Prospectus by Investment Company (Form 497)

Supplement dated May 20, 2026

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

Fund	Prospectus Dated
Columbia Funds Series Trust I
Columbia Adaptive Risk Allocation Fund	10/1/2025

The disclosure for Columbia Commodity Strategy Fund in the Appendix B - Underlying Funds - Investment Objectives and Strategies is deleted and replaced with the following:

Columbia Commodity Strategy Fund

Columbia Commodity Strategy Fund (the Fund) seeks to provide shareholders with total return.

Under normal circumstances, the Fund seeks to maintain substantial economic exposure to the performance of the commodities markets. The Fund invests, directly or indirectly, in a portfolio of commodity-linked investments, such as commodity-linked futures, structured notes and/or swaps, that are designed to provide long and short exposures to the investment return of assets that trade in the commodities markets, without investing directly in physical commodities. A substantial portion of the Fund's net assets will also be invested in a portfolio of fixed income securities rated investment-grade or, if unrated, deemed of comparable quality, which will consist primarily of: (i) U.S. Government securities (including U.S. Government agency securities), corporate debt securities, mortgage-backed securities and/or asset-backed securities; and/or (ii) shares of an affiliated money market fund. In addition to investing in these holdings for their income-producing potential, these holdings will be designated by the Fund, as necessary, to serve as collateral with respect to the Fund's commodity-linked investments.

The Fund primarily expects to gain exposure to the commodities markets by investing up to 25% of its total assets in a wholly-owned subsidiary of the Fund organized as a company under the laws of the Cayman Islands (the Subsidiary). The Subsidiary's commodity-linked investments are expected to produce leveraged exposure to the performance of the commodities markets. It is expected that the gross notional value of the Fund's (including the Subsidiary's) commodity-linked investments will be equivalent to at least 90% of the Fund's net assets. Like the Fund, the Subsidiary will not invest directly in physical commodities. The Subsidiary also invests in investment-grade fixed income securities and shares of an affiliated money market fund for investment purposes or to serve as collateral for its commodity-linked investments. The Fund's investment in the Subsidiary permits it to gain exposure to the commodities markets in a potentially tax-efficient manner. The Subsidiary has the same investment objective as the Fund and, like the Fund, is managed by Columbia Management Investment Advisers, LLC (Columbia Management or the Investment Manager).

The Fund may invest in derivatives, including futures contracts (including commodity-linked futures and interest rate futures), options contracts (including options on futures contracts), structured investments (including commodity-linked structured notes) and swaps (including commodity-linked swaps) to increase, modify, reduce or short commodity market positions or exposures. Actual exposures will vary over time based on factors such as market movements and assessments of market conditions by the Fund's portfolio managers. The Fund may engage in derivative transactions on both U.S. and foreign exchanges or in the "over-the-counter" (OTC) market. The Fund may at times emphasize one or more sectors in selecting its investments, including the agricultural, energy and precious metals sectors.

The Fund may invest in privately placed and other securities or instruments that are purchased and sold pursuant to Rule 144A or other exemptions under the Securities Act of 1933, as amended, subject to certain regulatory restrictions.

In constructing the Fund's fixed-income portfolio, the Investment Manager seeks to identify a portfolio of investment-grade fixed income securities, generally with a dollar-weighted average portfolio duration of 1 year or less.

The Fund's investment strategy may involve the frequent trading of portfolio securities. Additionally, the Fund's strategy of investing in derivative instruments and instruments with a maturity of one year or less at the time of acquisition, will also contribute to frequent portfolio trading and high portfolio turnover (typically greater than 300% per year).

The following disclosure for Fixed Income Instruments Risk, Short Positions Risk and Unrated Securities Risk is added to the Fund's Appendix C - Underlying Funds - Principal Risks:

Fixed Income Instruments Risk. The Fund is subject to the general risks and considerations associated with investing in debt securities, including the risk that issuers will fail to make timely payments of principal or interest or default altogether. Lower-rated securities in which the Fund may invest may be more volatile and may decline more in price in response to negative issuer developments or general economic news than higher rated securities. In addition, as interest rates rise, the Fund's investments typically will lose value.

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. Short positions also involve transaction and other costs that will reduce potential Fund gains and increase potential Fund losses.

Unrated Securities Risk. The Fund may purchase unrated securities which are not rated by a rating agency. Unrated securities may be less liquid than comparable rated securities and involve the risk that the Investment Manager may not accurately evaluate the security's comparative credit rating. Analysis of creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality debt securities. To the extent that the Fund purchases unrated securities, the Fund's success in achieving its investment objective may depend more heavily on the Investment Manager's creditworthiness analysis than if the Fund invested exclusively in rated securities.

The rest of the section remains the same.

Shareholders should retain this Supplement for future reference.