Additional Information About the Fund

Additional information about the Fund’s investments will be available in the Fund’s annual and semiannual reports to shareholders. In the annual report, you will find a discussion of the market conditions and investment strategies that significantly affected the Fund’s performance during its last fiscal year. The SAI also provides additional information about the Fund and its policies. The SAI, which has been filed with the SEC, is legally part of this prospectus (incorporated by reference). To obtain these documents free of charge, to request other information about the Fund and to make shareholder inquiries contact Columbia Funds as follows:

By Mail:   Columbia Funds
c/o Columbia Management Investment Services Corp.
P.O. Box 8081
Boston, MA 02266-8081

By Telephone: 800.345.6611

Online: columbiamanagement.com

Information Provided by the SEC

You can review and copy information about the Fund (including this prospectus, the SAI and shareholder reports when available) at the SEC’s Public Reference Room in Washington, D.C. To find out more about the operation of the Public Reference Room, call the SEC at 202.551.8090. Reports and other information about the Fund are also available in the EDGAR Database on the SEC’s website at http://www.sec.gov. You can receive copies of this information, for a fee, by electronic request at the following e-mail address: publicinfo@sec.gov or by writing the Public Reference Section, Securities and Exchange Commission, Washington, D.C. 20549-1520.

The investment company registration number of Columbia Funds Series Trust I, of which the Fund is a series, is 811-04367.

© 2015 Columbia Management Investment Distributors, Inc.
225 Franklin Street, Boston, MA 02110
800.345.6611

PRO259_05_D01_(01/15)

The Securities and Exchange Commission (SEC) and the Commodity Futures Trading Commission (CFTC) have not approved or disapproved these securities or passed upon the adequacy of this prospectus. Any representation to the contrary is a criminal offense.

Columbia Diversified Absolute Return Fund

Table of Contents

Summary of the Fund	3
Investment Objective	3
Fees and Expenses of the Fund	3
Principal Investment Strategies	4
Principal Risks	5
Performance Information	12
Fund Management	12
Purchase and Sale of Fund Shares	12
Tax Information	13
Payments to Broker-Dealers and Other Financial Intermediaries	13
More Information About the Fund	14
Investment Objective	14
Principal Investment Strategies	14
Principal Risks	16
Additional Investment Strategies and Policies	26
Primary Service Providers	29
Other Roles and Relationships of Ameriprise Financial and its Affiliates — Certain Conflicts of Interest	32
Certain Legal Matters	33
About the Fund’s Wholly-Owned Subsidiary	33
Choosing a Share Class	34
The Funds	34
Summary of Share Class Features	34
Sales Charges and Commissions	38
Reductions/Waivers of Sales Charges	45
Distribution and Service Fees	47
Selling Agent Compensation	50
Buying, Selling and Exchanging Shares	51
Share Price Determination	51
Transaction Rules and Policies	52
Opening an Account and Placing Orders	56
Buying Shares	58
Selling Shares	63
Exchanging Shares	64
Distributions and Taxes	67
Distributions to Shareholders	67
Taxes	68
Financial Highlights	70

2	Prospectus 2015

Columbia Diversified Absolute Return Fund

Summary of the Fund

Columbia Diversified Absolute Return Fund

Summary of the Fund (continued)

The following example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example illustrates the hypothetical expenses that you would incur over the time periods indicated, and assumes that:

■	you invest $10,000 in the applicable class of Fund shares for the periods indicated,
■	your investment has a 5% return each year, and
■	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

The Fund pursues absolute (positive) returns through a diversified portfolio reflecting multiple asset classes and various investment and hedging strategies employed across equity, fixed income and other markets, such as commodities markets, while seeking to capitalize on market inefficiencies.

Although the specific strategies the Fund pursues and the manner in which the Fund pursues such strategies may change from time to time, the Fund is currently expected to combine tactical beta, alternative beta and alpha strategies in seeking the Fund’s investment objective. (In general, beta is a measure of price volatility resulting from general market movements and alpha is a measure of return resulting from active management.) The Fund’s investment manager, Columbia Management Investment Advisers, LLC (Columbia Management or the Investment Manager) may use fundamental and quantitative methods to identify and capitalize on short-term mispricings within and across traditional asset classes and markets, such as stocks and bonds. This strategy may be referred to as a tactical beta strategy in that it seeks opportunities to earn returns from price movements of broad markets. For instance, if the Investment Manager believes the U.S. equity market is undervalued, the Investment Manager may seek to capitalize on this mispricing by investing in futures on a U.S. equities index. The Investment Manager may also use fundamental and quantitative methods to identify and capitalize on systemic and structural market inefficiencies. This strategy may be referred to as an alternative beta strategy in that it seeks to generate returns with relatively low correlation to overall market movements by employing a systematic, rules-based based approach. For instance, the Fund may take a long position in a broad basket of equities that the Investment Manager believes are attractively valued and take a short position in a broad basket of equities that the Investment Manager believes are unattractively valued, in order to generate returns from the relative price difference generally expected in the equity markets over time between undervalued and overvalued equities (i.e., the “value

4	Prospectus 2015

Columbia Diversified Absolute Return Fund

Summary of the Fund (continued)

premium”). The Investment Manager will also allocate assets to long, short and other strategies intended to generate returns that are not dependent on overall market direction. These strategies may be referred to as alpha strategies in that they are intended to have relatively low correlation to market movements and are derived from active management.

The Fund’s investments and strategies are expected to employ both long and short positions in foreign and domestic equities (including common stock, preferred stock and convertible securities), equity futures, index futures, options, swaps, fixed-income, floating rate and other debt securities (including U.S. government obligations, sovereign and quasi-sovereign debt obligations, asset-backed securities, exchange traded notes, mortgage-backed securities and fixed income futures), currency forwards and futures and other commodity-related investments, and other investment companies (including mutual funds, closed-end funds and exchange-traded funds (ETFs)). The Fund may gain investment exposure to these securities and instruments directly or indirectly through investment in one or more Subsidiaries (as defined below) or affiliated and third party investment companies

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

The Fund may invest without limit in foreign investments (including currencies), which may include investments in emerging markets, and in investments that are rated below investment-grade or, if unrated, deemed to be of comparable quality (commonly referred to as “high yield securities” or “junk bonds”).

The Fund may invest in derivatives such as futures (including bond, currency, equity index, interest rate and volatility index futures), forward foreign currency contracts, forward interest rate agreements, options and swap contracts (including credit default swaps, interest rate swaps and total return swaps), in an effort to produce incremental earnings, to hedge existing positions, to increase market exposure and investment flexibility, and/or to increase credit exposure.

The Fund may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis. Such securities may include mortgage-backed securities acquired or sold in the “to be announced” (TBA) market and those in a dollar roll transaction.

In addition, under normal circumstances, the Fund uses forward foreign currency contracts in seeking to enhance returns based on fluctuations in the values of various foreign currencies relative to the U.S. dollar (the Currency Overlay Strategy). The Fund gains economic exposure to foreign currencies through its investment in forward foreign currency contracts comparable to the exposure that it would have had if it had bought or sold the foreign currencies directly.

The Fund may invest directly in derivatives or indirectly by investing in one or more offshore, wholly-owned subsidiaries (each, a Subsidiary, and, collectively, the Subsidiaries). Generally, Subsidiaries will invest in commodity futures, financial futures, option and swap contracts, fixed income securities, pooled investment vehicles, including those that are not registered pursuant to the Investment Company Act of 1940, as amended (the 1940 Act), and other investments intended to serve as margin or collateral for the Subsidiaries’ derivative positions.

The Fund expects to hold a significant amount of cash, money market instruments (which may include investments in one or more affiliated or unaffiliated money market funds or similar vehicles) or other high-quality, short-term investments to cover obligations with respect to, or that may result from, the Fund’s investments in forward foreign currency contracts, currency futures contracts, commodity-linked investments or other derivatives.

Principal Risks

An investment in the Fund involves risk, including those associated with the Fund’s investment in the Subsidiaries, as described below. There is no assurance that the Fund will achieve its investment objective and you may lose money . The value of the Fund’s holdings may decline, and the Fund’s net asset value (NAV) and share price may go down. (References in this section to “the Fund” also include the Subsidiaries, which share the same risks as the Fund.)

Active Management Risk. Due to its active management, the Fund could underperform its benchmark index and/or other funds with similar investment objectives.

Allocation  Risk. Because the Fund uses an asset allocation strategy in pursuit of its investment objective, there is a risk that the Fund's allocation among strategies and/or investment styles will cause the Fund's shares to lose value or cause the Fund to underperform other funds with a similar investment objective and/or strategies, or that the investments themselves will not produce the returns expected.

Prospectus 2015

5

Columbia Diversified Absolute Return Fund

Summary of the Fund (continued)

Commodity Futures Trading Commission (CFTC) Regulatory Risk. The Fund does not qualify for an exemption from registration as a “commodity pool” under rules of the Commodity Exchange Act (the CEA). Accordingly, the Fund is a commodity pool under the CEA and the Investment Manager is registered as a “commodity pool operator” under the CEA. The Fund is subject to dual regulation by the SEC and the CFTC. Compliance with the CFTC’s regulatory requirements could increase Fund expenses, adversely affecting the Fund’s total return.

Commodity-related Investment Risk. The value of commodities investments will generally be affected by overall market movements and factors specific to a particular industry or commodity, which may include demand for the commodity, weather, embargoes, tariffs, and economic health, political, international, regulatory and other developments. Exposure to commodities and commodities markets may subject the value of the Fund’s investments to greater volatility than other types of investments. Commodities investments may also subject the Fund to counterparty risk and liquidity risk. The Fund may make commodity-related investments through one or more wholly-owned subsidiaries organized outside the U.S. that are generally not subject to U.S. laws (including securities laws) and their protections.

Convertible Securities Risk. Convertible securities are subject to the usual risks associated with debt securities, such as interest rate risk and credit risk. Convertible securities also react to changes in the value of the common stock into which they convert, and are thus subject to market risk. The Fund may also be forced to convert a convertible security at an inopportune time, which may decrease the Fund’s return.

Counterparty Risk. Counterparty risk is the risk that a counterparty to a financial instrument held by the Fund or by a special purpose or structured vehicle invested in by the Fund may become insolvent or otherwise fail to perform its obligations. As a result, the Fund may obtain no or limited recovery of its investment, and any recovery may be significantly delayed.

Credit Risk. The value of fixed-income securities may decline if the issuer of the security defaults or otherwise becomes unable or unwilling, or is perceived to be unable or unwilling, to honor its financial obligations, such as making payments to the Fund when due. Rating agencies assign credit ratings to certain fixed-income securities to indicate their credit risk. Lower quality or unrated securities held by the Fund may present increased credit risk as compared to higher-rated securities. Non-investment grade loans or fixed-income securities (commonly called “high-yield” or “junk”) are subject to greater price fluctuations and are more likely to experience a default than investment grade loans or securities and therefore may expose the Fund to increased credit risk. If the Fund purchases unrated securities, or if the ratings of securities held by the Fund are lowered after purchase, the Fund will depend on analysis of credit risk more heavily than usual.

Derivatives Risk. Losses involving derivative instruments may be substantial, because a relatively small movement in the price of an underlying security, instrument, commodity, currency or index may result in a substantial loss for the Fund. In addition to the potential for increased losses, the use of derivative instruments may lead to increased volatility for the Fund. Derivative investments will typically increase the Fund’s exposure to principal risks to which it is otherwise exposed, and may expose the Fund to additional risks, including correlation risk, counterparty risk, hedging risk, leverage risk and/or liquidity risk.

Derivatives Risk/Commodity-Linked Futures Contracts Risk. The loss that may be incurred by the Fund in entering into futures contracts is potentially unlimited and may exceed the amount of the premium. Futures markets are highly volatile and the use of futures by the Fund may increase the volatility of the Fund’s NAV. Additionally, as a result of the low collateral deposits normally required in futures trading, a relatively small price movement in a futures contract may result in substantial losses to the Fund. Futures contracts may be illiquid. The liquidity of the futures market depends on participants entering into offsetting transactions rather than making or taking delivery. To the extent participants decide to make or take delivery, liquidity in the futures market could be reduced. Furthermore, exchanges may limit fluctuations in futures contract prices during a trading session by imposing a maximum permissible price movement on each futures contract. The Fund may be disadvantaged if it is prohibited from executing a trade outside the daily permissible price movement. Moreover, to the extent the Fund engages in futures contracts on foreign exchanges, such exchanges may not provide the same protection as U.S. exchanges.

Derivatives Risk/Commodity-Linked Swaps Risk.  Commodity-linked swaps could result in losses if the underlying asset (e.g., a particular commodity) or reference does not perform as anticipated. The value of swaps, like many other derivatives, may move in unexpected ways and may result in losses for the Fund. Such transactions can have the potential for unlimited losses. Such risk is heightened in the case of short swap transactions. Swaps can involve greater risks than direct investment in the underlying asset, because swaps may be leveraged (creating leverage risk) and are subject to counterparty risk, hedging risk, pricing risk and liquidity risk.

6	Prospectus 2015

Columbia Diversified Absolute Return Fund

Summary of the Fund (continued)

Derivatives Risk/Credit Default Swaps Risk. A credit default swap enables an investor to buy or sell protection against a credit event, such as an issuer’s failure to make timely payments of interest or principal, bankruptcy or restructuring. A credit default swap may be embedded within a structured note or other derivative instrument. Swaps can involve greater risks than direct investment in the underlying securities, because swaps may be leveraged (creating leverage risk, the risk that losses from the derivative instrument may be greater than the amount invested in the derivative instrument) and subject the Fund to counterparty risk, hedging risk, pricing risk and liquidity risk. If the Fund is selling credit protection, there is a risk that a credit event will occur and that the Fund will have to pay the counterparty. If the Fund is buying credit protection, there is a risk that no credit event will occur and the Fund will receive no benefit for the premium paid.

Derivatives Risk/Forward Foreign Currency Contracts Risk. These instruments are a type of derivative contract whereby 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. Investment in these instruments also subjects the Fund to counterparty risk. The Fund’s strategy of investing in these instruments may not be successful and the Fund may experience significant losses as a result.

Derivatives Risk/Forward Interest Rate Agreements Risk. Under forward interest rate agreements, the buyer locks in an interest rate at a future settlement date. If the interest rate on the settlement date exceeds the lock rate, the buyer pays the seller the difference between the two rates (based on the notional value of the agreement). If the lock rate exceeds the interest rate on the settlement date, the seller pays the buyer the difference between the two rates (based on the notional value of the agreement). The Fund may act as a buyer or a seller. These transactions involve risks, including counterparty risk, hedging risk and interest rate risk.

Derivatives Risk/Futures Contracts Risk. The loss that may be incurred in entering into futures contracts may exceed the amount of the premium paid and may be potentially unlimited. Futures markets are highly volatile and the use of futures may increase the volatility of the Fund’s NAV. Additionally, as a result of the low collateral deposits normally involved in futures trading, a relatively small price movement in a futures contract may result in substantial losses for the Fund. Futures contracts may be illiquid. Furthermore, exchanges may limit fluctuations in futures contract prices during a trading session by imposing a maximum permissible price movement on each futures contract. The Fund may be disadvantaged if it is prohibited from executing a trade outside the daily permissible price movement. Futures contracts executed on foreign exchanges may not provide the same protection as U.S. exchanges. These transactions involve additional risks, including counterparty risk, hedging risk and pricing risk.

Derivatives Risk/Interest Rate Swaps Risk. Interest rate swaps can be based on various measures of interest rates, including the London Interbank Offered Rate (commonly known as LIBOR), swap rates, treasury rates and other foreign interest rates. A swap agreement can increase or decrease the volatility of the Fund's investments and its NAV. The value of swaps, like many other derivatives, may move in unexpected ways and may result in losses for the Fund. Swaps can involve greater risks than direct investment in securities, because swaps may be leveraged, and are, among other factors, subject to counterparty risk (the risk that the counterparty to the instrument will not perform or be able to perform in accordance with the terms of the instrument), hedging and correlation risk (the risk that a hedging strategy may not eliminate the risk that it is intended to offset, and may offset gains, including because of a lack of correlation between the swaps and the portfolio of bonds that the swaps are designed to hedge or replace), pricing risk (swaps may be difficult to value), liquidity risk (it may not be possible to liquidate a swap position at an advantageous time or price) and interest rate risk (the risk of losses attributable to changes in interest rates), each of which may result in significant losses for the Fund.

Derivatives Risk/Options Risk. The use of options is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. If the Fund sells a put option, there is a risk that the Fund may be required to buy the underlying asset at a disadvantageous price. If the Fund sells a call option, there is a risk that the Fund may be required to sell the underlying asset at a disadvantageous price, and if the call option sold is not covered (for example, by owning the underlying asset), the Fund's losses are potentially unlimited. These transactions involve other risks, including counterparty risk and hedging risk.

Derivatives Risk/Swaps Risk. The use of swaps is a highly specialized activity that involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. Swaps could result in Fund losses if the underlying asset or reference does not perform as anticipated. The value of swaps, like many other derivatives, may move in

Prospectus 2015

7

Columbia Diversified Absolute Return Fund

Summary of the Fund (continued)

unexpected ways and may result in losses for the Fund. Such transactions can have the potential for unlimited losses. Such risk is heightened in the case of short swap transactions involving short exposures. Swaps can involve greater risks than direct investment in the underlying asset, because swaps may be leveraged (creating leverage risk) and are subject to counterparty risk, hedging risk, pricing risk and liquidity risk.

Derivatives Risk/Portfolio Swaps and Total Return Swaps Risk. The use of portfolio swaps or total return swaps is a highly specialized activity that involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. Portfolio swaps and equity swaps could result in losses if the underlying asset or reference does not perform as anticipated. The value of swaps, like many other derivatives, may move in unexpected ways and may result in losses for the Fund. Such transactions can have the potential for unlimited losses. Such risk is heightened in the case of short swap transactions. Swaps can involve greater risks than direct investment in the underlying asset, because swaps may be leveraged (creating leverage risk) and are subject to counterparty risk, hedging risk, pricing risk and liquidity 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 and economic 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.

Exchange-Traded Fund (ETF) Risk. ETFs are subject to, among other risks, tracking risk and passive and, in some cases, active investment risk. In addition, shareholders bear both their proportionate share of the Fund’s expenses and similar expenses incurred through ownership of the ETF.

Foreign Currency Risk. The performance of the Fund may be materially affected positively or negatively by foreign currency strength or weakness relative to the U.S. dollar, particularly if the Fund invests a significant percentage of its assets in foreign securities or other assets denominated in currencies other than the U.S. dollar.

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 the political, regulatory, economic, social, diplomatic and other conditions or events 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. The performance of the Fund may be negatively impacted by fluctuations in a foreign currency’s strength or weakness relative to the U.S. dollar, particularly if the Fund invests a significant percentage of its assets in foreign securities or other assets denominated in currencies other than the U.S. dollar.

Forward Commitments on Mortgage-backed Securities (including Dollar Rolls) Risk. When purchasing mortgage-backed securities in the “to be announced” (TBA) market (MBS TBAs), the seller agrees to deliver mortgage-backed securities for an agreed upon price on an agreed upon date, but may make no guarantee as to the specific securities to be delivered. In lieu of taking delivery of mortgage-backed securities, the Fund could enter into dollar rolls, which are transactions in which the Fund sells securities to a counterparty and simultaneously agrees to purchase those or similar securities in the future at a predetermined price. Dollar rolls involve the risk that the market value of the securities the Fund is obligated to repurchase may decline below the repurchase price, or that the counterparty may default on its obligations. These transactions may also increase the Fund’s portfolio turnover rate. If the Fund reinvests the proceeds of the security sold, the Fund will also be subject to the risk that the investments purchased with such proceeds will decline in value (a form of leverage risk). MBS TBAs and dollar rolls are subject to counterparty risk.

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Columbia Diversified Absolute Return Fund

Summary of the Fund (continued)

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.

Hedging Transactions Risk. The Fund may invest in securities and utilize financial instruments for a variety of hedging purposes. Hedging transactions may limit the opportunity for gain if the value of the portfolio position should increase. There can be no assurance that the Fund will engage in hedging transactions at any given time, even under volatile market conditions, or that any hedging transactions the Fund engages in will be successful. Moreover, it may not be possible for the Fund to enter into a hedging transaction at a price sufficient to protect its assets. The Fund may not anticipate a particular risk so as to hedge against it.

High-Yield Securities Risk. Securities rated below investment grade (commonly called “high-yield” or “junk” bonds) and unrated securities of comparable quality expose the Fund to a greater risk of loss of principal and income than a fund that invests solely or primarily in investment grade securities. In addition, these investments have greater price fluctuations, are less liquid and are more likely to experience a default than higher-rated securities. High-yield securities are considered to be predominantly speculative with respect to the issuer’s capacity to pay interest and repay principal.

Interest Rate Risk. Interest rate risk is the risk of losses attributable to changes in interest rates. In general, if prevailing interest rates rise, the values of debt securities tend to fall, and if interest rates fall, the values of debt securities tend to rise. Changes in the value of a debt security usually will not affect the amount of income the Fund receives from it but will usually affect the value of the Fund's shares. In general, the longer the maturity or duration of a debt security, the greater its sensitivity to changes in interest rates. Interest rate declines also may increase prepayments of debt obligations, which, in turn, would increase prepayment risk. Similarly, a period of rising interest rates may negatively impact the Fund’s performance. Actions by governments and central banking authorities can result in increases in interest rates. Such actions may negatively affect the value of fixed-income securities held by the Fund, resulting in a negative impact on the Fund's performance and NAV.

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 a 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 fund. 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 another underlying fund(s), 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(s) does not present itself timely or at all.

Investing in Wholly-Owned Subsidiary Risk. By investing in a Subsidiary, the Fund is indirectly exposed to the risks associated with the Subsidiary’s investments. The Fund’s Principal Risks may also apply to a Subsidiary in which the Fund invests (which are described in this prospectus). There can be no assurance that the investment objective of a Subsidiary will be achieved. Changes in the laws of the United States and/or the Cayman Islands, under which the Fund and any Subsidiary in which it invests, respectively, are organized, could result in the inability of the Fund and/or the Subsidiary to operate as described in this prospectus and the Fund’s SAI and could adversely affect the Fund and its shareholders.

Prospectus 2015

9

Columbia Diversified Absolute Return Fund

Summary of the Fund (continued)

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.

Leverage Risk. Leverage occurs when the Fund increases its assets available for investment using borrowings, short sales, derivatives, or similar instruments or techniques. Because short sales involve borrowing securities and then selling them, the Fund’s short sales effectively leverage the Fund’s assets. The Fund's assets that are used as collateral to secure the Fund's obligations to return the securities sold short may decrease in value while the short positions are outstanding, which may force the Fund to use its other assets to increase the collateral. Leverage can create an interest expense that may lower the Fund's overall returns. Leverage presents the opportunity for increased net income and capital gains, but may also exaggerate the Fund’s volatility and risk of loss. There can be no guarantee that a leveraging strategy will be successful.

Liquidity Risk. Liquidity risk is the risk associated with a lack of marketability of investments which may make it difficult to sell the investment at a desirable time or price. Decreases in the number of financial institutions willing to make markets in the Fund’s investments or in their capacity or willingness to transact may increase the Fund’s exposure to this risk. Changing regulatory, market or other conditions or environments (for example, the interest rate or credit environments) may also adversely affect the liquidity of the Fund's investments. The Fund may have to accept a lower selling price for the holding, sell other investments, or forego another, more appealing investment opportunity. Judgment plays a larger role in valuing these investments as compared to valuing more liquid investments. Price volatility may be higher for illiquid investments as a result of, for example, the relatively less frequent pricing of such securities (as compared to 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. Price volatility, liquidity of the market and other factors can lead to an increase in Fund redemptions, which may negatively impact Fund performance and NAV, including, for example, if the Fund is forced to sell securities in a down market.

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. Although equity securities generally tend to have greater price volatility than debt securities, under certain market conditions, debt securities may have comparable or greater price volatility.

Money Market Fund Investment Risk. An investment in a money market fund is not a bank deposit and is not insured or guaranteed by any bank, the FDIC or any other government agency. Although money market funds seek to preserve the value of investments at $1.00 per share, it is possible for the Fund to lose money by investing in money market funds. In addition to the fees and expenses that the Fund directly bears, the Fund indirectly bears the fees and expenses of any money market funds in which it invests, including affiliated money market funds. The Fund will also be exposed to the investment risks of the money market fund. To the extent the Fund invests in instruments such as derivatives, the Fund may hold investments, which may be significant, in money market fund shares to cover its obligations resulting from its investments in derivatives.

Mortgage- and Other Asset-Backed Securities Risk.  The value of any mortgage-backed and other asset-backed securities held by the Fund may be affected by, among other things, changes or perceived changes in: interest rates; factors concerning the interests in and structure of the issuer or the originator of the mortgages or other assets; the creditworthiness of the entities that provide any supporting letters of credit, surety bonds or other credit enhancements; or the market's assessment of the quality of underlying assets. Payment of principal and interest on some mortgage-backed securities (but not the market value of the securities themselves) may be guaranteed by the full faith and credit of a particular U.S. Government agency, authority, enterprise or instrumentality, and some, but not all, are also insured or guaranteed by the U.S. Government. Mortgage-backed securities issued by non-governmental issuers (such as commercial banks, savings and loan institutions, private mortgage insurance companies, mortgage bankers and other secondary market issuers) may entail greater risk than obligations guaranteed by the U.S. Government. Mortgage- and other asset-backed securities are subject to prepayment risk, which is the possibility that the underlying mortgage or other asset may be refinanced or prepaid prior to maturity during periods of declining or low interest rates, causing the Fund to have to reinvest the money received in securities that have lower yields. Rising or high interest rates tend to extend the duration of mortgage- and other asset-backed securities, making their prices more volatile and more sensitive to changes in interest rates.

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Summary of the Fund (continued)

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).

Prepayment and Extension Risk. Prepayment and extension risk is the risk that a loan, bond or other security or investment might, in the case of prepayment risk, be called or otherwise converted, prepaid or redeemed before maturity and, in the case of extension risk, the investment might not be called as expected, and the portfolio managers may not be able to invest the proceeds in other investments providing as high a level of income, resulting in a reduced yield to the Fund. In the case of mortgage- or asset-backed securities, as interest rates decrease or spreads narrow, the likelihood of prepayment increases. Conversely, extension risk is the risk that an unexpected rise in interest rates will extend the life of a mortgage- or asset-backed security beyond the prepayment time. If the Fund’s investments are locked in at a lower interest rate for a longer period of time, the portfolio managers may be unable to capitalize on securities with higher interest rates or wider spreads.

Quantitative Model Risk. Investments selected using quantitative methods may perform differently from the market as a whole. There can be no assurance that these methodologies will enable the Fund to achieve its objective.

Short Positions Risk. The Fund may establish short positions which introduce more risk to the Fund than long positions (where the Fund owns the instrument or other asset) because the maximum sustainable loss on an instrument or other asset purchased (held long) is limited to the amount paid for the instrument or other asset plus the transaction costs, whereas there is no maximum price of the shorted instrument or other asset when purchased in the open market. Therefore, in theory, short positions have unlimited risk. The Fund’s use of short positions in effect “leverages” the Fund. Leverage potentially exposes the Fund to greater risks of loss due to unanticipated market movements, which may magnify losses and increase the volatility of returns. To the extent the Fund takes a short position in a derivative instrument or other asset, this involves the risk of a potentially unlimited increase in the value of the underlying instrument or other asset.

Sovereign Debt Risk. A sovereign debtor’s willingness or ability to repay principal and pay interest in a timely manner may be affected by a variety of factors, including its cash flow situation, the extent of its reserves, the availability of sufficient foreign exchange on the date a payment is due, the relative size of the debt service burden to the economy as a whole, the sovereign debtor’s policy toward international lenders, and the political constraints to which a sovereign debtor may be subject. Sovereign debt risk is increased for emerging market issuers.

Tax Risk. The Fund intends to qualify for treatment as a regulated investment company under the Internal Revenue Code of 1986, as amended (the Code). In order to so qualify, the Fund must meet certain requirements regarding the source of its income. Certain instruments in which the Fund is permitted to invest do not give rise to qualifying income. If the Fund were to fail to limit its income from such investments appropriately, absent a cure the Fund would be unable to qualify for treatment as a regulated investment company. The tax treatment of certain investments and of the income and gain therefrom under the qualifying income test applicable to regulated investment companies is uncertain. An adverse determination or future guidance by the Internal Revenue Service (the IRS) regarding such investments or the income and gain from such investments might affect the Fund’s ability to qualify for treatment as a regulated investment company, including on a retroactive basis.

If the Fund were to fail to qualify as a regulated investment company, or if it were ineligible to or otherwise could not cure such failure, the Fund would be ineligible for the favorable tax treatment afforded to regulated investment companies for one or more years, which would adversely affect the value of the Fund. Please refer to “Distributions and Taxes” in this prospectus or to “Taxation” in the SAI for additional information about the U.S. federal income tax treatment of the Fund.

U.S. Government Obligations Risk. While U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. Government, such securities are nonetheless subject to credit risk (i.e., the risk that the U.S. Government may be, or be perceived to be, unable or unwilling to honor its financial obligations, such as making payments). Securities issued or guaranteed by federal agencies or authorities and U.S. Government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. Government.

Valuation Risk. The sales price the Fund (or an underlying fund or other investment vehicle) could receive for any particular investment may differ from the Fund’s (or an underlying fund’s or other investment vehicle’s) valuation of the investment, particularly for securities that trade in thin or volatile markets or that are valued using a fair value methodology that produces an

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Summary of the Fund (continued)

estimate of the fair value of the security/instrument, which may prove to be inaccurate. Investors who purchase or redeem Fund shares on days when the Fund is holding securities or other instruments (or holding shares of underlying funds or other investment vehicles that have fair-valued securities or other instruments in their portfolios) may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the Fund (or underlying fund or other investment vehicle) had not fair-valued the security or instrument or had used a different valuation methodology.

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 Citigroup 1-Month U.S. Treasury Bill Index.

When available, updated performance information can be obtained by calling toll-free 800.345.6611 or visiting columbiamanagement.com.

Fund Management

Investment Manager: Columbia Management Investment Advisers, LLC

    

In managing the Fund, the portfolio managers allocate portions of Fund assets to be managed by investment professionals in other investment manager’s teams.

Purchase and Sale of Fund Shares

You may purchase or redeem shares of the Fund on any business day by contacting the Fund in the ways described below:

    

You may purchase shares and receive redemption proceeds by electronic funds transfer, by check or by wire. If you maintain your account with a broker-dealer or other financial intermediary, you must contact that financial intermediary to buy, sell or exchange shares of the Fund through your account with the intermediary.

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Columbia Diversified Absolute Return Fund

More Information About the Fund (continued)

The Fund may invest in fixed income securities of any maturity and does not seek to maintain a particular dollar-weighted average maturity. A bond is issued with a specific maturity date, which is the date when the issuer must pay back the bond’s principal (face value). Bond maturities range from less than 1 year to more than 30 years. Typically, the longer a bond’s maturity, the more price risk the Fund and the Fund’s investors face as interest rates rise, but the Fund could receive a higher yield in return for that longer maturity and higher interest rate risk.

The Fund may invest in derivatives such as futures (including bond, currency, equity index, interest rate and volatility index futures), forward foreign currency contracts, forward interest rate agreements, options and swap contracts (including credit default swaps, interest rate swaps and total return swaps), in an effort to produce incremental earnings, to hedge existing positions, to increase market exposure and investment flexibility, and/or to increase credit exposure. Futures, forwards and swaps, in particular, are expected to be utilized to gain long and short investment (or credit) exposures to securities, indexes, interest rates or currencies (in lieu of purchasing or selling a security, currency or other instrument directly).

The Fund may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis. Such securities may include mortgage-backed securities in the “to be announced” (TBA) market and may be acquired or sold in a dollar roll transaction.

In addition, under normal circumstances, the Fund uses forward foreign currency contracts in seeking to enhance returns based on fluctuations in the values of various foreign currencies relative to the U.S. dollar (the Currency Overlay Strategy). The Fund gains economic exposure to foreign currencies through its investment in forward foreign currency contracts comparable to the exposure that it would have had if it had bought or sold the foreign currencies directly.

The Currency Overlay Strategy uses a quantitative, proprietary model that applies various fundamental and technical factors, including based on current and historical data, to rank the anticipated value of several developed countries’ currencies relative to the U.S. dollar, subject to other considerations (including other fundamental, technical, and macroeconomic factors) in the Investment Manager’s discretion that may affect these rankings. The Fund typically enters into long forward foreign currency contracts for currencies that rank higher in the model, and it will experience profits (losses) to the extent the value of the currency appreciates (depreciates) relative to the U.S. dollar; and conversely, the Fund typically enters into short forward foreign currency contracts for currencies that rank lower in the model, and it will experience profits (losses) to the extent the value of the currency depreciates (appreciates) relative to the U.S. dollar.

The Fund may invest directly in derivatives or indirectly by investing in one or more offshore, wholly-owned subsidiaries (each, a Subsidiary, and, collectively, the Subsidiaries) that are subject to the same fundamental investment restrictions, compliance policies and procedures as the Fund, but which are not expected to offer or sell their shares to investors other than the Fund.

Generally, Subsidiaries will invest in commodity futures, financial futures, option and swap contracts, fixed income securities, pooled investment vehicles, including those that are not registered pursuant to the Investment Company Act of 1940, as amended (the 1940 Act), and other investments intended to serve as margin or collateral for the Subsidiaries’ derivative positions.

Unlike the Fund (which is subject to limitations under federal tax laws), Subsidiaries may invest without limitation in commodity-linked derivatives; however, the Fund, in combination with its Subsidiaries, will comply with the same 1940 Act asset coverage requirements with respect to the Subsidiaries’ investments in commodity-linked derivatives that are applicable to the Fund’s direct transactions in derivatives.

The Fund expects to hold a significant amount of cash, money market instruments (which may include investments in one or more affiliated or unaffiliated money market funds or similar vehicles) or other high-quality, short-term investments to cover obligations with respect to, or that may result from, the Fund’s investments in forward foreign currency contracts, currency futures contracts, commodity-linked investments or other derivatives.

In managing the Fund, the portfolio managers allocate portions of Fund assets to be managed by investment professionals in other investment manager’s teams.

Investment Process

Columbia Management Investment Advisers, LLC (the Investment Manager) employs a variety of investment strategies, techniques and practices that, in the aggregate, are designed to seek positive long-term returns, while seeking to capitalize on market inefficiencies. The Investment Manager seeks to identify investments that have the potential to exploit inefficiencies or mispricings within individual markets or across markets.

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The Investment Manager identifies asset classes and related investment strategies for allocation of the Fund’s assets based on a number of qualitative and quantitative factors, including an assessment of their expected: relative return, risk, volatility and correlation with the performance of other asset classes, strategies and major market indexes. On at least a monthly basis, the Fund’s investment allocations are reviewed and, as a result, may be rebalanced by the Investment Manager based on the foregoing factors. The Investment Manager also considers prevailing market, economic, and other conditions and has the flexibility to adjust allocations, at any time, to align the portfolio with expected conditions.

Principal Risks

An investment in the Fund involves risk, including those associated with the Fund’s investment in the Subsidiaries, as described below. There is no assurance that the Fund will achieve its investment objective and you may lose money . The value of the Fund’s holdings may decline, and the Fund’s net asset value (NAV) and share price may go down. (References in this section to “the Fund” also include the Subsidiaries, which share the same risks as the Fund.)

Active Management Risk. The Fund is actively managed and its performance therefore will reflect, in part, the ability of the portfolio managers to make investment decisions that will achieve the Fund’s investment objective. Due to its active management, the Fund could underperform its benchmark index and/or other funds with similar investment objectives and/or strategies.

Allocation  Risk. Because the Fund uses an asset allocation strategy in pursuit of its investment objective, there is a risk that the Fund's allocation among strategies and/or investment styles will cause the Fund's shares to lose value or cause the Fund to underperform other funds with a similar investment objective and/or strategies, or that the investments themselves will not produce the returns expected.

Commodity Futures Trading Commission (CFTC) Regulatory Risk. The Fund does not qualify for an exemption from registration as a “commodity pool” under rules of the Commodity Exchange Act (the CEA). Accordingly, the Fund is a commodity pool under the CEA and the Investment Manager is registered as a “commodity pool operator” under the CEA. The Fund is subject to dual regulation by the SEC and the CFTC. Compliance with the CFTC’s regulatory requirements could increase Fund expenses, adversely affecting the Fund’s total return.

Commodity-related Investment Risk. The value of commodities investments will generally be affected by overall market movements and factors specific to a particular industry or commodity, which may include demand for the commodity, weather, embargoes, tariffs, and economic health, political, international, regulatory and other developments. Economic and other events (whether real or perceived) can reduce the demand for commodities, which may, in turn, reduce market prices and cause the value of Fund shares to fall. The frequency and magnitude of such changes cannot be predicted. Exposure to commodities and commodities markets may subject the value of the underlying fund’s investments to greater volatility than other types of investments. No, or limited, active trading market may exist for certain commodities investments, which may impair the ability to sell or to realize the full value of such investments in the event of the need to liquidate such investments. In addition, adverse market conditions may impair the liquidity of actively traded commodities investments. Certain types of commodities instruments are subject to the risk that the counterparty to the instrument may not perform or be unable to perform in accordance with the terms of the instrument. The Fund may make commodity-related investments through one or more wholly-owned subsidiaries organized outside the U.S. that are generally not subject to U.S. laws (including securities laws) and their protections. However, any such subsidiary is wholly owned and controlled by the Fund , making it unlikely that the subsidiary will take action contrary to the interests of the Fund and its shareholders. Further, any such subsidiaries will be subject to the laws of a foreign jurisdiction, and can be adversely affected by developments in that jurisdiction.

Convertible Securities Risk. Convertible securities are subject to the usual risks associated with debt securities, such as interest rate risk (the risk of losses attributable to changes in interest rates) and credit risk (the risk that the issuer of a debt security will default or otherwise become unable, or be perceived to be unable or unwilling, to honor a financial obligation, such as making payments to the Fund when due). Convertible securities also react to changes in the value of the common stock into which they convert, and are thus subject to market risk (the risk that the market values of securities or other investments that the Fund holds will fall, sometimes rapidly or unpredictably, or fail to rise). Because the value of a convertible security can be influenced by both interest rates and the common stock's market movements, a convertible security generally is not as sensitive to interest rates as a similar debt security, and generally will not vary in value in response to other factors to the same extent as the underlying

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common stock. In the event of a liquidation of the issuing company, holders of convertible securities would typically be paid before the company's common stockholders but after holders of any senior debt obligations of the company. The Fund may be forced to convert a convertible security before it otherwise would choose to do so, which may decrease the Fund's return.

Counterparty Risk. The risk exists that a counterparty to a financial instrument held by the Fund or by a special purpose or structured vehicle in which the Fund invests may become insolvent or otherwise fail to perform its obligations due to financial difficulties, including making payments to the Fund. The Fund may obtain no or limited recovery in a bankruptcy or other organizational proceedings, and any recovery may be significantly delayed. Transactions that the Fund enters into may involve counterparties in the financial services sector and, as a result, events affecting the financial services sector may cause the Fund’s share value to fluctuate.

Credit Risk. The value of fixed-income securities may decline if the issuer of the security defaults or otherwise becomes unable or unwilling, or is perceived to be unable or unwilling, to honor its financial obligations, such as making payments to the Fund when due. Various factors could affect the actual or perceived willingness or ability of the issuer to make timely interest or principal payments, including changes in the financial condition of the issuer or in general economic conditions. Fixed-income securities backed by an issuer's taxing authority may be subject to legal limits on the issuer's power to increase taxes or otherwise to raise revenue, or may be dependent on legislative appropriation or government aid. Certain fixed-income securities are backed only by revenues derived from a particular project or source, rather than by an issuer's taxing authority, and thus may have a greater risk of default. Rating agencies assign credit ratings to certain fixed-income securities to indicate their credit risk. Lower quality or unrated securities held by the Fund may present increased credit risk as compared to higher-rated securities. Non-investment grade fixed-income securities (commonly called “high-yield” or “junk”) are subject to greater price fluctuations and are more likely to experience a default than investment grade securities and therefore may expose the Fund to increased credit risk. If the Fund purchases unrated fixed-income securities, or if the ratings of securities held by the Fund are lowered after purchase, the Fund will depend on analysis of credit risk more heavily than usual.

Derivatives Risk. Derivatives are financial instruments whose value depends on, or is derived from, the value of other underlying assets. Losses involving derivative instruments may be substantial, because a relatively small movement in the price of an underlying security, instrument, commodity, currency or index may result in a substantial loss for the Fund. In addition to the potential for increased losses, the use of derivative instruments may lead to increased volatility for the Fund. Derivative investments will typically increase the Fund’s exposure to principal risks to which it is otherwise exposed, and may expose the Fund to additional risks. Depending on the type and purpose of the Fund’s derivative investments, these risks may include: correlation risk (there may be an imperfect correlation between the hedge and the opposite position, which is related to hedging risk), counterparty risk (the counterparty to the instrument may not perform or be able to perform in accordance with the terms of the instrument), leverage risk (losses from the derivative instrument may be greater than the amount invested in the derivative instrument), hedging risk (the risk that a hedging strategy may not eliminate the risk that it is intended to offset, and may offset gains), and/or liquidity risk (it may not be possible for the Fund to liquidate the instrument at an advantageous time or price), each of which may result in significant losses for the Fund.

Derivatives Risk/Commodity-Linked Futures Contracts Risk. The loss that may be incurred by the Fund in entering into futures contracts is potentially unlimited and may exceed the amount of the premium. Futures markets are highly volatile and the use of futures by the Fund may increase the volatility of the Fund’s NAV. Additionally, as a result of the low collateral deposits normally required in futures trading, a relatively small price movement in a futures contract may result in substantial losses to the Fund. Futures contracts may be illiquid. The liquidity of the futures market depends on participants entering into offsetting transactions rather than making or taking delivery. To the extent participants decide to make or take delivery, liquidity in the futures market could be reduced. Furthermore, exchanges may limit fluctuations in futures contract prices during a trading session by imposing a maximum permissible price movement on each futures contract. The Fund may be disadvantaged if it is prohibited from executing a trade outside the daily permissible price movement. Moreover, to the extent the Fund engages in futures contracts on foreign exchanges, such exchanges may not provide the same protection as U.S. exchanges.

Derivatives Risk/Commodity-Linked Swaps Risk. The use of commodity-linked swaps is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. Commodity-linked swaps could result in losses if the underlying asset or reference does not perform as anticipated. The value of swaps, like many other derivatives, may move in unexpected ways and may result in losses for the Fund. Such transactions can have the potential for unlimited losses. Such risk is heightened in the case of short swap transactions. Swaps can involve greater risks than direct investment in the underlying asset, because swaps may be leveraged (creating leverage risk) and are subject to

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counterparty risk (the risk that the counterparty to the instrument will not perform or be able to perform in accordance with the terms of the instrument), hedging risk (the risk that a hedging strategy may not eliminate the risk that it is intended to offset, and may offset gains), pricing risk (swaps may be difficult to value) and liquidity risk (the risk that it may not be possible to liquidate a swap position at an advantageous time or price), each of which may result in significant losses for the Fund.

Derivatives Risk/Credit Default Swaps Risk. The use of credit default swaps is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. A credit default swap enables an investor to buy or sell protection against a credit event, such as an issuer’s failure to make timely payments of interest or principal, bankruptcy or restructuring. A credit default swap may be embedded within a structured note or other derivative instrument. The value of swaps, like many other derivatives, may move in unexpected ways and may result in losses for the Fund. Swaps can involve greater risks than direct investment in the underlying securities, because swaps, among other factors, may be leveraged (creating leverage risk, the risk that losses from the derivative instrument may be greater than the amount invested in the derivative instrument) and subject the Fund to counterparty risk (the risk that the counterparty to the instrument will not perform or be unable to perform in accordance with the terms of the instrument), hedging risk (the risk that a hedging strategy may not eliminate the risk that it is intended to offset, and may offset gains), pricing risk (the risk that swaps may be difficult to value) and liquidity risk (it may not be possible for the Fund to liquidate a swap position at an advantageous time or price), each of which may result in significant losses for the Fund. If the Fund is selling credit protection, there is a risk that a credit event will occur and that the Fund will have to pay the counterparty. If the Fund is buying credit protection, there is a risk that no credit event will occur.

Derivatives Risk/Forward Foreign Currency Contracts Risk. The use of these derivatives is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. These instruments are a type of derivative contract, whereby 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 in currencies other than the U.S. dollar). The effectiveness of any currency strategy by a Fund may be reduced by the Fund's inability to precisely match forward contract amounts and the value of securities involved. Forward foreign currency contracts used for hedging may also limit any potential gain that might result from an increase or decrease in the value of the currency. Unanticipated changes in the currency markets could result in reduced performance for the Fund or losses. 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 movement in forward contract prices. 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. Investment in these instruments also subjects the Fund, among other factors, to counterparty risk (the risk that the counterparty to the instrument will not perform or will be unable to perform in accordance with the terms of the instrument). The Fund’s strategy of investing in these instruments may not be successful and the Fund may experience significant losses as a result.

Derivatives Risk/Forward Interest Rate Agreements Risk. Under forward interest rate agreements, the buyer locks in an interest rate at a future settlement date. If the interest rate on the settlement date exceeds the lock rate, the buyer pays the seller the difference between the two rates (based on the notional value of the agreement). If the lock rate exceeds the interest rate on the settlement date, the seller pays the buyer the difference between the two rates (based on the notional value of the agreement). The Fund may act as a buyer or a seller. Investment in these instruments subjects the Fund to risks, including counterparty risk (the risk that the counterparty to the instrument will not perform or be able to perform in accordance with the terms of the instrument), hedging risk (the risk that a hedging strategy may not eliminate the risk that it is intended to offset, and may offset gains) and interest rate risk (the risk of losses attributable to changes in interest rates), each of which may result in significant losses for the Fund.

Derivatives Risk/Futures Contracts Risk. The use of futures contracts is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. A futures contract is a sales contract between a buyer (holding the “long” position) and a seller (holding the “short” position) for an asset with delivery deferred until a future date. The buyer agrees to pay a fixed price at the agreed future date and the seller agrees to deliver the asset. 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. The liquidity of the futures markets depends on participants entering into offsetting transactions rather

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than making or taking delivery. To the extent participants decide to make or take delivery, liquidity in the futures market could be reduced. In addition, futures exchanges often impose a maximum permissible price movement on each futures contract for each trading session. The Fund may be disadvantaged if it is prohibited from executing a trade outside the daily permissible price movement. Moreover, to the extent the Fund engages in futures contracts on foreign exchanges, such exchanges may not provide the same protection as U.S. exchanges. The loss that the Fund may incur in entering into futures contracts may exceed the amount of the premium paid and may be potentially unlimited. Futures markets are highly volatile and the use of futures may increase the volatility of the Fund’s NAV. Additionally, as a result of the low collateral deposits normally involved in futures trading, a relatively small price movement in a futures contract may result in substantial losses for the Fund. Investments in these instruments involve risks, including counterparty risk (the risk that the counterparty to the instrument may not perform or be able to perform in accordance with the terms of the instrument), hedging risk (the risk that a hedging strategy may not eliminate the risk that it is intended to offset, and may offset gains) and pricing risk (the risk that the instrument may be difficult to value), each of which may result in significant losses for the Fund.

Derivatives Risk/Interest Rate Swaps Risk. Interest rate swaps can be based on various measures of interest rates, including the London Interbank Offered Rate (commonly known as LIBOR), swap rates, treasury rates and other foreign interest rates. A swap agreement can increase or decrease the volatility of the Fund's investments and its NAV. The value of swaps, like many other derivatives, may move in unexpected ways and may result in losses for the Fund. Swaps can involve greater risks than direct investment in securities, because swaps may be leveraged, and are, among other factors, subject to counterparty risk (the risk that the counterparty to the instrument will not perform or be able to perform in accordance with the terms of the instrument), hedging and correlation risk (the risk that a hedging strategy may not eliminate the risk that it is intended to offset, and may offset gains, including because of a lack of correlation between the swaps and the portfolio of bonds that the swaps are designed to hedge or replace), pricing risk (swaps may be difficult to value), liquidity risk (it may not be possible to liquidate a swap position at an advantageous time or price) and interest rate risk (the risk of losses attributable to changes in interest rates), each of which may result in significant losses for the Fund.

Derivatives Risk/Options Risk. The use of options is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. If the Fund sells a put option, there is a risk that the Fund may be required to buy the underlying asset at a disadvantageous price. If the Fund sells a call option, there is a risk that the Fund may be required to sell the underlying asset at a disadvantageous price, and if the call option sold is not covered (for example, by owning the underlying asset), the Fund's losses are potentially unlimited. Options may be traded on a securities exchange or in the over-the-counter market. These transactions involve other risks, including counterparty risk (the risk that the counterparty to the instrument will not perform or be able to perform in accordance with the terms of the instrument) and hedging risk (the risk that a hedging strategy may not eliminate the risk that it is intended to offset, and may offset gains), each of which may result in significant losses for the Fund.

Derivatives Risk/Swaps Risk. The use of swaps is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. In a swap transaction, one party agrees to pay the other party an amount equal to the return, based upon an agreed-upon notional value, of a defined underlying asset or a non-asset reference (such as an index) during a specified period of time. In return, the other party would make periodic payments based on a fixed or variable interest rate or on the return from a different underlying asset or non-asset reference based upon an agreed-upon notional value. Swaps could result in Fund losses if the underlying asset or reference does not perform as anticipated. The value of swaps, like many other derivatives, may move in unexpected ways and may result in losses for the Fund. Such transactions can have the potential for unlimited losses. Such risk is heightened in the case of swap transactions involving short exposures. Swaps can involve greater risks than direct investment in the underlying asset, because swaps may be leveraged (creating leverage risk in that the Fund’s exposure and potential losses are greater than the amount invested) and are subject to counterparty risk (the risk that the counterparty to the instrument will not perform or be able to perform in accordance with the terms of the instrument), hedging risk (the risk that a hedging strategy may not eliminate the risk that it is intended to offset, and may offset gains), pricing risk (swaps may be difficult to value) and liquidity risk (it may not be possible to liquidate a swap position at an advantageous time or price), each of which may result in significant losses for the Fund.

Derivatives Risk/Portfolio Swaps and Total Return Swaps Risk. The use of portfolio swaps or total return swaps is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. In a swap transaction, one party agrees to pay the other party an amount equal to the total return of a defined underlying asset (such as an equity security or basket of such securities) or a non-asset reference (such as an index)

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during a specified period of time. In return, the other party would make periodic payments based on a fixed or variable interest rate or on the total return from a different underlying asset or non-asset reference. Portfolio swaps and equity swaps could result in losses if the underlying asset or reference does not perform as anticipated. The value of swaps, like many other derivatives, may move in unexpected ways and may result in losses for the Fund. Such transactions can have the potential for unlimited losses. Such risk is heightened in the case of short swap transactions. Swaps can involve greater risks than direct investment in the underlying asset, because swaps may be leveraged (creating leverage risk) and are subject to counterparty risk (the risk that the counterparty to the instrument will not perform or be able to perform in accordance with the terms of the instrument), hedging risk (the risk that a hedging strategy may not eliminate the risk that it is intended to offset), pricing risk (swaps may be difficult to value) and liquidity risk ( it may not be possible to liquidate a swap position at an advantageous time or price), each of which may result in significant and unanticipated losses to the Fund.

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.

Exchange-Traded Fund (ETF) Risk. An ETF’s share price may not track its specified market index (if any) and may trade below its NAV. Certain ETFs use a “passive” investment strategy and do not take defensive positions in volatile or declining markets. Other ETFs in which the Fund may invest are actively managed ETFs (i.e., they do not track a particular benchmark), which indirectly subjects the Fund to active management risk. An active secondary market in ETF shares may not develop or be maintained and may be halted or interrupted due to actions by its listing exchange, unusual market conditions or other reasons. There can be no assurance that an ETF’s shares will continue to be listed on an active exchange. In addition, shareholders bear both their proportionate share of the Fund’s expenses and similar expenses incurred through ownership of the ETF. There is a risk that ETFs in which the Fund invests may terminate due to extraordinary events. For example, any of the service providers to ETFs, such as the trustee or sponsor, may close or otherwise fail to perform their obligations to the ETF, and the ETF may not be able to find a substitute service provider. Also, certain ETFs may be dependent upon licenses to use various indexes as a basis for determining their compositions and/or otherwise to use certain trade names. If these licenses are terminated, the ETFs may also terminate. In addition, an ETF may terminate if its net assets fall below a certain amount.

Foreign Currency Risk. The performance of the Fund may be materially affected positively or negatively by foreign currency strength or weakness relative to the U.S. dollar, particularly if 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 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.

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. The performance of the Fund may be negatively impacted by fluctuations in a foreign currency’s strength or weakness relative to the U.S. dollar. 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 potentially confiscatory 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. 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; possible seizure, expropriation or nationalization of a company or its assets or

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the assets of a particular investor or category of investors; possible imposition of currency exchange controls; accounting, auditing and financial reporting standards that 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.

Forward Commitments on Mortgage-backed Securities (including Dollar Rolls) Risk. When purchasing mortgage-backed securities in the “to be announced” (TBA) market (MBS TBAs), the seller agrees to deliver mortgage-backed securities for an agreed upon price on an agreed upon date, but may make no guarantee as to the specific securities to be delivered. In lieu of taking delivery of mortgage-backed securities, the Fund could enter into dollar rolls, which are transactions in which the Fund sells securities to a counterparty and simultaneously agrees to purchase those or similar securities in the future at a predetermined price. Dollar rolls involve the risk that the market value of the securities the Fund is obligated to repurchase may decline below the repurchase price, or that the counterparty may default on its obligations. These transactions may also increase the Fund’s portfolio turnover rate. If the Fund reinvests the proceeds of the security sold, the Fund will also be subject to the risk that the investments purchased with such proceeds will decline in value (a form of leverage risk). MBS TBAs and dollar rolls are subject to counterparty risk.

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.

Hedging Transactions Risk. The Fund may invest in securities and utilize financial instruments for a variety of hedging purposes. Hedging transactions may limit the opportunity for gain if the value of the portfolio position should increase. There can be no assurance that the Fund will engage in hedging transactions at any given time, even under volatile market conditions, or that any hedging transactions the Fund engages in will be successful. Moreover, it may not be possible for the Fund to enter into a hedging transaction at a price sufficient to protect its assets. The Fund may not anticipate a particular risk so as to hedge against it.

Hedging against a decline in the value of a portfolio position does not eliminate fluctuations in the values of portfolio positions or prevent losses if the values of such positions decline, but establishes other positions designed to gain from those same developments, thus moderating the decline in the portfolio positions’ value. Such hedging transactions also limit the opportunity for gain if the value of the portfolio position should increase. Moreover, it may not be possible for the Fund to hedge against an exchange rate, interest rate or security price fluctuation that is so generally anticipated that the Fund is not able to enter into a hedging transaction at a price sufficient to protect its assets from the decline in value of the portfolio positions anticipated as a result of such fluctuations.

The Fund is not required to attempt to hedge portfolio positions and, for various reasons, may determine not to do so. Furthermore, the Fund may not anticipate a particular risk so as to hedge against it. While the Fund may enter into hedging transactions to seek to reduce risk, such transactions may result in a poorer overall performance for the Fund than if the Fund had not engaged in any such hedging transaction. In addition, the degree of correlation between price movements of the instruments used in a hedging strategy and price movements in the portfolio position being hedged may vary. For a variety of reasons, the Fund may not seek to establish a perfect correlation between such hedging instruments and the portfolio holdings being hedged. Such imperfect correlation may prevent the Fund from achieving the intended hedge or expose the Fund to risk of loss. The successful utilization of hedging and risk management transactions requires skills complementary to those needed in the selection of the Fund’s portfolio holdings. Moreover, it should be noted that a portfolio will always be exposed to certain risks that cannot be hedged, such as credit risk (relating both to particular securities and counterparties), liquidity risk and widening risk.

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High-Yield Securities Risk. Securities rated below investment grade (commonly called “high-yield” or “junk” bonds) and unrated securities of comparable quality tend to be more sensitive to credit risk than higher-rated securities and may experience greater price fluctuations in response to perceived changes in the ability of the issuing entity or obligor to pay interest and principal when due than to changes in interest rates. These investments are generally more likely to experience a default than higher-rated securities. High-yield securities are considered to be predominantly speculative with respect to the issuer’s capacity to pay interest and repay principal. These securities typically pay a premium — a higher interest rate or yield — because of the increased risk of loss, including default. High-yield securities may require a greater degree of judgment to establish a price, may be difficult to sell at the time and price the Fund desires, may carry high transaction costs, and also are generally less liquid than higher-rated securities. The securities ratings provided by third party rating agencies are based on analyses by these ratings agencies of the credit quality of the securities and may not take into account every risk related to whether interest or principal will be timely repaid. In adverse economic and other circumstances, issuers of lower-rated securities are more likely to have difficulty making principal and interest payments than issuers of higher-rated securities.

Interest Rate Risk. Interest rate risk is the risk of losses attributable to changes in interest rates. In general, if prevailing interest rates rise, the values of debt securities tend to fall, and if interest rates fall, the values of debt securities tend to rise. Changes in the value of a debt security usually will not affect the amount of income the Fund receives from it but will usually affect the value of the Fund's shares. In general, the longer the maturity or duration of a debt security, the greater its sensitivity to changes in interest rates. Interest rate declines also may increase prepayments of debt obligations, which, in turn, would increase prepayment risk. Similarly, a period of rising interest rates may negatively impact the Fund’s performance. Actions by governments and central banking authorities can result in increases in interest rates. Such actions may negatively affect the value of fixed-income securities held by the Fund, resulting in a negative impact on the Fund's performance and NAV.

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 a 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 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 one or more 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 one or more appropriate alternate underlying funds are not identified or available for investment timely or at all.

Investing in Wholly-Owned Subsidiary Risk. By investing in a Subsidiary, the Fund is indirectly exposed to the risks associated with the Subsidiary’s investments. The Fund’s Principal Risks may also apply to a Subsidiary in which the Fund invests (which are described in this prospectus). There can be no assurance that the investment objective of a Subsidiary will be achieved. No Subsidiary is registered under the 1940 Act and, except as otherwise noted in this prospectus, no Subsidiary is subject to the investor protections of the 1940 Act. However, the Fund wholly owns and controls any Subsidiary in which it invests, and the Fund and any Subsidiary in which it invests are managed by Columbia Management, making it unlikely that a Subsidiary will take action contrary to the interests of the Fund and its shareholders. The Fund’s Board has oversight responsibility for the investment activities of the Fund, including its investment in any Subsidiary, and the Fund’s role as sole shareholder of the Subsidiary. In managing a Subsidiary’s investment portfolio, Columbia Management, or the Subsidiary’s subadviser (if any), will manage the Subsidiary’s portfolio in accordance with the Fund’s investment policies and restrictions. Changes in the laws of the United States and/or the Cayman Islands, under which the Fund and any Subsidiary in which it

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invests, respectively, are organized, could result in the inability of the Fund and/or the Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Fund and its shareholders. For example, the Cayman Islands currently does not impose any income, corporate or capital gains tax, estate duty, inheritance tax, gift tax or withholding tax on any Subsidiary. If Cayman Islands law is changed and a Subsidiary is required to pay Cayman Island taxes, the investment returns of the Fund would likely decrease.

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.

Leverage Risk. Leverage occurs when the Fund increases its assets available for investment using borrowings, short sales, derivatives, or similar instruments or techniques. Because short sales involve borrowing securities and then selling them, the Fund’s short sales effectively leverage the Fund’s assets. The Fund's assets that are used as collateral to secure the Fund's obligations to return the securities sold short may decrease in value while the short positions are outstanding, which may force the Fund to use its other assets to increase the collateral. Leverage can create an interest expense that may lower the Fund's overall returns. Leverage presents the opportunity for increased net income and capital gains, but may also exaggerate the Fund’s volatility and risk of loss. There can be no guarantee that a leveraging strategy will be successful.

Liquidity Risk. Liquidity risk is the risk associated with a lack of marketability of investments which may make it difficult to sell the investment at a desirable time or price. Decreases in the number of financial institutions willing to make markets in the Fund’s investments or in their capacity or willingness to transact may increase the Fund’s exposure to this risk. Changing regulatory, market or other conditions or environments (for example, the interest rate or credit environments) may also adversely affect the liquidity of the Fund's investments. The Fund may have to accept a lower selling price for the holding, sell other investments, or forego another, more appealing investment opportunity. Judgment plays a larger role in valuing these investments as compared to valuing more liquid investments. Price volatility may be higher for illiquid investments as a result of, for example, the relatively less frequent pricing of such securities (as compared to 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. Price volatility, liquidity of the market and other factors can lead to an increase in Fund redemptions, which may negatively impact Fund performance and NAV, including, for example, if the Fund is forced to sell securities in a down market.

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. Security values 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 securities the Fund holds can be affected by changes or perceived changes in U.S. or foreign economies and financial markets, and the liquidity of these securities, among other factors. Although equity securities generally tend to have greater price volatility than debt securities, under certain market conditions, debt securities may have comparable or greater price volatility. In addition, stock prices may be sensitive to rising interest rates, as the cost of capital rises and borrowing costs increase.

Money Market Fund Investment Risk. An investment in a money market fund is not a bank deposit and is not insured or guaranteed by any bank, the FDIC or any other government agency. Although money market funds seek to preserve the value of investments at $1.00 per share, it is possible for the Fund to lose money by investing in money market funds. In addition to the fees and expenses that the Fund directly bears, the Fund indirectly bears the fees and expenses of any money market funds in which it invests, including affiliated money market funds. To the extent these fees and expenses, along with the fees and expenses of any other funds in which the Fund may invest, are expected to equal or exceed 0.01% of the Fund’s average daily net assets, they will be reflected in the Annual Fund Operating Expenses set forth in the table under “Fees and Expenses of the Fund.” By investing in a money market fund, the Fund will be exposed to the investment risks of the money market fund in direct proportion to such investment. The money market fund may not achieve its investment objective. The Fund, through its investment in the money market fund, may not achieve its investment objective. To the extent the Fund invests in instruments such as derivatives, the Fund may hold investments, which may be significant, in money market fund shares to cover its obligations resulting from the Fund’s investments in derivatives.

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Mortgage- and Other Asset-Backed Securities Risk.  The value of any mortgage-backed and other asset-backed securities held by the Fund may be affected by, among other things, changes or perceived changes in: interest rates; factors concerning the interests in and structure of the issuer or the originator of the mortgages or other assets; the creditworthiness of the entities that provide any supporting letters of credit, surety bonds or other credit enhancements; or the market's assessment of the quality of underlying assets. Mortgage-backed securities represent interests in, or are backed by, pools of mortgages from which payments of interest and principal (net of fees paid to the issuer or guarantor of the securities) are distributed to the holders of the mortgage-backed securities. Other types of asset-backed securities typically represent interests in, or are backed by, pools of receivables such as credit, automobile, student and home equity loans. Mortgage- and other asset-backed securities can have a fixed or an adjustable rate. Mortgage- and other asset-backed securities are subject to prepayment risk, which is the possibility that the underlying mortgage or other asset may be refinanced or prepaid prior to maturity during periods of declining or low interest rates, causing the Fund to have to reinvest the money received in securities that have lower yields. In addition, the impact of prepayments on the value of mortgage- and other asset-backed securities may be difficult to predict and may result in greater volatility. Rising or high interest rates tend to extend the duration of mortgage- and other asset-backed securities, making them more volatile and more sensitive to changes in interest rates. Payment of principal and interest on some mortgage-backed securities (but not the market value of the securities themselves) may be guaranteed (i) by the full faith and credit of the U.S. Government (in the case of securities guaranteed by the Government National Mortgage Association) or (ii) by its agencies, authorities, enterprises or instrumentalities (in the case of securities guaranteed by the Federal National Mortgage Association (FNMA) or the Federal Home Loan Mortgage Corporation (FHLMC)), which are not insured or guaranteed by the U.S. Government (although FNMA and FHLMC may be able to access capital from the U.S. Treasury to meet their obligations under such securities). Mortgage-backed securities issued by non-governmental issuers (such as commercial banks, savings and loan institutions, private mortgage insurance companies, mortgage bankers and other secondary market issuers) may be supported by various credit enhancements, such as pool insurance, guarantees issued by governmental entities, letters of credit from a bank or senior/subordinated structures, and may entail greater risk than obligations guaranteed by the U.S. Government, whether or not such obligations are guaranteed by the private issuer.

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).

Prepayment and Extension Risk. Prepayment risk is the risk that a loan, bond or other security or investment might be called or otherwise converted, prepaid or redeemed before maturity, and extension risk is the risk that the investment might not be called as expected. In the case of prepayment risk, if the investment is converted, prepaid or redeemed before maturity, particularly during a time of declining interest rates or spreads, the portfolio managers may not be able to invest the proceeds in other investments providing as high a level of income, resulting in a reduced yield to the Fund. Conversely, in the case of extension risk, as interest rates rise or spreads widen, the likelihood of prepayment decreases and the maturity of the investment may extend the life of the investment beyond the prepayment time. If the Fund's investments are locked in at a lower interest rate for a longer period of time, the portfolio managers may be unable to capitalize on securities with higher interest rates or wider spreads.

Quantitative Model Risk. The Fund may use quantitative methods to select investments. Securities or other investments selected using quantitative methods may perform differently from the market as a whole or from their expected performance for many reasons, including factors used in building the quantitative analytical framework, the weights placed on each factor, and changing sources of market returns, among others. Any errors or imperfections in the Fund portfolio manager’s quantitative analyses or models, or in the data on which they are based, could adversely affect the portfolio manager’s effective use of such analyses or models, which in turn could adversely affect the Fund’s performance. It is not possible or practicable for a manager to factor all relevant, available data into quantitative model forecasts and/or trading decisions. Quantitative managers will use their discretion to determine what data to gather with respect to an investment strategy and what data the models will take into account to produce forecasts that may have an impact on ultimate trading decisions. Shareholders should be aware that there is no guarantee that a quantitative manager will use any specific data or type of data in making trading decisions on behalf of the

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Fund, nor is there any guarantee that the data actually utilized in generating forecasts or making trading decisions on behalf of the Fund will be the most accurate data available or free from errors. There can be no assurance that these methodologies will enable the Fund to achieve its objective.

Short Positions Risk. The Fund may establish short positions which introduce more risk to the Fund than long positions (where the Fund owns the instrument or other asset) because the maximum sustainable loss on an instrument or other asset purchased (held long) is limited to the amount paid for the instrument or other asset plus the transaction costs, whereas there is no maximum price of the shorted instrument or other asset when purchased in the open market. Therefore, in theory, short positions have unlimited risk. The Fund’s use of short positions in effect “leverages” the Fund. Leverage potentially exposes the Fund to greater risks of loss due to unanticipated market movements, which may magnify losses and increase the volatility of returns. To the extent the Fund takes a short position in a derivative instrument or other asset, this involves the risk of a potentially unlimited increase in the value of the underlying instrument or other asset.

Sovereign Debt Risk. A sovereign debtor’s willingness or ability to repay principal and pay interest in a timely manner may be affected by a variety of factors, including its cash flow situation, the extent of its reserves, the availability of sufficient foreign exchange on the date a payment is due, the relative size of the debt service burden to the economy as a whole, the sovereign debtor’s policy toward international lenders, and the political constraints to which a sovereign debtor may be subject.

With respect to sovereign debt of emerging market issuers, investors should be aware that certain emerging market countries are among the largest debtors to commercial banks and foreign governments. At times, certain emerging market countries have declared moratoria on the payment of principal and interest on external debt. Certain emerging market countries have experienced difficulty in servicing their sovereign debt on a timely basis and that has led to defaults and the restructuring of certain indebtedness to the detriment of debtholders. Sovereign debt risk is increased for emerging market issuers.

Tax Risk. To qualify as a regulated investment company, the Fund must derive at least 90% of its gross income for each taxable year from sources treated as “qualifying income” under the Code. The Fund generally intends to gain exposure to certain asset classes through investments that give rise to qualifying income, by investing directly in instruments that the Fund believes give rise to qualifying income, or indirectly through its investment in one or more Subsidiaries, which, in turn, would invest in instruments providing exposure to such asset classes. The Fund intends to operate in such a manner that it will satisfy the 90% gross income requirement. In addition, the tax treatment of certain of the Fund’s investments and of the income and gain therefrom under the qualifying income test is uncertain, and an adverse determination or future guidance by the IRS (which determination or guidance may be retroactive) may affect whether the Fund has met the qualifying income test.

The Fund must also meet certain asset diversification requirements in order to qualify as a regulated investment company, including that, at the end of each quarter of the Fund’s taxable year, not more than 25% of the value of its total assets be invested in any issuer, or two or more issuers in which it owns a 20% voting stock interest (such as Subsidiaries) that are engaged in the same, similar or related trades or businesses (within the meaning of the diversification rules applicable to regulated investment companies).

If the Fund were to fail to appropriately limit its income from investments that do not give rise to qualifying income, the income or gain from certain of the Fund’s investments were to be recharacterized for purposes of the qualifying income test, or if the Fund were to fail to appropriately limit its investment in Subsidiaries, it is possible that the Fund would be unable to qualify as a regulated investment company and thus be ineligible (including retroactively) for the favorable tax treatment afforded to it as such for one or more years, which would adversely affect the value of the Fund.

U.S. Government Obligations Risk. While U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. Government, such securities are nonetheless subject to credit risk ( i.e. , the risk that the U.S. Government may be, or may be perceived to be, unable or unwilling to honor its financial obligations, such as making payments). Securities issued or guaranteed by federal agencies or authorities and U.S. Government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. Government. For example, securities issued by the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association and the Federal Home Loan Banks are neither insured nor guaranteed by the U.S. Government. These securities may be supported by the ability to borrow from the U.S. Treasury or only by the credit of the issuing agency, authority, instrumentality or enterprise and, as a result, are subject to greater credit risk than securities issued or guaranteed by the U.S. Treasury.

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Valuation Risk. The sales price the Fund (or an underlying fund or other investment vehicle) could receive for any particular investment may differ from the Fund’s (or an underlying fund’s or other investment vehicle’s) valuation of the investment, particularly for securities that trade in thin or volatile markets or that are valued using a fair value methodology that produces an estimate of the fair value of the security/instrument, which may prove to be inaccurate. Investors who purchase or redeem Fund shares on days when the Fund is holding securities or other instruments (or holding shares of underlying funds or other investment vehicles that have fair-valued securities or other instruments in their portfolios) may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the Fund (or underlying fund or other investment vehicle) had not fair-valued the security or instrument or had used a different valuation methodology. The value of foreign securities, certain fixed income securities and currencies, as applicable, may be materially affected by events after the close of the market on which they are valued, but before the Fund determines its net asset value.

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.

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 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 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 columbiamanagement.com.

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.

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More Information About the Fund (continued)

Investing in Affiliated Funds

The Investment Manager or an affiliate serves as investment adviser to mutual 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 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. 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 Fund’s SAI and its 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.

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Columbia Diversified Absolute Return Fund

More Information About the Fund (continued)

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 futures (e.g., index futures) or options on futures, for various purposes, including among others, investing in particular derivatives to achieve indirect investment exposures to a sector, country or region 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 (columbiamanagement.com) 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.

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.

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, 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 and are expressed as a percentage (expense ratio) of the Fund’s average net assets. The expense ratios reflect current fee arrangements. 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.

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More Information About the Fund (continued)

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 September 30, 2016, 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 Diversified Absolute Return Fund
Class A	1.71%
Class C	2.46%
Class I	1.31%
Class R4	1.46%
Class R5	1.36%
Class W	1.71%
Class Z	1.46%

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), 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, extraordinary expenses and any other expenses the exclusion of which is specifically approved by the Board. This agreement may be modified or amended only with approval from all parties.

Obtaining Recent Net Asset Value Per Share

The price you pay or receive when you buy, sell or exchange shares is the Fund's next determined net asset value (or NAV) per share for a given share class. The Fund calculates the NAV per share for each class of shares of the Fund at the end of each business day. For additional information on how the Fund calculates its NAV, see Buying, Selling and Exchanging Shares — Share Price Determination below.

You may obtain the current NAV of Fund shares at no cost by calling 800.345.6611 or by sending an e-mail to serviceinquiries@columbiamanagement.com.

Primary Service Providers

The Investment Manager, which also serves as the Fund’s administrator (the Administrator), 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.

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Columbia Diversified Absolute Return Fund

More Information About the Fund (continued)

The Investment Manager

Columbia Management Investment Advisers, LLC is located at 225 Franklin Street, Boston, MA 02110 and serves as investment adviser 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, fixed-income securities 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 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 for the Fund without first obtaining shareholder approval. The order permits the Fund to add or to change unaffiliated subadvisers or to change the fees paid to subadvisers from time to time without the expense and delays associated with obtaining shareholder approval of the change. 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 does not consider any other relationship it or its affiliates may have with a subadviser, and the Investment Manager discloses to the Board the nature of any material relationships it has with a subadviser or its affiliates. At present, the Investment Manager has not engaged any investment subadviser for the Fund.

With respect to the Fund, the Fund’s Board has approved a subadvisory agreement between the Investment Manager and Threadneedle International Limited (Threadneedle), an affiliate of the Investment Manager and an indirect wholly-owned subsidiary of Ameriprise Financial. At present, Threadneedle is not providing services to the Fund pursuant to the subadvisory agreement. A discussion regarding the basis for the Board approving the adoption of the subadvisory agreement with Threadneedle will be available in the Fund’s annual report to shareholders for the fiscal period ended May 31, 2015.

From time to time the Investment Manager may engage its investment advisory affiliates (Participating Affiliates) around the world to provide a variety of services such as, investment research, investment monitoring, trading and discretionary investment management (including portfolio management) to certain accounts managed by the Investment Manager, including the Fund. The Investment Manager expects to engage certain of its Threadneedle Investments affiliates to provide such services. These Participating Affiliates will provide services to the Investment Manager either pursuant to subadvisory agreements, personnel-sharing agreements or similar inter-company arrangements and the Investment Manager will bear any and all costs of such agreements. These Participating Affiliates, like the Investment Manager, are direct or indirect subsidiaries of Ameriprise Financial and are registered with the appropriate respective regulators in their home jurisdictions and, where required, the SEC and the CFTC in the United States.

Pursuant to some of these arrangements, certain employees of these Participating Affiliates may serve as “associated persons” of the Investment Manager and, in this capacity, subject to the oversight and supervision of the Investment Manager and consistent with the investment objectives, policies and limitations set forth in the Fund’s prospectus and SAI, may provide such services to the Fund on behalf of the Investment Manager.

The Fund pays the Investment Manager a fee for its investment advisory services. The fee is calculated as a percentage of the average daily net assets of the Fund, including assets invested in affiliated pooled investment vehicles (including mutual funds and exchange-traded funds); however, with respect to Fund assets invested in the affiliated underlying funds, the Investment Manager will waive the net management fees (investment advisory and administrative services fees, less reimbursements/waivers) of the affiliated underlying funds.

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More Information About the Fund (continued)

The Distributor

Shares of the Fund are distributed by Columbia Management Investment Distributors, Inc., which is located at 225 Franklin Street, Boston, MA 02110. The Distributor is a registered broker-dealer and an indirect, wholly-owned subsidiary of Ameriprise Financial. The Distributor and its affiliates may pay commissions, distribution and service fees and/or other compensation to entities, including Ameriprise Financial affiliates, for selling shares and providing services to investors.

The Transfer Agent

Columbia Management Investment Services Corp. is a registered transfer agent and wholly-owned subsidiary of Ameriprise Financial. The Transfer Agent is located at 225 Franklin Street, Boston, MA 02110, and its responsibilities include processing purchases, redemptions and exchanges of Fund shares, calculating and paying distributions, maintaining shareholder records, preparing account statements and providing customer service. The Transfer Agent has engaged DST Systems, Inc., including its affiliate, Boston Financial Data Services, to provide various shareholder services. In addition, the Transfer Agent enters into agreements with various financial intermediaries through which you may hold Fund shares, pursuant to which the Transfer Agent pays these financial intermediaries for providing certain shareholder services. The Fund generally pays the Transfer Agent a per account fee, pays a fee based on the assets invested through omnibus accounts and reimburses the Transfer Agent for certain out-of-pocket expenses.

Other Roles and Relationships of Ameriprise Financial and its Affiliates — Certain Conflicts of Interest

The Investment Manager, Distributor and Transfer Agent, all affiliates of Ameriprise Financial, provide various services to the Fund and other Columbia Funds for which they are compensated. Ameriprise Financial and its other affiliates may also provide other services to these funds and be compensated for them.

The Investment Manager and its affiliates may provide investment advisory and other services to other clients and customers substantially similar to those provided to the Columbia Funds. These activities, and other financial services activities of Ameriprise Financial and its affiliates, may present actual and potential conflicts of interest and introduce certain investment constraints.

Ameriprise Financial is a major financial services company, engaged in a broad range of financial activities beyond the mutual fund-related activities of the Investment Manager, including, among others, insurance, broker-dealer (sales and trading), asset management, banking and other financial activities. These additional activities may involve multiple advisory, financial, insurance and other interests in securities and other instruments, and in companies that issue securities and other instruments, that may be bought, sold or held by the Columbia Funds.

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.

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More Information About the Fund (continued)

Additional information about Ameriprise Financial and the types of conflicts of interest and other matters referenced above are 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.

About the Fund’s Wholly-Owned Subsidiary

The Fund may invest in one or more wholly-owned subsidiaries (for purposes of this section, referred to collectively as the Subsidiary).  The Subsidiary is an exempted company organized under the laws of the Cayman Islands. The Fund will invest in the Subsidiary in order to gain exposure to certain asset classes within the diversification and other limitations of Subchapter M of the U.S. Internal Revenue Code of 1986, as amended, applicable to “regulated investment companies.” The Fund must invest no more than 25% of its total assets in the Subsidiary as of the end of each quarter of its taxable year.

The Subsidiary is overseen by its own board of directors. However, the Fund’s Board oversees investment activities of the Subsidiary generally as if the Subsidiary’s investments were held directly by the Fund. The Investment Manager is responsible for the Subsidiary’s day-to-day business pursuant to a separate investment management services agreement between the Subsidiary and the Investment Manager. Under this agreement, the Investment Manager provides the Subsidiary with the same type of management services, under the same terms, as are provided to the Fund. The Subsidiary has entered into separate contracts for the provision of administrative and custody services with the same service providers who provide these services to the Fund. The Subsidiary will bear the fees and expenses incurred in connection with the advisory, administrative and custody services that it receives. The Fund expects that the expenses borne by the Subsidiary will not be material in relation to the value of the Fund’s assets.

In managing the Subsidiary’s investment portfolio, and in adhering to the Fund’s compliance policies and procedures, the Investment Manager will treat the assets of the Subsidiary generally as if the assets were held directly by the Fund. The Investment Manager will also treat the assets of the Subsidiary generally as if the assets were held directly by the Fund with respect to its adherence to the Fund’s investment policies and restrictions.

Please refer to the SAI for additional information about the organization and management of the Subsidiary.

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Columbia Diversified Absolute Return Fund

Choosing a Share Class

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 I.

Funds Contact Information

Additional information about the Funds can be obtained at columbiamanagement.com,* 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 Boston Financial, 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 for every share class. If you purchase shares of a Fund through a retirement plan or other product or program offered by your selling agent, not all share classes of the Fund may be made available to 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 expenses for each share class.

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

Each investor's personal situation is different and you may wish to discuss with your selling agent which share classes are available to you and which share class is appropriate for you.

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Columbia Diversified Absolute Return Fund

Choosing a Share Class (continued)

(c)

Actual front-end sales charges and CDSCs vary among the Funds. For more information on applicable sales charges, see Choosing a Share Class — Sales Charges and Commissions and for information about certain exceptions to these sales charges, see Choosing a Share Class — Reductions/Waivers of Sales Charges.

(d)

These are the maximum applicable distribution and/or service fees. Fee rates and fee components (i.e., the portion of a combined fee that is a distribution or service fee) may vary among Funds. Because these fees are paid out of Fund assets on an ongoing basis, over time these fees will increase the cost of your investment and may cost you more than paying other types of distribution and/or shareholder service fees. Although Class A shares of certain series of CFST I are subject to a combined distribution and service fee of up to 0.35%, these Funds currently limit the combined fee to 0.25%. Columbia Money Market Fund pays a distribution and service fee of up to 0.10% on Class A shares, up to 0.75% distribution fee and up to 0.10% service fee on Class B shares, up to 0.75% distribution fee on Class C shares, and 0.10% distribution and service fees on Class W shares. Columbia AMT-Free Intermediate Muni Bond Fund, Columbia High Yield Municipal Fund and Columbia Tax-Exempt Fund pay a service fee of up to 0.20% on Class A, Class B and Class C shares. Columbia AMT-Free Intermediate Muni Bond Fund pays a distribution fee of up to 0.65% on Class B and Class C shares. For more information on distribution and service fees, see Choosing a Share Class — Distribution and Service Fees.

(e)

The following Funds are not subject to a front-end sales charge or a CDSC on Class A shares: Columbia Money Market Fund, Columbia Large Cap Index Fund, Columbia Large Cap Enhanced Core Fund, Columbia Mid Cap Index Fund and Columbia Small Cap Index Fund. Columbia U.S. Treasury Index Fund is not subject to a CDSC.

(f)	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 B Shares . The Funds no longer accept investments from new or existing investors in Class B shares, except through reinvestment of dividend and/or capital gain distributions by existing Class B shareholders, or a permitted exchange.

•   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 R5 Shares . Shareholders with Class R5 accounts funded before November 8, 2012 who do not satisfy the current eligibility criteria for Class R5 shares may not establish new Class R5 accounts but may continue to make additional purchases of Class R5 shares in existing accounts. In addition, investment advisory programs and similar programs that opened a Class R5 account as of May 1, 2010 and continuously hold Class R5 shares in such account after such date, may generally not only continue to make additional purchases of Class R5 shares but also open new Class R5 accounts for such pre-existing programs and add new shareholders in the program.

•   Class T Shares. Shareholders with Class T accounts who received, and have continuously held, 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.

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

•   Class Z Shares . Effective March 29, 2013, selling agents that clear Fund share transactions through designated selling agents and their mutual fund trading platforms that have been given specific written notice from the Transfer Agent of the termination of their eligibility for new purchases of Class Z shares and omnibus retirement plans are no longer permitted to establish new Class Z accounts, subject to certain exceptions. Omnibus retirement plans that opened and, subject to exceptions, funded a Class Z account as of close of business on March 28, 2013 and continuously hold Class Z shares in such account after such date, may generally continue to make additional purchases of Class Z shares, open new Class Z 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 Z accounts. Accounts of selling agents (other than omnibus retirement plans) that clear Fund share transactions for their client or customer accounts through designated selling agents and their mutual fund trading platforms are not permitted to establish new Class Z accounts or make additional purchases of Class Z shares (other than through reinvestment of distributions).

(g)

Timing of conversion and CDSC schedules will vary depending on the Fund and the date of your original purchase of Class B shares. For more information on the conversion of Class B shares to Class A shares, see Choosing a Share Class — Sales Charges and Commissions. Class B shares of Columbia Short Term Municipal Bond Fund do not charge a CDSC and do not convert to Class A shares.

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

Sales Charges and Commissions

Sales charges, commissions and distribution and service fees (discussed in a separate sub-section below) compensate selling agents (typically your financial advisor) for selling shares to you and for maintaining and servicing the shares held in your account with them. These charges, commissions and fees are intended to provide incentives for selling agents to provide such services. Depending on which share class you choose you will pay these charges either 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 increased ongoing fees.

Whether the ultimate cost is higher for one class over another depends on the amount you invest, how long you hold your shares and whether you are eligible for reduced or waived sales charges. 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 account your share class eligibility and the value of accounts that you are eligible to include for the right

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Choosing a Share Class (continued)

of accumulation, which may reduce or eliminate otherwise applicable sales charges. See Choosing as Share Class – Reductions/Waivers of Sales Charges . We encourage you to consult with a financial advisor who can help you with your investment decisions.

Class A Shares — Front-End Sales Charge

You'll pay a front-end sales charge when you buy Class A shares (other than shares of Columbia Money Market Fund and certain other Funds), resulting in a smaller dollar amount being invested in a Fund than the purchase price you pay, unless you qualify for a waiver of the sales charge or you buy the shares through reinvested distributions. For more information, see Choosing a Share Class — Reductions/Waivers of Sales Charges.

The Distributor receives the sales charge and re-allows (or pays) a portion of the sales charge to the selling agent 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 selling agent). Sales charges vary depending on the amount of your purchase.

■	The net asset value (or 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 that applies.

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

■	depends on the amount you're 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 selling agent notifies the Fund).

    

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 selling agents as a % of the offering price
Equity Funds, Columbia Absolute Return Emerging Markets Macro Fund, Columbia Absolute Return Enhanced Multi-Strategy Fund, Columbia Adaptive Alternatives Fund, Columbia Adaptive Risk Allocation 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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39