Columbia Funds Series Trust I

Supplement dated December 20, 2017

to the Prospectus and Summary Prospectus, each as supplemented, of the following fund (the Fund):

Fund	Prospectus and Summary Prospectus Dated
Columbia Funds Series Trust I
Columbia New York Tax-Exempt Fund	3/1/2017

On December 13, 2017, the Fund's Board of Trustees approved changes to the Fund's name, investment objective, and principal investment strategies, which included eliminating the Fund's current policy that limits investment in high yield investments, including "junk" bonds, to 25% of the Fund's total net assets. Effective on or about January 22, 2018 (the Effective Date), the Fund’s name is changed to Columbia Strategic New York Municipal Income Fund and all references in the Prospectus to Columbia New York Tax-Exempt Fund are hereby deleted and replaced with Columbia Strategic New York Municipal Income Fund. In addition, as of the Effective Date, the changes described in this Supplement are hereby made to the Fund’s Prospectus.

The “Investment Objective” in the “Summary of the Fund” section is hereby superseded and replaced with the following:

Columbia Strategic New York Municipal Income Fund (the Fund) seeks total return, with a focus on income exempt from federal income tax and New York individual income tax and capital appreciation.

The information under the caption "Principal Investment Strategies" in the "Summary of the Fund" section is hereby superseded and replaced with the following: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 80% of its net assets (including the amount of any borrowings for investment purposes) in municipal bonds that pay interest exempt from U.S. federal income tax (including the federal alternative minimum tax) and New York individual income tax. The Fund may invest in municipal debt instruments of any duration, maturity and credit quality, including below investment grade debt (commonly referred to as “high yield” investments or “junk” bonds). The Fund may invest up to 20% of its net assets in debt instruments that generate income subject to federal income tax, including the federal alternative minimum tax.

For purposes of the Fund’s 80% investment policy, these bonds and other debt instruments include those issued by or on behalf of the State of New York and its political subdivisions, agencies, authorities and instrumentalities, as well as by or on behalf of other qualified issuers, including those of U.S. territories, commonwealths and possessions, such as Guam, Puerto Rico and the U.S. Virgin Islands. The Fund may also invest in securities of other open-end or closed-end investment companies, including exchange-traded funds and municipal bond money market funds, that invest primarily in the types of debt instruments in which the Fund may invest directly. Given the flexible investment approach of the Fund, its maturity, duration, credit quality and sector allocations may fluctuate.

The Fund may invest in debt instruments of any maturity and does not seek to maintain a particular dollar-weighted average maturity.

The Fund may also invest in zero-coupon bonds.

The Fund may invest in derivatives, such as futures (including interest rate futures and other bond futures) for purposes of yield curve exposure and for hedging purposes, and inverse floaters, for the purpose of enhancing income.

The Fund is non-diversified, which means that it can invest a greater percentage of its assets in the securities of fewer issuers than can a diversified fund.

The information under the caption "Principal Risks" in the "Summary of the Fund" section is hereby modified to add the following Principal Risks:

Derivatives Risk. Derivatives may involve significant risks. Derivatives are financial instruments with a value in relation to, or derived from, the value of an underlying asset(s) or other reference, such as an index, rate or other economic indicator (each an underlying reference). Derivatives may include those that are privately placed or otherwise exempt from SEC registration, including certain Rule 144A eligible securities. Derivatives could result in Fund losses if the underlying reference does not perform as anticipated. Use of derivatives is a highly specialized activity that can involve investment techniques, risks, and tax planning different from those associated with more traditional investment instruments. The Fund’s derivatives strategy may not be successful and use of certain derivatives could result in substantial, potentially unlimited, losses to the Fund regardless of the Fund’s actual investment. A relatively small movement in the price, rate or other economic indicator associated with the underlying reference may result in substantial loss for the Fund. Derivatives may be more volatile than other types of investments. The value of derivatives may be influenced by a variety of factors, including national and international political and economic developments. Potential changes to the regulation of the derivatives markets may make derivatives more costly, may limit the market for derivatives, or may otherwise adversely affect the value or performance of derivatives. Derivatives can increase the Fund’s risk exposure to underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

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futures contract markets are highly volatile, and futures contracts may be illiquid. Futures exchanges may limit fluctuations in futures contract prices by imposing a maximum permissible daily price movement. The Fund may be disadvantaged if it is prohibited from executing a trade outside the daily permissible price movement. At or prior to maturity of a futures contract, the Fund may enter into an offsetting contract and may incur a loss to the extent there has been adverse movement in futures contract prices. The liquidity of the futures markets depends on participants entering into offsetting transactions rather than making or taking delivery. To the extent participants make or take delivery, liquidity in the futures market could be reduced. Because of the low margin deposits normally required in futures trading, it is possible that the Fund may employ a high degree of leverage in the portfolio. As a result, a relatively small price movement in a futures contract may result in substantial losses to the Fund, exceeding the amount of the margin paid. For certain types of futures contracts, losses are potentially unlimited. Futures markets are highly volatile and the use of futures may increase the volatility of the Fund’s NAV. Futures contracts executed (if any) on foreign exchanges may not provide the same protection as U.S. exchanges. Futures contracts can increase the Fund’s risk exposure to underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while also exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

Derivatives Risk – Inverse Floaters Risk. Inverse variable or floating rate obligations, sometimes referred to as inverse floaters, are a type of over-the-counter derivative debt instrument with a variable or floating coupon rate that moves in the opposite direction of an underlying reference, typically short-term interest rates. While inverse floaters tend to provide more income than similar term and credit quality fixed-rate bonds, they also exhibit greater volatility in price movement, which could result in significant losses for the Fund. An inverse floater may have the effect of investment leverage to the extent that its coupon rate varies by a magnitude that exceeds the magnitude of the change in the index or reference rate of interest, which could result in increased losses for the Fund. Inverse floaters can increase the Fund’s risk exposure to underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while also exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

Exchange-Traded Fund (ETF) Risk. Investments in ETFs have unique characteristics, including, but not limited to, the expense structure and additional expenses associated with investing in ETFs. 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 indirectly the ETF’s expenses, incurred through the Fund’s ownership of the ETF. Because the expenses and costs of an underlying ETF are shared by its investors, redemptions by other investors in the ETF could result in decreased economies of scale and increased operating expenses for such ETF. The ETFs may not achieve their investment objective. The Fund, through its investment in ETFs, may not achieve its investment objective.

Investing in Other Funds Risk. The Fund’s investment in other funds (affiliated and/or unaffiliated funds, including exchange-traded funds (ETFs)) subjects the Fund to the investment performance (positive or negative) and risks of the underlying funds in direct proportion to the Fund’s investment therein. In addition, investments in ETFs have unique characteristics, including, but not limited to, the expense structure and additional expenses associated with investing in ETFs. The performance of the underlying funds could be adversely affected if other investors in the same underlying funds make relatively large investments or redemptions in such underlying funds. The Fund, and its shareholders, indirectly bear a portion of the expenses of any funds in which the Fund invests. Because the expenses and costs of an underlying fund are shared by its investors, redemptions by other investors in the underlying funds could result in decreased economies of scale and increased operating expenses for such underlying funds. Also, to the extent that the Fund is constrained/restricted from investing (or investing further) in a particular underlying fund for one or more reasons (e.g., underlying fund capacity constraints or regulatory restrictions) or if the Fund chooses to sell its investment in an underlying fund because of poor investment performance or for other reasons, the Fund may have to invest in other underlying funds, including less desirable funds – from a strategy or investment performance standpoint – which could have a negative impact on Fund performance. In addition, Fund performance could be negatively impacted if an appropriate alternate underlying fund does not present itself in a timely manner or at all. The underlying funds may not achieve their investment objective. The Fund, through its investment in underyling funds, may not achieve its investment objective.

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. Certain money market funds float their NAV while others seek to preserve the value of investments at a stable NAV (typically, $1.00 per share). An investment in a money market fund, even an investment in a fund seeking to maintain a stable NAV per share, is not guaranteed and it is possible for the Fund to lose money by investing in these and other types of money market funds. If the liquidity of a money market fund’s portfolio deteriorates below certain levels, the money market fund may suspend redemptions (i.e., impose a redemption gate) and thereby prevent the Fund from selling its investment in the money market fund or impose a fee of up to 2% on amounts the Fund redeems from the money market fund (i.e., impose a liquidity fee). These measures may result in an investment loss or prohibit the Fund from redeeming shares when the Investment Manager would otherwise redeem shares. 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. 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. 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. Money market funds and the securities they invest in are subject to comprehensive regulations. The enactment of new legislation or regulations, as well as changes in interpretation and enforcement of current laws, may affect the manner of operation, performance and/or yield of money market funds.

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The rest of the section remains the same.

The “Investment Objective” in the “More Information About the Fund” section is hereby superseded and replaced with the following:

Columbia Strategic New York Municipal Income Fund (the Fund) seeks total return, with a focus on income exempt from federal income tax and New York individual income tax and capital appreciation. The Fund’s investment objective is not a fundamental policy and may be changed by the Fund’s Board of Trustees without shareholder approval.

Because any investment involves risk, there is no assurance the Fund’s investment objective will be achieved.

The information under the caption “Principal Investment Strategies” in the “More Information About the Fund” section of the Fund's Prospectus is hereby superseded and replaced with the following:

The Fund may invest in debt instruments 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. Duration measures the sensitivity of bond prices to changes in interest rates. The longer the duration of a bond, the more sensitive it will be to changes in interest rates. For example, a three-year duration means a bond is expected to decrease in value by 3% if interest rates rise 1% and increase in value by 3% if interest rates fall 1%.

The Fund may also invest in zero-coupon bonds.

The Fund is non-diversified, which means that it can invest a greater percentage of its assets in the securities of fewer issuers than can a diversified fund.

In pursuit of the Fund’s objective, Columbia Management Investment Advisers, LLC (the Investment Manager) chooses investments by:

■	Considering opportunities and risks in municipal obligations given current and expected interest rates;
■	Identifying municipal obligations across the credit quality spectrum, including non-rated and below investment grade securities that fit the Fund’s investment strategy; and/or
■	Seeking to identify investments that contribute to portfolio diversification. The Investment Manager will weight certain credit sectors, maturities, states or bond structures based on the Investment Manager’s expectations for growth and expected market trends.

In evaluating whether to sell a security, the Investment Manager considers, among other factors, whether in its view:

■	The security is overvalued relative to alternative investments;
■	The issuer’s credit rating has declined or the Investment Manager expects a decline (the Fund may continue to own securities that are downgraded until the Investment Manager believes it is advantageous to sell);
■	Political, economic, or other events could affect the issuer’s performance;
■	The Investment Manager believes that it has identified a more attractive opportunity; and/or
■	The issuer or the security no longer meets the security selection criteria described above.

The Fund’s investment policy with respect to 80% of its net assets may not be changed without shareholder approval.

The information under the caption “Principal Risks” in the “More Information About the Fund” section is hereby modified to add the following Principal Risks:

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Derivatives Risk. Derivatives may involve significant risks. Derivatives are financial instruments, traded on an exchange or in the over-the-counter (OTC) markets, with a value in relation to, or derived from, the value of an underlying asset(s) (such as a security, commodity or currency) or other reference, such as an index, rate or other economic indicator (each an underlying reference). Derivatives may include those that are privately placed or otherwise exempt from SEC registration, including certain Rule 144A eligible securities. Derivatives could result in Fund losses if the underlying reference does not perform as anticipated. Use of derivatives is a highly specialized activity that can involve investment techniques, risks, and tax planning different from those associated with more traditional investment instruments. The Fund’s derivatives strategy may not be successful and use of certain derivatives could result in substantial, potentially unlimited, losses to the Fund regardless of the Fund’s actual investment. A relatively small movement in the price, rate or other economic indicator associated with the underlying reference may result in substantial loss for the Fund. Derivatives may be more volatile than other types of investments. Derivatives can increase the Fund’s risk exposure to underlying references and their attendant risks, including the risk of an adverse credit event associated with the underlying reference (credit risk), the risk of an adverse movement in the value, price or rate of the underlying reference (market risk), the risk of an adverse movement in the value of underlying currencies (foreign currency risk) and the risk of an adverse movement in underlying interest rates (interest rate risk). Derivatives may expose the Fund to additional risks, including the risk of loss due to a derivative position that is imperfectly correlated with the underlying reference it is intended to hedge or replicate (correlation risk), the risk that a counterparty will fail to perform as agreed (counterparty risk), the risk that a hedging strategy may fail to mitigate losses, and may offset gains (hedging risk), the risk that losses may be greater than the amount invested (leverage risk), the risk that the Fund may be unable to sell an investment at an advantageous time or price (liquidity risk), the risk that the investment may be difficult to value (pricing risk), and the risk that the price or value of the investment fluctuates significantly over short periods of time (volatility risk). The value of derivatives may be influenced by a variety of factors, including national and international political and economic developments. Potential changes to the regulation of the derivatives markets may make derivatives more costly, may limit the market for derivatives, or may otherwise adversely affect the value or performance of derivatives.

Derivatives Risk – Futures Contracts Risk. A futures contract is an exchange-traded derivative transaction between two parties in which a buyer (holding the “long” position) agrees to pay a fixed price (or rate) at a specified future date for delivery of an underlying reference from a seller (holding the “short” position). The seller hopes that the market price on the delivery date is less than the agreed upon price, while the buyer hopes for the contrary. Certain futures contract markets are highly volatile, and futures contracts may be illiquid. Futures exchanges may limit fluctuations in futures contract prices by imposing a maximum permissible daily price movement. The Fund may be disadvantaged if it is prohibited from executing a trade outside the daily permissible price movement. At or prior to maturity of a futures contract, the Fund may enter into an offsetting contract and may incur a loss to the extent there has been adverse movement in futures contract prices. The liquidity of the futures markets depends on participants entering into offsetting transactions rather than making or taking delivery. To the extent participants make or take delivery, liquidity in the futures market could be reduced. Positions in futures contracts may be closed out only on the exchange on which they were entered into or through a linked exchange, and no secondary market exists for such contracts. Futures positions are marked to market each day and variation margin payment must be paid to or by the Fund. Because of the low margin deposits normally required in futures trading, it is possible that the Fund may employ a high degree of leverage in the portfolio. As a result, a relatively small price movement in a futures contract may result in substantial losses to the Fund, exceeding the amount of the margin paid. For certain types of futures contracts, losses are potentially unlimited. Futures markets are highly volatile and the use of futures may increase the volatility of the Fund’s NAV. Futures contracts executed (if any) on foreign exchanges may not provide the same protection as U.S. exchanges. Futures contracts can increase the Fund’s risk exposure to underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while also exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

■

A bond (or debt instrument) future is a derivative that is an agreement for the contract holder to buy or sell a bond or other debt instrument, a basket of bonds or other debt instrument, or the bonds or other debt instruments in an index on a specified date at a predetermined price. The buyer (long position) of a bond future is obliged to buy the underlying reference at the agreed price on expiry of the future.

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An interest rate future is a derivative that is an agreement whereby the buyer and seller agree to the future delivery of an interest-bearing instrument on a specific date at a pre-determined price. Examples include Treasury-bill futures, Treasury-bond futures and Eurodollar futures.

Derivatives Risk – Inverse Floaters Risk. Inverse variable or floating rate obligations, sometimes referred to as inverse floaters, are a type of over-the-counter derivative debt instrument with a variable or floating coupon rate that moves in the opposite direction of an underlying reference, typically short-term interest rates. As short-term interest rates go down, the holders of the inverse floaters receive more income and, as short-term interest rates go up, the holders of the inverse floaters receive less income. Variable rate securities provide for a specified periodic adjustment in the coupon rate, while floating rate securities have a coupon rate that changes whenever there is a change in a designated benchmark index or the issuer’s credit rating. While inverse floaters tend to provide more income than similar term and credit quality fixed-rate bonds, they also exhibit greater volatility in price movement, which could result in significant losses for the Fund. An inverse floater may have the effect of investment leverage to the extent that its coupon rate varies by a magnitude that exceeds the magnitude of the change in the index or reference rate of interest, which could result in increased losses for the Fund. There is a risk that the current interest rate on variable and floating rate instruments may not accurately reflect current market interest rates or adequately compensate the holder for the current creditworthiness of the issuer. Some inverse floaters are structured with

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liquidity features and may include market-dependent liquidity features that may expose the Fund to greater liquidity risk. Inverse floaters can increase the Fund’s risk exposure to underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while also exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

Exchange-Traded Fund (ETF) Risk. Investments in ETFs have unique characteristics, including, but not limited to, the expense structure and additional expenses associated with investing in ETFs. 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, indirectly, the ETF’s expenses, incurred through the Fund’s ownership of the ETF. Because the expenses and costs of an underlying ETF are shared by its investors, redemptions by other investors in the ETF could result in decreased economies of scale and increased operating expenses for such ETF. These transactions might also result in higher brokerage, tax or other costs for the ETF. This risk may be particularly important when one investor owns a substantial portion 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.

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

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. Certain money market funds float their NAV while others seek to preserve the value of investments at a stable NAV (typically $1.00 per share). An investment in a money market fund, even an investment in a fund seeking to maintain a stable NAV per share, is not guaranteed and it is possible for the Fund to lose money by investing in these and other types of money market funds. If the liquidity of a money market fund’s portfolio deteriorates below certain levels, the money market fund may suspend redemptions (i.e., impose a redemption gate) and thereby prevent the Fund from selling its investment in the money market fund or impose a fee of up to 2% on amounts the Fund redeems from the money market fund (i.e., impose a liquidity fee). These measures may result in an investment loss or prohibit the Fund from redeeming shares when the Investment Manager would otherwise redeem shares. 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. Money market funds and the securities they invest in are subject to comprehensive regulations. The enactment of new legislation or regulations, as well as changes in interpretation and enforcement of current laws, may affect the manner of operation, performance and/or yield of money market funds.

The rest of the section remains the same.

Shareholders should retain this Supplement for future reference.

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