Columbia Funds Series Trust

Supplement dated February 4, 2015

to the Prospectus, as supplemented, of the following fund:

Fund	Prospectus Dated
Columbia Funds Series Trust
Columbia Marsico International Opportunities Fund	6/25/2014

Effective on or about May 1, 2015 (the Effective Date), Columbia Management Investment Advisers, LLC provides day-to-day management of the Fund's portfolio and the Fund’s name will change to Columbia International Opportunities Fund. Accordingly, on the Effective Date, all references in the Prospectus to Columbia Marsico International Opportunities Fund are deleted and replaced with Columbia International Opportunities Fund. In addition, the following changes are hereby made in the Fund’s Prospectus:

As of the Effective Date, the information under the caption "Principal Investment Strategies" in the "Summary of the Fund" section is hereby superseded and replaced with the following:

Under normal circumstances, the Fund invests at least 65% of its total assets in equity securities (including common stock, preferred stock, and depositary receipts) of companies located in at least three countries other than the United States, including emerging market countries. The Fund invests in companies that are believed to have the potential for growth. The Fund typically employs a focused portfolio investing style, which results in fewer holdings than a fund that seeks to achieve its investment objective by investing in a greater number of issuers.

The Fund may invest in derivatives, including futures and forward foreign currency contracts, in an effort to enhance returns, to hedge existing positions, to manage the Fund’s currency and overall risk exposure, to increase market or other exposure, and/or to increase investment flexibility (including using the derivative as a substitute for a position in an underlying security, currency, asset, or other instrument or reference). Derivatives may be used by the Fund to obtain net long and/or net negative (short) exposure to a security, currency, asset, or other instrument or reference.

The Fund may invest in companies involved in initial public offerings, tender offers, mergers, other corporate restructurings and other special situations.

As of the Effective Date, the information under the caption "Principal Risks” in the "Summary of the Fund" section is hereby revised to delete references to Frequent Trading Risk, Sector Risk and Small- and Mid-Cap Company Securities Risk and to add the following:

Depositary Receipts Risk. Depositary receipts are receipts issued by a bank or trust company reflecting ownership of underlying securities issued by foreign companies. Some foreign securities are traded in the form of American Depositary Receipts (ADRs). Depositary receipts involve risks similar to the risks associated with investments in foreign securities, including those of the particular country, which may be related to the particular political, regulatory, economic, social and other conditions or events occurring in the country and fluctuations in its currency, as well as market risk tied to the underlying foreign company. In addition, ADR holders may have limited voting rights and may not have the same rights afforded typical company stockholders in the event of a corporate action such as an acquisition, merger or rights offering and may experience difficulty in receiving company stockholder communications.

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/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/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

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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.

Focused Portfolio Risk. Because the Fund may invest in a limited number of companies, the Fund as a whole is subject to greater risk of loss if any of those securities decline in price.

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

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

The rest of the section remains the same.

As of the Effective Date, the information under the caption "Fund Management” in the "Summary of the Fund" section is hereby superseded and replaced with the following:

Investment Manager: Columbia Management Investment Advisers, LLC

Portfolio Manager	Title	Role with Fund	Managed Fund Since
Simon Haines, CFA	Fund Manager	Portfolio Manager	May 2015
William Davies	Head of Global Equities and Deputy Head of Equities of Threadneedle	Deputy Portfolio Manager	May 2015
David Dudding, CFA	Fund Manager	Deputy Portfolio Manager	May 2015

As of the Effective Date, the information under the caption “Principal Investment Strategies” in the "More Information About the Fund" section is hereby superseded and replaced with the following:

The Fund may invest in companies involved in initial public offerings, tender offers, mergers, other corporate restructurings and other special situations.

Columbia Management Investment Advisers, LLC (the Investment Manager) chooses investments for the Fund by:

■	Deploying an integrated approach to equity research that incorporates regional analyses, an international sector strategy, and stock specific perspectives;
■	Conducting detailed research on companies in a consistent strategic and macroeconomic framework;

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■	Looking for catalysts of change and identifying the factors driving markets, which will vary over economic and market cycles; and
■	Implementing rigorous risk control processes that seek to ensure that the risk and return characteristics of the Fund’s portfolio are consistent with established portfolio management parameters.

A number of factors may prompt the portfolio management team to sell securities. A sale may result from a change in the composition of the Fund’s benchmark or a change in sector strategy. A sale may also be prompted by factors specific to a stock, such as valuation or company fundamentals.

As of the Effective Date, the information under the caption "Principal Risks” in the "More Information About the Fund" section is hereby revised to delete references to Frequent Trading Risk, Sector Risk and Small- and Mid-Cap Company Securities Risk and to add the following:

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/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/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 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

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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.

Focused Portfolio Risk. The Fund, because it may invest in a limited number of companies, may have more volatility in its NAV and is considered to have more risk than a fund that invests in a greater number of companies because changes in the value of a single security may have a more significant effect, either negative or positive, on the Fund’s NAV. To the extent the Fund invests its assets in fewer securities, the Fund is subject to greater risk of loss if any of those securities decline in price.

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

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

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

The rest of the section remains the same.

As of the Effective Date, the fifth paragraph under the caption "The Investment Manager" in the "More Information About the Fund — Primary Service Providers" section is hereby superseded and replaced with the following:

At present, the Investment Manager has not engaged any investment subadviser for the Fund.

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

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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 Commodity Futures Trading Commission 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.

As of the Effective Date, the caption and information under "Subadviser" in the "More Information About the Fund — Primary Service Providers" section is hereby deleted.

As of the Effective Date, the information under the caption "Portfolio Managers" in the "More Information About the Fund — Primary Service Providers" section is hereby superseded and replaced with the following:

Portfolio Managers

Information about the portfolio managers primarily responsible for overseeing the Fund’s investments is shown below. The SAI provides additional information about the portfolio managers, including information relating to compensation, other accounts managed by the portfolio managers and ownership by the portfolio managers of Fund shares.

Portfolio Manager	Title	Role with Fund	Managed Fund Since
Simon Haines, CFA	Fund Manager	Portfolio Manager	May 2015
William Davies	Head of Global Equities and Deputy Head of Equities of Threadneedle	Deputy Portfolio Manager	May 2015
David Dudding, CFA	Fund Manager	Deputy Portfolio Manager	May 2015

Mr. Haines joined Threadneedle in 1999 as a trainee UK fund manager, progressing to fund manager effective January 2005. Mr. Haines began his investment career in 1999 and earned a degree from Oxford University.

Mr. Davies joined Threadneedle in 1994. Prior to assuming his current roles, Mr. Davies was Head of European Equities. Prior to joining Threadneedle, Mr. Davies worked for Eagle Star Investments and Hambros Bank. At Hambros Bank Mr. Davies was a European Investment Manager and led the European Equity team. Mr. Davies began his investment career in 1984 and earned a B.A (Hons) in Economics from Exter University.

Mr. Dudding joined Threadneedle in 1999 as an analyst. Mr. Dudding began his investment career in 1999 and earned a Modern History degree and a European Politics Masters degree from Oxford University.

Shareholders should retain this Supplement for future reference.

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