Please consult your financial intermediary with respect to any sales charge reduction and/or waiver described in Appendix A .

A Note About Class T Shares

Class T shares are sold only through financial intermediaries that, by written agreement with the Distributor, are specifically authorized to sell Class T shares (Class T Intermediaries).

Class T shares are capable of being offered by different financial intermediaries with different front-end sales charge structures. Currently, Class T shares are offered with only one sales charge structure, which means that all Class T Intermediaries that are offering Class T shares are doing so with the same pricing. For convenience, these Class T Intermediaries are referred to as Category One Financial Intermediaries . Financial intermediaries may in the future seek to offer Class T shares under a different pricing structure and, as such, other categories of Class T Intermediaries may be added in the future. Note also that, unlike other classes of shares of the Fund with a front-end sales charge (i.e., Class A and Class V shares, as available), the front-end sales charge applicable to Class T shares is a per-transaction charge, meaning that separate orders will not be aggregated for purposes of calculating the rate of the sales charge payable. Discounts are not available for Class T shares (for example, under a right of accumulation, letter of intent or other such programs).

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(e)

For Columbia Short Term Municipal Bond Fund, a CDSC of 0.50% is charged on certain investments of $500,000 or more redeemed within 12 months after purchase. The following Funds are not subject to a front-end sales charge or a CDSC on Class A shares: Columbia Government Money Market Fund, Columbia Large Cap Enhanced Core Fund, Columbia Large Cap Index Fund, Columbia Mid Cap Index Fund, Columbia Small Cap Index Fund and Columbia U.S. Treasury Index Fund.

(f)	If you are eligible to invest in Class A shares without a front-end sales charge, you should discuss your options with your financial intermediary. For more information, see Choosing a Share Class – Reductions/Waivers of Sales Charges.

(g)	There is no CDSC on redemptions from Class C shares of Columbia Government Money Market Fund.

(h)	These share classes are closed to new accounts, or closed to previously eligible investors, subject to certain conditions, as summarized below and described in more detail under Buying, Selling and Exchanging Shares — Buying Shares — Eligible Investors:

•   Class Inst Shares . Financial intermediaries that clear Fund share transactions through designated financial intermediaries and their mutual fund trading platforms that have been given specific written notice from the Transfer Agent, effective March 29, 2013, of the termination of their eligibility for new purchases of Class Inst shares and omnibus retirement plans are not permitted to establish new Class Inst accounts, subject to certain exceptions. Omnibus retirement plans that opened and, subject to exceptions, funded a Class Inst account as of close of business on March 28, 2013, and have continuously held Class Inst shares in such account after such date, may generally continue to make additional purchases of Class Inst shares, open new Class Inst accounts and add new participants. In certain circumstances and in the sole discretion of the Distributor, omnibus retirement plans affiliated with a grandfathered plan may also open new Class Inst accounts. Accounts of financial intermediaries (other than omnibus retirement plans) that clear Fund share transactions for their client or customer accounts through designated financial intermediaries and their mutual fund trading platforms are not permitted to establish new Class Inst accounts or make additional purchases of Class Inst shares (other than through Fund distribution reinvestments).

•   Class Inst2 Shares . Shareholders with Class Inst2 accounts funded before November 8, 2012 who do not satisfy the current eligibility criteria for Class Inst2 shares may not establish new Class Inst2 accounts but may continue to make additional purchases of Class Inst2 shares in existing accounts. In addition, investment advisory programs and similar programs that opened a Class Inst2 account as of May 1, 2010, and continuously hold Class Inst2 shares in such account after such date, may generally not only continue to make additional purchases of Class Inst2 shares but also open new Class Inst2 accounts and add new shareholders in the program.

•   Class Inst3 Shares . Shareholders with Class Inst3 accounts funded before November 8, 2012 who do not satisfy the current eligibility criteria for Class Inst3 shares may not establish new accounts for such share class but may continue to make additional purchases of Class Inst3 shares in existing accounts.

•   Class K Shares . Shareholders who opened and funded a Class K account with a Fund as of the close of business on December 31, 2010 may continue to make additional purchases of such share class, and existing Class K accounts may continue to allow new investors or participants to be established in their Fund account.

•   Class V Shares. Shareholders   with Class V accounts who received, and have continuously held, Class V shares (formerly named Class T shares, which have no relation to the Fund’s current Class T shares) in connection with the merger of certain Galaxy funds into certain Funds that were then named Liberty funds may continue to make additional purchases of such share class.

Sales Charges and Commissions

Sales charges, commissions, and distribution fees compensate financial intermediaries (typically your financial advisor) for selling shares to you, and service fees compensate financial intermediaries for maintaining and servicing the shares held in your account with them. Distribution and service fees are discussed in a separate sub-section below. Depending on which share class you choose and the financial intermediary through which you purchase your shares, you may pay these charges at potentially different levels at the outset as a front-end sales charge, at the time you sell your shares as a CDSC and/or over time in the form of distribution and/or service fees.

As described in more detail below, Class A, Class T and Class V shares have a front-end sales charge, which is deducted from your purchase price when you buy your shares, and results in a smaller dollar amount being invested in the Fund than the purchase price you pay (unless you qualify for a waiver or (Class A shares and Class V shares only) reduction of the sales charge). The Fund’s other share classes do not have a front-end sales charge, so the full amount of your purchase price is invested in those classes. Class A shares have lower ongoing distribution and/or service fees than Class C and Class R shares of the Fund. Over time, Class C and Class R shares can incur distribution and/or service fees that are equal to or more than the front-end sales charge and the distribution and/or service fees you would pay for Class A shares. Thus, although the full amount of your purchase price of Class C and Class R shares is invested in a Fund, your return on this money will be reduced by the expected higher annual expenses of Class C and Class R shares. Class Adv, Class Inst, Class Inst2 and Class Inst3 shares of the Fund do not have distribution and/or service fees.

Whether the ultimate cost is higher for one class over another depends on the amount you invest, how long you hold your shares, the amount of the sales charges, and whether you are eligible for reduced or waived sales charges, if available. The differential between classes also will vary depending on the actual investment return for any given investment period. You are responsible for choosing the share class most appropriate for you after taking into

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Choosing a Share Class (continued)

account your share class eligibility, class-specific features, and any applicable reductions in, or waivers of, sales charges. For more information, see Choosing a Share Class – Reductions/Waivers of Sales Charges . We encourage you to consult with a financial advisor who can help you with your investment decisions. Please contact your financial intermediary for more information about services, fees and expenses, and other important information about investing in the Fund, as well as with any questions you may have about your investing options. In all instances, it is your responsibility to notify your financial intermediary or (for Direct-at-Fund Accounts, as defined below) the Fund at the time of purchase of any relationship or other facts that may qualify you for sales charge waivers or discounts.

Class A Shares — Front-End Sales Charge

Unless your purchase qualifies for a waiver (e.g., you buy the shares through reinvested Fund distributions or subject to an applicable financial intermediary-specific waiver), you will pay a front-end sales charge when you buy Class A shares (other than shares of Columbia Government Money Market Fund, Columbia Large Cap Enhanced Core Fund, Columbia Large Cap Index Fund, Columbia Mid Cap Index Fund, Columbia Small Cap Index Fund and Columbia U.S. Treasury Index Fund), resulting in a smaller dollar amount being invested in a Fund than the purchase price you pay. For more information about sales charge waivers and reduction opportunities, see Choosing a Share Class — Reductions/Waivers of Sales Charges and Appendix A.

The Distributor receives the sales charge and re-allows (or pays) a portion of the sales charge to the financial intermediary through which you purchased the shares. The Distributor retains the balance of the sales charge. The Distributor retains the full sales charge you pay when you purchase shares of the Fund directly from the Fund (through the Transfer Agent, rather than through a financial intermediary).

The front-end sales charge you will pay on Class A shares:

■	depends on the amount you are investing (generally, the larger the investment, the smaller the percentage sales charge), and

■	is based on the total amount of your purchase and the value of your account (and any other accounts eligible for aggregation of which you or your financial intermediary notifies the Fund).

The table below presents the front-end sales charge as a percentage of both the offering price and the net amount invested.

    

Class A Shares — Front-End Sales Charge — Breakpoint Schedule*
Breakpoint Schedule For:	Dollar amount of shares bought (a)	Sales charge as a % of the offering price (b)	Sales charge as a % of the net amount invested (b)	Amount retained by or paid to financial intermediaries as a % of the offering price
Equity Funds, Columbia Adaptive Risk Allocation Fund, Columbia Alternative Beta Fund, Columbia Commodity Strategy Fund, Columbia Diversified Absolute Return Fund and Funds-of-Funds (equity)*	$ 0–$49,999	5.75%	6.10%	5.00%
	$ 50,000–$99,999	4.50%	4.71%	3.75%
	$100,000–$249,999	3.50%	3.63%	3.00%
	$250,000–$499,999	2.50%	2.56%	2.15%
	$500,000–$999,999	2.00%	2.04%	1.75%
	$ 1,000,000 or more	0.00%	0.00%	0.00% (c)

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Class A Shares — CDSC

In some cases, you'll pay a CDSC if you sell Class A shares that you purchased without a front-end sales charge.

Tax-Exempt Funds

■

If you purchased Class A shares of any Tax-Exempt Fund (other than Columbia Short Term Municipal Bond Fund and Columbia U.S. Social Bond Fund) without paying a front-end sales charge because your eligible accounts aggregated $500,000 or more at the time of purchase, you will incur a CDSC of 0.75% if you redeem those shares within 12 months after purchase. Subsequent Class A share purchases that bring your aggregate account value to $500,000 or more will also be subject to a CDSC of 0.75% if you redeem those shares within 12 months after purchase.

■

If you purchased Class A shares of Columbia Short Term Municipal Bond Fund without paying a front-end sales charge because your eligible accounts aggregated $500,000 or more at the time of purchase, you will incur a CDSC of 0.50% if you redeem those shares within 12 months after purchase. Subsequent Class A share purchases that bring your aggregate account value to $500,000 or more will also be subject to a CDSC of 0.50% if you redeem those shares within 12 months after purchase.

■

If you purchased Class A shares of Columbia U.S. Social Bond Fund on or after August 8, 2016 without paying a front-end sales charge because your eligible accounts aggregated $500,000 or more at the time of purchase, you will incur a CDSC of 0.75% if you redeem those shares within 12 months after purchase. Subsequent Class A share purchases made on or after August 8, 2016 that bring your aggregate account value to $500,000 or more will also be subject to a CDSC of 0.75% if you redeem those shares within 12 months after purchase. If you purchased Class A shares of Columbia U.S. Social Bond Fund prior to August 8, 2016 without paying a front-end sales charge because your eligible accounts aggregated between $1 million and $50 million at the time of purchase, you will incur a CDSC if you redeem those shares within 18 months after purchase, which is charged as follows: 1.00% CDSC if shares are redeemed within 12 months after purchase; and 0.50% CDSC if shares are redeemed more than 12, but less than 18, months after purchase. Subsequent Class A share purchases made prior to August 8, 2016 that bring your aggregate account value to $1 million or more (but less than $50 million) will also be subject to a CDSC if you redeem them within 18 months after purchase as described in this paragraph.

Taxable Funds

■

If you purchased Class A shares of any Taxable Fund without paying a front-end sales charge because your eligible accounts aggregated between $1 million and $50 million at the time of purchase, you will incur a CDSC if you redeem those shares within 18 months after purchase, which is charged as follows: 1.00% CDSC if shares are redeemed within 12 months after purchase; and 0.50% CDSC if shares are redeemed more than 12, but less than 18, months after purchase. Subsequent Class A share purchases that bring your aggregate account value to $1 million or more (but less than $50 million) will also be subject to a CDSC if you redeem them within 18 months after purchase as described in the previous sentence.

Class A Shares — Commissions

The Distributor may pay your financial intermediary an up-front commission when you buy Class A shares. The Distributor generally funds the commission through the applicable sales charge paid by you. For more information, see Class A Shares — Front-End Sales Charge above .

The Distributor may also pay your financial intermediary a cumulative commission when you buy Class A shares in amounts not subject to a front-end sales charge, according to the following schedule:

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are offering Class T shares (Class T Intermediaries) are offering the same pricing. For convenience, these Class T Intermediaries are referred to as Category One Financial Intermediaries. Financial intermediaries may seek to offer Class T shares under a different pricing structure and, as a result, other categories of Class T Intermediaries may be added in the future.

The front-end sales charge applicable to Class T shares is a per-transaction charge, meaning that the separate orders will not be aggregated for purposes of calculating the rate of the sales charge payable, which is different from other Fund share classes with a front-end sales charge. Unless your purchase qualifies for a waiver, you will pay a front-end sales charge on each purchase of Class T shares based on the amount of each purchase transaction. As with all front-end sales charges, this will result in a smaller dollar amount being invested in the Fund than the purchase price you pay. No discounts (for example, under a right of accumulation, letter of intent, or other such programs) are available for Class T shares. For information about sales charge waivers, see Choosing a Share Class — Reductions/Waivers — Class T Sales Charge Waivers below.

    

Class T Shares — Front-End Sales Charge (Per Transaction)
Breakpoint Schedule For:	Dollar amount of shares bought	Sales charge as a % of the offering price (a)	Sales charge as a % of the net amount invested (a)	Amount retained by or paid to Financial Intermediaries as a % of the offering price
Class T Shares (Purchasing through a Category One Financial Intermediary)	$ 0–$249,999	2.50%	2.56%	2.50%
	$250,000–$499,999	2.00%	2.04%	2.00%
	$500,000–$999,999	1.50%	1.53%	1.50%
	$ 1,000,000 or more	1.00%	1.01%	1.00%

(a)

Because the offering price is calculated to two decimal places, the dollar amount of the sales charge as a percentage of the offering price and your net amount invested for any particular purchase of Fund shares may be higher or lower depending on whether downward or upward rounding was required during the calculation process. Purchase price includes the sales charge.

Class V Shares — Front-End Sales Charge

Unless you qualify for a waiver (e.g., you purchase shares through reinvested Fund distributions), you will pay a front-end sales charge when you buy Class V shares, resulting in a smaller dollar amount being invested in a Fund than the purchase price you pay. For more information about sales charge waivers (as well as sales charge reduction opportunities), see Choosing a Share Class — Reductions/Waivers of Sales Charges.

The front-end sales charge you will pay on Class V shares:

■	depends on the amount you are investing (generally, the larger the investment, the smaller the percentage sales charge), and

■	is based on the total amount of your purchase and the value of your account (and any other accounts eligible for aggregation of which you notify your financial intermediary or, in the case of Direct-at-Fund Accounts (as defined below), you notify the Fund).

    

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Choosing a Share Class (continued)

including accounts maintained through different financial intermediaries. You and your financial intermediary are responsible for ensuring that you receive discounts for which you are eligible. The Fund is not responsible for a financial intermediary's failure to apply the eligible discount to your account. You may be asked by your financial intermediary (or by the Fund if you hold your account directly with the Fund) for account statements or other records to verify your discount eligibility for new and subsequent purchases, including, when applicable, records for accounts opened with a different financial intermediary and records of accounts established by members of your immediate family.

The sales charge reductions available to investors who purchase and hold their Fund shares through different financial intermediaries may vary. For a description of such financial intermediary-specific sales charge reductions, see Appendix A .

Eligible Accounts

The following accounts are eligible for account value aggregation as described above, provided that they are invested in Class A, Class C, Class E, Class Inst or Class V shares of a Fund, or non-retirement plan accounts invested in Class Adv or Class Inst2 shares of a Fund: individual or joint accounts; Roth and traditional Individual Retirement Accounts (IRAs); Simplified Employee Pension accounts (SEPs), Savings Investment Match Plans for Employees of Small Employers accounts (SIMPLEs) and Tax Sheltered Custodial Accounts (TSCAs); Uniform Gifts to Minors Act (UGMA)/Uniform Transfers to Minors Act (UTMA) accounts for which you, your spouse, or your domestic partner is parent or guardian of the minor child; revocable trust accounts for which you or an immediate family member, individually, is the beneficial owner/grantor; accounts held in the name of your, your spouse’s, or your domestic partner’s sole proprietorship or single owner limited liability company or S corporation; qualified retirement plan assets, provided that you are the sole owner of the business sponsoring the plan, are the sole participant (other than a spouse) in the plan, and have no intention of adding participants to the plan; and investments in wrap accounts.

The following accounts are not eligible for account value aggregation as described above: accounts of pension and retirement plans with multiple participants, such as 401(k) plans (which are combined to reduce the sales charge for the entire pension or retirement plan and therefore are not used to reduce the sales charge for your individual accounts); investments in 529 plans, donor advised funds, variable annuities, variable insurance products or managed separate accounts; charitable and irrevocable trust accounts; accounts holding shares of money market funds that used the Columbia brand before May 1, 2010; accounts invested in Class Inst3, Class K, Class R or Class T shares of a Fund; and retirement plan accounts invested in Class Adv or Class Inst2 shares of a Fund.

Additionally, direct purchases of shares of Columbia Government Money Market Fund may not be aggregated for account value aggregation purposes; however, shares of Columbia Government Money Market Fund acquired by exchange from other Funds may be included in account value aggregation.

Class A and Class V Shares Front-End Sales Charge Waivers

There are no front-end sales charges on reinvested Fund distributions. The Distributor may waive front-end sales charges on purchases of Class A and Class V shares of the Funds by certain categories of investors, including Board members, certain employees of financial intermediaries, Fund portfolio managers, certain partners and employees of outside legal counsel to the funds or the Board, separate accounts of an insurance company exempt from

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registration under Section 3(c)(11), registered broker-dealer firms that have an agreement with the Distributor purchasing fund shares for their investment account only, and qualified employee benefit plan rollovers to Class A shares in the same Fund (see the SAI’s Appendix S for details). For a more complete description of categories of investors who may purchase Class A and Class V shares of the Funds at NAV, without payment of any front-end sales charge that would otherwise apply, see Appendix S to the SAI.

In addition, certain types of purchases of Class A and Class V shares may be made at NAV. The Distributor may waive front-end sales charges on (i) purchases (including exchanges) of Class A shares in accounts of financial intermediaries that have entered into agreements with the Distributor to offer Fund shares to self-directed investment brokerage accounts that may or may not charge a transaction fee to customers; (ii) exchanges of Class Inst shares of a Fund for Class A shares of the Fund; (iii) purchases of Class A shares on brokerage mutual fund-only platforms of financial intermediaries that have an agreement with the Distributor that specifically authorizes the offering of Class A shares within such platform; (iv) purchases through certain wrap fee or other products or programs that involve fee-based compensation arrangements that have, or clear trades through a financial intermediary that has, a selling agreement with the Distributor; (v) purchases through state sponsored 529 Plans; (vi) purchases through banks, trust companies, and thrift institutions acting as fiduciaries; and (vii) purchases through certain employee benefit plans and certain qualified deferred compensation plans. For a more complete description of these eligible transactions, see Appendix S to the SAI.

The sales charge waivers available to investors who purchase and hold their Fund shares through different financial intermediaries may vary. For a description of such financial intermediary-specific sales charge waivers, see Appendix A .

Class T Sales Charge Waivers

There is no front-end sales charge on (i) reinvested Fund distributions; (ii) exchanges of Class T shares of the Fund from, at the discretion of Class T Intermediaries, another class of shares of the same Fund held in accounts of Class T Intermediaries, provided that (a) the other share class may only be exchanged for Class T shares if your financial intermediary does not offer that other share class on the financial intermediary’s commission-based platform and (b), unless waived in the Distributor’s discretion, shares of the class to be exchanged are held in a networked or omnibus account with the Fund; and (iii) purchases within fee-based accounts, provided that the Class T Intermediary has an agreement with the Distributor that specifically contemplates offering Class T shares within the designated fee-based platform.

The sales charge waivers available to investors who purchase and hold their Fund shares through different financial intermediaries may vary. For a description of such financial intermediary-specific sales charge waivers, see Appendix A .

CDSC Waivers – Class A, Class C and Class V

You may be able to avoid an otherwise applicable CDSC when you sell Class A, Class C or Class V shares of the Fund. This could happen because of the way in which you originally invested in the Fund, because of your relationship with the Funds or for other reasons. For example, the CDSC will be waived on redemptions of shares in the event of the shareholder's death; that result from required minimum distributions taken from retirement accounts when the shareholder reaches age 70½; in connection with the Fund's Small Account Policy (which is described in Buying, Selling and Exchanging Shares — Transaction Rules and Policies ); and by certain other investors and in certain other types of transactions or situations. For a more complete description of the available waivers of the CDSC on redemptions of Class A, Class C or Class V shares, see Appendix S to the SAI.

The sales charge waivers available to investors who purchase and hold their Fund shares through different financial intermediaries may vary. For a description of such financial intermediary-specific sales charge waivers, see Appendix A .

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Repurchases (Reinstatements)

As noted in the table below, you can redeem shares of certain classes (see Redeemed Share Class below) and use such redemption proceeds to buy shares of the Corresponding Repurchase Class without paying an otherwise applicable sales charge and/or CDSC (other than redemptions from Columbia Government Money Market Fund unless purchased via an exchange from another Fund) within 90 days, up to the amount of the redemption proceeds.

    

Any CDSC paid upon redemption of your Class A, Class C or Class V shares of a Fund will not be reimbursed.

To be eligible for the repurchase (or reinstatement) privilege, the purchase must be made into an account for the same owner, but does not need to be into the same Fund from which the shares were sold. The Transfer Agent, Distributor or their agents must receive a written reinstatement request from you or your financial intermediary within 90 days after the shares are redeemed. The purchase of the Corresponding Repurchase Class (as noted in the table above) through this repurchase (or reinstatement) privilege will be made at the NAV of such shares next calculated after the request is received in “good form.” Systematic withdrawals and purchases are excluded from this policy.

Restrictions and Changes in Terms and Conditions

Restrictions may apply to certain accounts and certain transactions. The Funds and/or the Distributor may change or cancel these terms and conditions at any time. Unless you provide your financial intermediary with information in writing about all of the factors that may count toward available reductions or waivers of an applicable sales charge, there can be no assurance that you will receive all of the reductions and waivers for which you may be eligible. To the extent your Fund account is held directly with the Fund, you should provide this information to the Fund when placing your purchase or redemption order. Please see Appendix A to this prospectus and Appendix S of the SAI for more information about sales charge waivers.

Distribution and Service Fees

The Board has approved, and the Funds have adopted, distribution and/or shareholder service plans which set the distribution and/or service fees that are periodically deducted from the Funds’ assets. These fees are calculated daily, may vary by share class and are intended to compensate the Distributor and/or eligible financial intermediaries for, with regard to distribution fees, selling Fund shares and, with regard to service fees, directly or indirectly providing services to shareholders. Because the fees are paid out of the Fund's assets on an ongoing basis, they will increase the cost of your investment over time.

The table below shows the maximum annual distribution and/or service fees (as an annual percentage of average daily net assets) and the combined amount of such fees applicable to each share class:

    

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