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2016-01-01 2025-12-31 iso4217:USD pure 0000773757 false 485BPOS 2025-12-31 0.0721 -0.0001 0.0499 0.0507 -0.0748 0.2804 -0.0370 0.4174 -0.2533 0.1566 Best and Worst Quarterly Returns During the Period Shown in the Bar Chart Best 4th Quarter 2021 17.24% Worst 1st Quarter 2020 -22.29% N-1A COLUMBIA FUNDS SERIES TRUST I 2026-05-01 Summary of the Fund Investment Objective <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">Columbia Real Estate Equity Fund (the Fund) </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">seeks capital appreciation and above-average income by investing, </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">under normal market conditions, at least 80% of its net assets (plus any borrowings for investment purposes) in the </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">stocks of companies principally engaged in the real estate industry, including real estate investment trusts (REITs).</span></div> Fees and Expenses of the Fund <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. <b>You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.</b> You may qualify for sales charge discounts if you and members of your immediate family invest, or agree to invest in the future, at least $50,000 in certain classes of shares of eligible funds distributed by Columbia Management Investment Distributors, Inc. (the Distributor). More information is available about these and other sales charge discounts and waivers from your financial intermediary, and can be found in the <i>Choosing a Share Class</i> section beginning on page 23 of the Fund’s prospectus, in <i>Appendix A</i> to the prospectus beginning on page A-1 and in Appendix S to the Statement of Additional Information (SAI) under <i>Sales Charge Waivers</i> beginning on page S-1.</span><span style="color: #003c78; font-family: arial; font-size: 1pt; line-height: 1pt;"> </span></div> You may qualify for sales charge discounts if you and members of your immediate family invest, or agree to invest in the future, at least $50,000 in certain classes of shares of eligible funds distributed by Columbia Management Investment Distributors, Inc. (the Distributor). More information is available about these and other sales charge discounts and waivers from your financial intermediary, and can be found in the Choosing a Share Class section beginning on page 23 of the Fund’s prospectus, in Appendix A to the prospectus beginning on page A-1 and in Appendix S to the Statement of Additional Information (SAI) under Sales Charge Waivers beginning on page S-1. 50000 Shareholder Fees (fees paid directly from your investment) 0.0575 0 0 0 0 0.0100 0 0 0 0 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0075 0.0075 0.0075 0.0075 0.0075 0.0025 0.0000 0.0000 0.0000 0.0000 0.0030 0.0030 0.0020 0.0015 0.0030 0.0130 0.0105 0.0095 0.0090 0.0105 -0.0011 -0.0011 -0.0010 -0.0011 -0.0011 0.0119 0.0094 0.0085 0.0079 0.0094 This charge is imposed on certain investments of between $1 million and $50 million redeemed within 18 months after purchase, as follows: 1.00% if redeemed within 12 months after purchase, and 0.50% if redeemed more than 12, but less than 18, months after purchase, with certain limited exceptions. “Total annual Fund operating expenses” include acquired fund fees and expenses (expenses the Fund incurs indirectly through its investments in other investment companies) and may be higher than the ratio of expenses to average net assets shown in the Financial Highlights section of this prospectus because the ratio of expenses to average net assets does not include acquired fund fees and expenses. April 30, 2027  Example <div style="margin-top: 6pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">The following example is intended to help you compare the cost of investing in the Fund with the cost of investing </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">in other mutual funds. The example illustrates the hypothetical expenses that you would incur over the time periods </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">indicated, and assumes that:</span><span style="color: #003c78; font-family: arial; font-size: 10pt; line-height: 12pt;"> </span></div> <div> <div style="clear: both; margin-top: 4.00pt; position: relative; width: 100%;"> <div style="float: left; line-height: 10pt; margin-left: 6pt; text-align: left; width: 4.45pt;"><span style="color: #003c78; font-family: arial; font-size: 8pt; position: relative; top: -0.5pt;">■</span></div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">you invest $10,000 in the applicable class of Fund shares for the periods indicated,</span><span style="color: #003c78; font-family: arial; font-size: 10pt; line-height: 12pt;"> </span></div> </div> <div style="clear: both; position: relative;"> </div> </div> <div> <div style="clear: both; margin-top: 4.00pt; position: relative; width: 100%;"> <div style="float: left; line-height: 10pt; margin-left: 6pt; text-align: left; width: 4.45pt;"><span style="color: #003c78; font-family: arial; font-size: 8pt; position: relative; top: -0.5pt;">■</span></div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">your investment has a 5% return each year, and</span><span style="color: #003c78; font-family: arial; font-size: 10pt; line-height: 12pt;"> </span></div> </div> <div style="clear: both; position: relative;"> </div> </div> <div> <div style="clear: both; margin-top: 4.00pt; position: relative; width: 100%;"> <div style="float: left; line-height: 10pt; margin-left: 6pt; text-align: left; width: 4.45pt;"><span style="color: #003c78; font-family: arial; font-size: 8pt; position: relative; top: -0.5pt;">■</span></div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">the Fund’s total annual operating expenses remain the same as shown in the </span><span style="color: #003c78; font-family: arial; font-size: 10pt; font-style: italic;">Annual Fund Operating Expenses</span><span style="color: #003c78; font-family: arial; font-size: 10pt; line-height: 12pt;"> </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">table above.</span></div> </div> <div style="clear: both; position: relative;"> </div> </div> <div style="margin-top: 6pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">Since the waivers and/or reimbursements shown in the</span><span style="color: #003c78; font-family: arial; font-size: 10pt; font-style: italic;"> Annual Fund Operating Expenses</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> table above expire as </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">indicated in the preceding table, they are only reflected in the 1 year example and the first year of the other </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">examples. Although your actual costs may be higher or lower, based on the assumptions listed above, your costs </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">would be:</span><span style="color: #003c78; font-family: arial; font-size: 1pt; line-height: 1pt;"> </span></div> 689 689 953 953 1237 1237 2044 2044 96 96 323 323 569 569 1273 1273 87 87 293 293 516 516 1157 1157 81 81 276 276 488 488 1098 1098 96 96 323 323 569 569 1273 1273 Portfolio Turnover <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">The Fund may pay transaction costs, such as commissions, when it buys and sells securities (or “turns over” its </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">was </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">43</span><span style="color: #003c78; font-family: arial; font-size: 10pt;">% of the average value of its portfolio.</span></div> 0.43 Principal Investment Strategies <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">Under normal circumstances, the Fund invests at least 80% of its net assets (</span><span style="color: #003c78; font-family: arial; font-size: 10pt;">plus</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> the amount of any borrowings for </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">investment purposes) in equity securities of companies principally engaged in the real estate industry (Real Estate </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Companies), including real estate investment trusts (REITs). A company is considered to be “principally engaged” in </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">the real estate industry if at least 50% of its gross income or net profits are attributable to the ownership, </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">construction, management or sale of residential, commercial or industrial real estate. The Fund will concentrate its investments in the real estate industry. The Fund takes long and short positions in equity REITs, mortgage REITs and hybrid REITs.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">The Fund’s investment strategy may involve the frequent trading of portfolio securities.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">The Fund is non-diversified, which means that it can invest a greater percentage of its assets in the securities of </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">fewer issuers than can a diversified fund.</span><span style="color: #003c78; font-family: arial; font-size: 10pt; line-height: 12pt;"> </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">The Fund anticipates that its number of holdings will increase and, as a </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">result, the Fund may operate as a diversified fund. In addition to making direct investments in Real Estate </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Companies, the Fund will invest in derivatives, particularly contracts for differences (CFDs), which are a type of swap </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">arrangement, to obtain long and short exposures to Real Estate Companies. Columbia Management Investment </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Advisers, LLC (the Investment Manager) uses CFDs to express its view of relative value between Real Estate </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Companies operating in the same part of the real estate market. Specifically, the Investment Manager uses CFDs to </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">extend the Fund’s long position in holdings of which it has a favorable view and enters into short positions in Real </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Estate Companies of which it has a less favorable view. CFDs create leverage, which may exaggerate increases or </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">decreases in the value of the Fund’s overall portfolio. Through investment in CFDs, the Fund generally expects </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">exposures of approximately 30% (but normally not more than 35%) of the Fund’s net assets in short positions and </span></div> <div style="line-height: 12.0pt; text-align: left;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">approximately 130% (but normally not more than 135%) of the Fund’s net assets in long positions. The Investment </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Manager generally seeks to maintain CFD long and short exposures for the Fund that are approximately balanced. </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">The Fund may include investments in derivatives towards its 80% policy.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">In selecting investments and determining investment exposures, including the Fund’s long and short positions </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">through CFDs, the Investment Manager uses fundamental analysis in identifying investment opportunities and risks, </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">and in constructing the Fund’s portfolio.</span></div> The Fund will concentrate its investments in the real estate industry. The Fund takes long and short positions in equity REITs, mortgage REITs and hybrid REITs. There is no assurance that the Fund will achieve its investment objective and you may lose money. An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Active Management Risk.</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> Due to its active management, the Fund could underperform its benchmark index and/or </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">other funds with similar investment objectives and/or strategies.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Changing Distribution Level Risk.</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> The Fund normally expects to receive income which may include interest, </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">dividends and/or capital gains, depending upon its investments. The distribution amounts paid by the Fund will vary </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">and generally depend on the amount of income the Fund earns (less expenses) on its portfolio holdings, and capital </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">gains or losses it recognizes. A decline in the Fund’s income or net capital gains arising from its investments may </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">reduce its distribution level.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Counterparty Risk.</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> Counterparty risk is the risk that a counterparty to a transaction in a financial instrument held by </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">the Fund or by a special purpose or structured vehicle invested in by the Fund may become insolvent or otherwise </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">fail to perform its obligations. As a result, the Fund may obtain no or limited recovery of its investment, and any </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">recovery may be significantly delayed.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Derivatives Risk. </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Derivatives may involve significant risks. Derivatives are financial instruments with a value in </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">relation to, or derived from, the value of an underlying asset(s) or other reference, such as an index, rate or other </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">economic indicator (each an underlying reference). Derivatives may include those that are privately placed or </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">otherwise exempt from SEC registration, including certain Rule 144A eligible securities. Derivatives could result in </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Fund losses if the underlying reference does not perform as anticipated. Use of derivatives is a highly specialized </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">activity that can involve investment techniques, risks, and tax planning different from those associated with more </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">traditional investment instruments. The Fund’s derivatives strategy may not be successful</span><span style="color: #003c78; font-family: arial; font-size: 10pt;">,</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> and use of certain </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">derivatives could result in substantial, potentially unlimited, losses to the Fund regardless of the Fund’s actual </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">investment. A relatively small movement in the price, rate or other economic indicator associated with the underlying </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">reference may result in substantial losses for the Fund. Derivatives may be more volatile than other types of </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">investments. The value of derivatives may be influenced by a variety of factors, including national and international </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">political and economic developments. Potential changes to the regulation of the derivatives markets may make </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">derivatives more costly, may limit the market for derivatives, or may otherwise adversely affect the value or </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">performance of derivatives. Derivatives can increase the Fund’s risk exposure to underlying references and their </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while potentially exposing </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">the Fund to correlation risk, counterparty risk, hedging risk, inflation risk, leverage risk, liquidity risk, pricing risk and </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">volatility risk.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Derivatives Risk – Swaps Risk. </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">In a typical swap transaction, two parties agree to exchange the return earned on a </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">specified underlying reference for a fixed return or the return from another underlying reference during a specified </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">period of time. Swaps may be difficult to value and may be illiquid. Swaps could result in Fund losses if the </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">underlying asset or reference does not perform as anticipated. Swaps create significant investment leverage such </span></div> <div style="line-height: 12.0pt; text-align: left;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">that a relatively small price movement in a swap may result in immediate and substantial losses to the Fund. The </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Fund may only close out a swap with its particular counterparty</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> and may only transfer a position with the consent of </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">that counterparty. Certain swaps, such as short swap transactions and total return swaps, have the potential for </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">unlimited losses, regardless of the size of the initial position. Swaps can increase the Fund’s risk exposure to </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">risk, while potentially exposing the Fund to correlation risk, counterparty risk, hedging risk, inflation risk, leverage risk, </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">liquidity risk, pricing risk and volatility risk.</span></div> <div> <div style="clear: both; margin-top: 4pt; position: relative; width: 100%;"> <div style="float: left; line-height: 10pt; text-align: left; width: 4.45pt;"><span style="color: #003c78; font-family: arial; font-size: 8pt; position: relative; top: -0.5pt;">■</span></div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 500.00pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Contracts for differences (CFDs) </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">are swap arrangements in which the parties agree that their return (or loss) will </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">be based on the relative performance of two or more individual securities, different groups or baskets of securities </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">or other instruments where the parties agree to exchange the difference in the settlement price between the open </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">and closing trades on a particular asset(s). CFDs enable investors to speculate on whether a market will go up or </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">down, and profit from the price movement without owning the underlying asset(s). CFDs essentially allow </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">investors to trade the direction of securities, including over the very short term. CFDs are subject to the risks </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">described above under Derivatives Risk – Swaps Risk.</span></div> </div> <div style="clear: both; position: relative;"> </div> </div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Equity Securities Risk.</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> Equity securities may experience significant volatility. Such securities may fall sharply in </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">response to adverse events affecting overall markets, a particular industry or sector, or an individual company’s </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">financial condition.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Industry Concentration Risk.</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> Investments that are concentrated in a particular industry will make the Fund’s portfolio </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">value more susceptible to the events or conditions impacting that particular industry.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Issuer Risk.</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> An issuer in which the Fund invests or to which it has exposure may perform poorly or below </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">expectations, and the value of its securities may therefore decline, which may negatively affect the Fund’s </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">performance. Underperformance of an issuer may be caused by poor management decisions, competitive pressures, </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">breakthroughs in technology, reliance on suppliers, labor problems or shortages, corporate restructurings, fraudulent </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">disclosures, natural disasters, military confrontations and actions, war, other conflicts, terrorism, disease/virus </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">outbreaks, epidemics or other events, conditions and factors which may impair the value of your investment in the </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Fund.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Leverage Risk.</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> Leverage occurs when the Fund increases its assets available for investment by taking short </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">positions </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">or</span><span style="color: #003c78; font-family: arial; font-size: 10pt; line-height: 12pt;"> </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">using</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> borrowings, derivatives, or similar instruments or techniques. Use of leverage can produce </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">volatility and may exaggerate changes in the NAV of Fund shares and in the return on the Fund’s portfolio, which may </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">increase the risk that the Fund will lose more than it has invested. If the Fund uses leverage, through the purchase of </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">particular instruments such as derivatives, the Fund may experience capital losses that exceed the net assets of the </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Fund. Leverage presents the opportunity for increased net income and capital gains, but may also exaggerate the </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Fund’s volatility and risk of loss. There can be no guarantee that a leveraging strategy will be successful.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Market Risk.</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> The Fund may incur losses due to declines in the value of one or more securities in which it invests. </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">These declines may be due to factors affecting a particular issuer, or the result of, among other things, political, </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">regulatory, market, economic or social developments affecting the relevant market(s) more generally. In addition, </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">turbulence in financial markets and reduced liquidity in equity, credit and/or fixed income markets may negatively </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">affect many issuers, which could adversely affect the Fund’s ability to price or value hard-to-value assets in thinly </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">traded and closed markets and could cause significant redemptions and operational challenges. Global economies </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">and financial markets are increasingly interconnected, and conditions and events in one country, region or financial </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">market may adversely impact issuers in a different country, region or financial market. These risks may be magnified </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">if certain events or developments adversely interrupt the global supply chain; in these and other circumstances, such </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">risks might affect companies worldwide. As a result, local, regional or global events such as terrorism, war, other </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">conflicts, natural disasters, disease/virus outbreaks and epidemics or other public health issues, recessions, </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">depressions or other events – or the potential for such events – could have a significant negative impact on global </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">economic and market conditions.</span></div> <div style="line-height: 12.0pt; text-align: left;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Non-Diversified Fund Risk.</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> The Fund is non-diversified, which generally means that it may invest a greater </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">percentage of its total assets in the securities of fewer issuers than a “diversified” fund. This increases the risk that a </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">change in the value of any one investment held by the Fund could affect the overall value of the Fund more than it </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">would affect that of a diversified fund holding a greater number of investments. Accordingly, the Fund's value will </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">likely be more volatile than the value of a more diversified fund.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Portfolio Turnover, Frequent Trading and Tax Risk.</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> The Fund may actively and frequently trade investments in the </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Fund’s portfolio to carry out its investment strategies. Use of swaps, including contracts for differences, and other </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">derivatives increases the possibility that the Fund, as relevant, will generate taxable ordinary income. The Fund </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">cannot carry back or carry forward any net operating losses (defined as ordinary deductions in excess of ordinary </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">income for the year) and cannot use capital loss carryforwards to offset ordinary income. Frequent trading of other </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">investments, such as REITs, increases the possibility that the Fund will generate capital gains. Both short-term </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">capital gains and net ordinary gains are distributed as ordinary income and are generally taxable to shareholders at </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">higher rates than long-term capital gains for U.S. federal income tax purposes, which could reduce the Fund’s after-tax</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> return for shareholders owning Fund shares in taxable accounts. These trading strategies can mean higher </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">brokerage and other transaction costs. The costs and tax effects associated with such trading strategies may </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">adversely affect the Fund’s after-tax performance. In July 2023, the Fund changed its Principal Investment Strategies, </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">which has resulted in increased portfolio turnover relative to the Fund’s strategy in place prior to July 2023.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Real Estate-Related Investment Risk.</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> Investments in real estate investment trusts (REITs) and in securities of other </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">companies (wherever organized) principally engaged in the real estate industry subject the Fund to, among other </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">things, risks similar to those of direct investments in real estate and the real estate industry in general. These include </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">risks related to general and local economic conditions, possible lack of availability of financing and changes in </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">interest rates or property values. The value of interests in a REIT may be affected by, among other factors, changes in </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">the value of the underlying properties owned by the REIT, changes in the prospect for earnings and/or cash flow </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">growth of the REIT itself, defaults by borrowers or tenants, market saturation, decreases in market rates for rents, </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">and other economic, political, or regulatory matters affecting the real estate industry, including REITs. REITs may be </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">subject to more abrupt or erratic price movements than the overall securities markets. In a rising interest rate </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">environment, the stock prices of real estate-related investments may decline and the borrowing costs of these </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">companies may increase. REITs are also subject to the risk of failing to qualify for favorable tax treatment under the </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Internal Revenue Code of 1986, as amended. The failure of a REIT to continue to qualify as a REIT for tax purposes </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">can materially and adversely affect its value. Some REITs (especially mortgage REITs) are affected by risks similar to </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">those associated with investments in debt securities including changes in interest rates and the quality of credit </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">extended. Because the value of REITs and other real estate-related companies may fluctuate widely in response to </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">changes in factors affecting the real estate markets, the value of an investment in the Fund may be more volatile </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">than the value of an investment in a fund that is invested in a more diverse range of market sectors.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">Short Positions Risk.</span><span style="color: #003c78; font-family: arial; font-size: 10pt;"> The Fund may establish short positions which introduce more risk to the Fund than long </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">positions (where the Fund owns the instrument or other asset) because the maximum sustainable loss on an </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">instrument or other asset purchased (held long) is limited to the amount paid for the instrument or other asset plus </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">the transaction costs, whereas there is no maximum price of the shorted instrument or other asset when purchased </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">in the open market. Therefore, in theory, short positions have unlimited risk. The Fund’s use of short positions in </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">effect “leverages” the Fund. Leverage potentially exposes the Fund to greater risks of loss due to unanticipated </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">market movements, which may magnify losses and increase the volatility of returns. To the extent the Fund takes a </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">short position in a derivative instrument or other asset, this involves the risk of a potentially unlimited increase in the </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">value of the underlying instrument or other asset.</span></div> Performance Information <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">The following bar chart and table show you how the Fund has performed in the past, and can help you understand the risks of investing in the Fund. The bar chart shows how the Fund’s Class  A  share performance (without sales charges) has varied for each full calendar year shown. If the sales charges were reflected, returns shown would be lower. The table below the bar chart compares the Fund’s returns (after applicable sales charges shown in the <i>Shareholder Fees</i> table in this prospectus) for the periods shown with a broad measure of market performance, as well as another measure of performance for markets in which the Fund may invest.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">The performance of one or more share classes shown in the table below begins before the indicated inception date </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">for such share class. The returns shown for each such share class include the returns of the Fund’s Class Inst  </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">shares for periods prior to its inception date.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">Except for differences in annual returns resulting from differences in expenses and sales charges (where applicable), </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">the share classes of the Fund would have substantially similar annual returns because all share classes of the Fund </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">invest in the same portfolio of securities.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">The after-tax returns shown in the <i>Average Annual Total Returns</i> table below are calculated using the highest historical individual U.S. federal marginal income tax rates in effect during the period indicated in the table and do not reflect the impact of state, local or foreign taxes. Your actual after-tax returns will depend on your personal tax situation and may differ from those shown in the table. In addition, the after-tax returns shown in the table do not apply to shares held in tax-advantaged accounts such as 401(k) plans or Individual Retirement Accounts (IRAs). The after-tax returns are shown only for Class A  shares and will vary for other share classes. Returns after taxes on distributions and sale of Fund shares are higher than before-tax returns for certain periods shown because they reflect the tax benefit of capital losses realized on the redemption of Fund shares.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt;">The Fund’s performance prior to July 3, 2023, reflects returns achieved pursuant to different principal investment </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">strategies. If the Fund’s current strategies had been in place for the prior periods, results shown may have been </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">different.</span></div> <div style="margin-top: 4pt;"><span style="color: #003c78; font-family: arial; font-size: 10pt; font-weight: bold;">The Fund’s past performance (before and after taxes) is no guarantee of how the Fund will perform in the future.</span><span style="color: #003c78; font-family: arial; font-size: 10pt; line-height: 12pt;"> </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">Updated performance information can be obtained by calling toll-free 800.345.6611 or visiting </span><span style="color: #003c78; font-family: arial; font-size: 10pt;">columbiathreadneedleus.com.</span><span style="color: #003c78; font-family: arial; font-size: 1pt; line-height: 1pt;"> </span></div> The following bar chart and table show you how the Fund has performed in the past, and can help you understand the risks of investing in the Fund. The bar chart shows how the Fund’s Class  A  share performance (without sales charges) has varied for each full calendar year shown. If the sales charges were reflected, returns shown would be lower. The table below the bar chart compares the Fund’s returns (after applicable sales charges shown in the Shareholder Fees table in this prospectus) for the periods shown with a broad measure of market performance, as well as another measure of performance for markets in which the Fund may invest. The bar chart shows how the Fund’s Class  A  share performance (without sales charges) has varied for each full calendar year shown. If the sales charges were reflected, returns shown would be lower. The table below the bar chart compares the Fund’s returns (after applicable sales charges shown in the Shareholder Fees table in this prospectus) for the periods shown with a broad measure of market performance, as well as another measure of performance for markets in which the Fund may invest. The after-tax returns shown in the Average Annual Total Returns table below are calculated using the highest historical individual U.S. federal marginal income tax rates in effect during the period indicated in the table and do not reflect the impact of state, local or foreign taxes. In addition, the after-tax returns shown in the table do not apply to shares held in tax-advantaged accounts such as 401(k) plans or Individual Retirement Accounts (IRAs). The after-tax returns are shown only for Class A  shares and will vary for other share classes. Returns after taxes on distributions and sale of Fund shares are higher than before-tax returns for certain periods shown because they reflect the tax benefit of capital losses realized on the redemption of Fund shares. The Fund’s past performance (before and after taxes) is no guarantee of how the Fund will perform in the future. 800.345.6611 columbiathreadneedleus.com Year by Year Total Return (%)as of December 31 Each Year Best 2021-12-31 0.1724 Worst 2020-03-31 -0.2229  Average Annual Total Returns After Applicable Sales Charges (for periods ended December 31, 2025)   2002-11-01 2002-11-01 2002-11-01 -0.0577 0.0434 0.0453 -0.0709 0.0155 0.0191 -0.0253 0.0305 0.0305 1994-04-01 0.0024 0.0585 0.0540 2011-03-07 0.0023 0.0593 0.0552 2017-03-01 0.0028 0.0600 0.0556 2024-10-02 0.0014 0.0585 0.0540 0.0288 0.0663 0.0570 0.1715 0.1315 0.1429 “Total annual Fund operating expenses” include acquired fund fees and expenses (expenses the Fund incurs indirectly through its investments in other investment companies) and may be higher than the ratio of expenses to average net assets shown in the Financial Highlights section of this prospectus because the ratio of expenses to average net assets does not include acquired fund fees and expenses. Columbia Management Investment Advisers, LLC and certain of its affiliates have contractually agreed to waive fees and/or to reimburse expenses (excluding transaction costs and certain other investment related expenses, interest, taxes, acquired fund fees and expenses, and infrequent and/or unusual expenses) through April 30, 2027, unless sooner terminated at the sole discretion of the Fund’s Board of Trustees. Under this agreement, the Fund’s net operating expenses, subject to applicable exclusions, will not exceed the annual rates of 1.19% for Class A, 0.94% for Class Inst, 0.85% for Class Inst2, 0.79% for Class Inst3 and 0.94% for Class S. Any differences in these annual rates relative to the annual rates noted in the last row of the above table (e.g., net expense ratios) are due to applicable exclusions under the agreement. This charge is imposed on certain investments of between $1 million and $50 million redeemed within 18 months after purchase, as follows: 1.00% if redeemed within 12 months after purchase, and 0.50% if redeemed more than 12, but less than 18, months after purchase, with certain limited exceptions.