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0.3355 0.3794 0.1977 -0.2917 0.4175 Best and Worst Quarterly Returns During the Period Shown in the Bar Chart Best 2nd Quarter 2020 27.17% Worst 2nd Quarter 2022 -21.12% 0.3891 -0.3215 0.1569 0.1066 -0.0874 0.3513 -0.0535 0.3749 0.4744 0.0890 Year by Year Total Return (%)as of December 31 Each Year* Best and Worst Quarterly Returns During the Period Shown in the Bar Chart Best 2nd Quarter 2020 31.89% Worst 2nd Quarter 2022 -23.57% N-1A COLUMBIA FUNDS SERIES TRUST I 2026-08-01 Summary of the Fund Investment Objective <div style="margin-top: 4pt;">Columbia Integrated Large Cap Growth Fund II (the Fund) seeks long-term capital appreciation.</div> Fees and Expenses of the Fund <div style="margin-top: 4pt;">This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below. </div> Shareholder Fees (fees paid directly from your investment) 0 0 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0077 0.0000 0.0041 0.0118 -0.0046 0.0072 Management fees have been restated to reflect current fees based on current asset levels. Other expenses have been restated and are based on estimated amounts for the Fund’s current fiscal year, taking into consideration changes in the Fund’s net assets. “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. July 31, 2027 Example <div style="margin-top: 6pt;">The following example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example illustrates the hypothetical expenses that you would incur over the time periods indicated, and assumes that: </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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;">you invest $10,000 in the class of Fund shares for the periods indicated, </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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;">you redeem all your shares at the end of the period, </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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;">your investment has a 5% return each year, and </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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;">the Fund’s total annual operating expenses remain the same as shown in the Annual Fund Operating Expenses table above.</div> </div> <div style="clear: both; position: relative;"> </div> </div> <div style="line-height: 12.0pt; margin-left: 6pt; text-align: left;">Since the waivers and/or reimbursements shown in the Annual Fund Operating Expenses table above expire as indicated in the preceding table, they are only reflected in the 1 year example and the first year of the other examples. Although your actual costs may be higher or lower, based on the assumptions listed above, your costs would be: </div> 74 74 329 329 605 605 1391 1391 Portfolio Turnover <div style="margin-top: 4pt;">The Fund may pay transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 86% of the average value of its portfolio.</div> 0.86 Principal Investment Strategies <div style="margin-top: 4pt;">Under normal circumstances, the Fund invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of large capitalization companies. These companies have market capitalizations in the range of companies in the Russell 1000® Growth Index (the Capitalization Index), which ranged between $776.8 million and $4.8 trillion as of June 30, 2026. The market capitalization range and composition of companies in the Capitalization Index are subject to change. As such, the size of the companies in which the Fund invests may change. The Fund may continue to hold a security even if the company’s market capitalization is no longer within the range of the Capitalization Index. Under normal circumstances, the Fund also invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of “growth” companies. The Fund considers “growth” companies to be those companies that are either constituents of an index constructed by a third party to identify companies with various characteristics of growth companies, have a higher Institutional Brokers' Estimate System (I/B/E/S) medium-term growth forecast (two year) than the median ranked stock within the company’s Global Industry Classification Standard (GICS) sector, or have a higher sales per share historical growth rate (five year) than the median ranked stock within the company’s GICS sector. The third-party broad-based index currently used to identify growth companies is the Russell 3000® Growth Index, although the Fund may change this index without prior notice. The I/B/E/S is a database used by brokers and investors to access the estimates made by stock analysts regarding the future earnings of publicly traded American companies. The I/B/E/S medium-term growth forecast is a measure of the average annualized EPS (earnings per share) growth forecast of contributing analysts/estimators for the forthcoming two years.</div> <div style="margin-top: 4pt;">The Fund invests substantially in securities of U.S. issuers. The Fund generally invests in common stocks. The Fund may at times emphasize one or more sectors in selecting its investments. As of its most recent fiscal year end, the Fund had an investment emphasis in the information technology sector.</div> <div style="margin-top: 4pt;">The Fund may also invest in exchange-traded funds (ETFs).</div> <div style="margin-top: 4pt;">Under normal circumstances, the Fund invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of large capitalization companies. These companies have market capitalizations in the range of companies in the Russell 1000® Growth Index (the Capitalization Index), which ranged between $776.8 million and $4.8 trillion as of June 30, 2026. The market capitalization range and composition of companies in the Capitalization Index are subject to change. As such, the size of the companies in which the Fund invests may change. The Fund may continue to hold a security even if the company’s market capitalization is no longer within the range of the Capitalization Index. Under normal circumstances, the Fund also invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of “growth” companies. The Fund considers “growth” companies to be those companies that are either constituents of an index constructed by a third party to identify companies with various characteristics of growth companies, have a higher Institutional Brokers' Estimate System (I/B/E/S) medium-term growth forecast (two year) than the median ranked stock within the company’s Global Industry Classification Standard (GICS) sector, or have a higher sales per share historical growth rate (five year) than the median ranked stock within the company’s GICS sector. The third-party broad-based index currently used to identify growth companies is the Russell 3000® Growth Index, although the Fund may change this index without prior notice. The I/B/E/S is a database used by brokers and investors to access the estimates made by stock analysts regarding the future earnings of publicly traded American companies. The I/B/E/S medium-term growth forecast is a measure of the average annualized EPS (earnings per share) growth forecast of contributing analysts/estimators for the forthcoming two years.</div> Under normal circumstances, the Fund invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of large capitalization companies.Under normal circumstances, the Fund also invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of “growth” companies. These companies have market capitalizations in the range of companies in the Russell 1000® Growth Index (the Capitalization Index), which ranged between $776.8 million and $4.8 trillion as of June 30, 2026.The market capitalization range and composition of companies in the Capitalization Index are subject to change.As such, the size of the companies in which the Fund invests may change. The Fund may continue to hold a security even if the company’s market capitalization is no longer within the range of the Capitalization Index. The Fund considers “growth” companies to be those companies that are either constituents of an index constructed by a third party to identify companies with various characteristics of growth companies, have a higher Institutional Brokers' Estimate System (I/B/E/S) medium-term growth forecast (two year) than the median ranked stock within the company’s Global Industry Classification Standard (GICS) sector, or have a higher sales per share historical growth rate (five year) than the median ranked stock within the company’s GICS sector. The third-party broad-based index currently used to identify growth companies is the Russell 3000® Growth Index, although the Fund may change this index without prior notice. The I/B/E/S is a database used by brokers and investors to access the estimates made by stock analysts regarding the future earnings of publicly traded American companies. The I/B/E/S medium-term growth forecast is a measure of the average annualized EPS (earnings per share) growth forecast of contributing analysts/estimators for the forthcoming two years. 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;">Active Management Risk. Due to its active management, the Fund could underperform its benchmark index and/or other funds with similar investment objectives and/or strategies.</div> <div style="line-height: 12.0pt; text-align: left;">Equity Securities Risk. Equity securities may experience significant volatility. Such securities may fall sharply in response to adverse events affecting overall markets, a particular industry or sector, or an individual company’s financial condition.</div> <div style="margin-top: 4pt;">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.</div> <div style="margin-top: 4pt;">Growth Securities Risk. Growth securities typically trade at a higher multiple of earnings than other types of equity securities. Accordingly, the market values of growth securities may never reach their expected market values and may decline in price. In addition, growth securities, at times, may not perform as well as value securities or the stock market in general, and may be out of favor with investors for varying periods of time. Growth securities may also be sensitive to movements in interest rates.</div> <div style="margin-top: 4pt;">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. Due to the expenses and costs of an underlying fund being 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. The Investment Manager has a conflict of interest in selecting affiliated underlying funds over unaffiliated underlying funds because it receives management fees from affiliated underlying funds, and it has a conflict in selecting among affiliated underlying funds, because the fees paid to it by certain affiliated underlying funds are higher than the fees paid by other affiliated 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 is not identified in a timely manner or at all. The underlying funds may not achieve their investment objective. The Fund, through its investment in underlying funds, may not achieve its investment objective.</div> <div style="margin-top: 4pt;">Issuer Risk. An issuer in which the Fund invests or to which it has exposure may perform poorly or below expectations, and the value of its securities may therefore decline, which may negatively affect the Fund’s performance. Underperformance of an issuer may be caused by poor management decisions, competitive pressures, breakthroughs in technology, reliance on suppliers, labor problems or shortages, corporate restructurings, fraudulent disclosures, natural disasters, military confrontations and actions, war, other conflicts, terrorism, disease/virus outbreaks, epidemics or other events, conditions and factors which may impair the value of your investment in the Fund.</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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 500.00pt;">Large-Cap Stock Risk. Investments in larger, more established companies (larger companies) may involve certain risks associated with their larger size. For instance, larger companies may be less able to respond quickly to new competitive challenges, such as changes in consumer tastes or innovation from smaller competitors. Also, larger companies are sometimes less able to achieve as high growth rates as successful smaller companies, especially during extended periods of economic expansion.</div> </div> <div style="clear: both; position: relative;"> </div> </div> <div style="line-height: 12.0pt; text-align: left;">Market Risk. The Fund may incur losses due to declines in the value of one or more securities in which it invests. These declines may be due to factors affecting a particular issuer, or the result of, among other things, political, regulatory, market, economic or social developments affecting the relevant market(s) more generally. In addition, turbulence in financial markets and reduced liquidity in equity, credit and/or fixed income markets may negatively affect many issuers, which could adversely affect the Fund’s ability to price or value hard-to-value assets in thinly traded and closed markets and could cause significant redemptions and operational challenges. Global economies and financial markets are increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. These risks may be magnified if certain events or developments adversely interrupt the global supply chain; in these and other circumstances, such risks might affect companies worldwide. As a result, local, regional or global events such as terrorism, war, other conflicts, natural disasters, disease/virus outbreaks and epidemics or other public health issues, recessions, depressions or other events – or the potential for such events – could have a significant negative impact on global economic and market conditions.</div> <div style="margin-top: 4pt;">Sector Risk. At times, the Fund may have a significant portion of its assets invested in securities of companies conducting business in a related group of industries within one or more economic sectors, including the information technology sector. Companies in the same sector may be similarly affected by economic, regulatory, political or market events or conditions, which may make the Fund vulnerable to unfavorable developments in that group of industries or economic sector.</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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 500.00pt;">Information Technology Sector. The Fund is vulnerable to the particular risks that may affect companies in the information technology sector. Companies in the information technology sector are subject to certain risks, including the risk that new services, equipment or technologies will not be accepted by consumers and businesses or will become rapidly obsolete. Performance of such companies may be affected by factors including obtaining and protecting patents (or the failure to do so) and significant competitive pressures, including aggressive pricing of their products or services, new market entrants, competition for market share and short product cycles due to an accelerated rate of technological developments. Such competitive pressures may lead to limited earnings and/or falling profit margins. As a result, the value of their securities may fall or fail to rise. In addition, many information technology sector companies have limited operating histories and prices of these companies’ securities historically have been more volatile than other securities, especially over the short term. Some companies in the information technology sector are facing increased government and regulatory scrutiny and may be subject to adverse government or regulatory action, which could negatively impact the value of their securities.</div> </div> <div style="clear: both; position: relative;"> </div> </div> Performance Information <div style="margin-top: 4pt;">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 Inst share performance has varied for each full calendar year shown. The table below the bar chart compares the Fund’s returns 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.</div> <div style="margin-top: 4pt;">The performance of Class Inst shares shown in the table below begins before its inception date. The returns shown for Class Inst shares include the returns of the Fund’s Class A shares through January 2, 2017. Additionally, the returns shown in the bar chart include the performance of the Fund’s Class A shares through January 2, 2017 (performance of Class Inst shares is shown for all other periods since the Fund no longer offers Class A shares). Class A shares were offered prior to the inception date of the Fund’s Class Inst shares but have since been merged into the Fund’s Class Inst shares. 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. 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). </div> <div style="line-height: 12.0pt; text-align: left;">The Fund’s performance prior to December 2025 reflects returns achieved by one or more different subadvisers that managed the Fund according to different principal investment strategies. If the Fund’s current portfolio managers and strategies had been in place for the prior periods, results shown may have been different.</div> <div style="margin-top: 4pt;">The Fund’s past performance (before and after taxes) is no guarantee of how the Fund will perform in the future. Updated performance information can be obtained by calling toll-free 800.345.6611 or visiting columbiathreadneedleus.com. </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 Inst share performance has varied for each full calendar year shown. The table below the bar chart compares the Fund’s returns 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 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 2020-06-30 0.2717 Worst 2022-06-30 -0.2112 Year to Date return 2026-06-30 0.0704 Average Annual Total Returns (for periods ended December 31, 2025) 2017-01-03 2017-01-03 2017-01-03 0.1509 0.1325 0.1552 0.1190 0.1038 0.1289 0.1050 0.0977 0.1206 0.1856 0.1532 0.1813 0.1737 0.1359 0.1459 Summary of the Fund Investment Objective <div style="margin-top: 4pt;">Columbia Select Large Cap Growth Fund (the Fund) seeks long-term capital appreciation.</div> Fees and Expenses of the Fund <div style="margin-top: 4pt;">This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. 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. 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 21 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. </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 21 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 0.0100 0 0 0 0 0 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0077 0.0077 0.0077 0.0077 0.0077 0.0077 0.0025 0.0000 0.0000 0.0000 0.0050 0.0000 0.0015 0.0015 0.0010 0.0005 0.0015 0.0015 0.0117 0.0092 0.0087 0.0082 0.0142 0.0092 -0.0016 -0.0016 -0.0017 -0.0017 -0.0016 -0.0016 0.0101 0.0076 0.0070 0.0065 0.0126 0.0076 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. Management fees have beenrestated to reflect current fees based on current asset levels.Other expenses have been restated to reflect current fees paid by the Fund. “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. July 31, 2027 Example <div style="margin-top: 6pt;">The following example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example illustrates the hypothetical expenses that you would incur over the time periods indicated, and assumes that: </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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;">you invest $10,000 in the applicable class of Fund shares for the periods indicated, </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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;">you redeem all your shares at the end of the period, </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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;">your investment has a 5% return each year, and </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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;">the Fund’s total annual operating expenses remain the same as shown in the Annual Fund Operating Expenses table above.</div> </div> <div style="clear: both; position: relative;"> </div> </div> <div style="margin-top: 6pt;">Since the waivers and/or reimbursements shown in the Annual Fund Operating Expenses table above expire as indicated in the preceding table, they are only reflected in the 1 year example and the first year of the other examples. Although your actual costs may be higher or lower, based on the assumptions listed above, your costs would be: </div> 672 672 910 910 1167 1167 1900 1900 78 78 277 277 494 494 1117 1117 72 72 261 261 466 466 1057 1057 66 66 245 245 438 438 998 998 128 128 434 434 761 761 1688 1688 78 78 277 277 494 494 1117 1117 Portfolio Turnover <div style="margin-top: 4pt;">The Fund may pay transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 39% of the average value of its portfolio.</div> 0.39 Principal Investment Strategies <div style="margin-top: 4pt;">Under normal circumstances, the Fund invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in common stocks of U.S. and foreign companies that have market capitalizations in the range of companies in the Russell 1000® Growth Index (the Capitalization Index). The market capitalization range of the companies included within the Capitalization Index was $776.8 million to $4.8 trillion as of June 30, 2026. The market capitalization range and composition of companies in the Capitalization Index are subject to change. As such, the size of the companies in which the Fund invests may change. The Fund may continue to hold a security even if the company’s market capitalization is no longer within the range of the Capitalization Index. The Fund invests primarily in common stocks of companies believed to have the potential for long-term growth. Under normal circumstances, the Fund also invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of “growth” companies. The Fund considers “growth” companies to be those companies that are either constituents of an index constructed by a third party to identify companies with various characteristics of growth companies, have a higher Institutional Brokers' Estimate System (I/B/E/S) medium-term growth forecast (two year) than the median ranked stock within the company’s Global Industry Classification Standard (GICS) sector, or have a higher sales per share historical growth rate (five year) than the median ranked stock within the company’s GICS sector. The third-party broad-based index currently used to identify growth companies is the Russell 3000® Growth Index, although the Fund may change this index without prior notice. The I/B/E/S is a database used by brokers and investors to access the estimates made by stock analysts regarding the</div> future earnings of publicly traded American companies. The I/B/E/S medium-term growth forecast is a measure of the average annualized EPS (earnings per share) growth forecast of contributing analysts/estimators for the forthcoming two years. <div style="margin-top: 4pt;">Under normal circumstances, the Fund invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in common stocks of U.S. and foreign companies that have market capitalizations in the range of companies in the Russell 1000® Growth Index (the Capitalization Index). The market capitalization range of the companies included within the Capitalization Index was $776.8 million to $4.8 trillion as of June 30, 2026. The market capitalization range and composition of companies in the Capitalization Index are subject to change. As such, the size of the companies in which the Fund invests may change. The Fund may continue to hold a security even if the company’s market capitalization is no longer within the range of the Capitalization Index. The Fund invests primarily in common stocks of companies believed to have the potential for long-term growth. Under normal circumstances, the Fund also invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of “growth” companies. The Fund considers “growth” companies to be those companies that are either constituents of an index constructed by a third party to identify companies with various characteristics of growth companies, have a higher Institutional Brokers' Estimate System (I/B/E/S) medium-term growth forecast (two year) than the median ranked stock within the company’s Global Industry Classification Standard (GICS) sector, or have a higher sales per share historical growth rate (five year) than the median ranked stock within the company’s GICS sector. The third-party broad-based index currently used to identify growth companies is the Russell 3000® Growth Index, although the Fund may change this index without prior notice. The I/B/E/S is a database used by brokers and investors to access the estimates made by stock analysts regarding the</div> <div style="line-height: 12.0pt; text-align: left;">future earnings of publicly traded American companies. The I/B/E/S medium-term growth forecast is a measure of the average annualized EPS (earnings per share) growth forecast of contributing analysts/estimators for the forthcoming two years. 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 directly in foreign securities or indirectly through depositary receipts. The Fund may at times emphasize one or more sectors in selecting its investments. As of its most recent fiscal year end, the Fund had an investment emphasis in the information technology sector.</div> Under normal circumstances, the Fund invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in common stocks of U.S. and foreign companies that have market capitalizationsin the range of companies in the Russell 1000® Growth Index (the Capitalization Index).Under normal circumstances, the Fund also invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of “growth” companies. The market capitalization range of the companies included within the Capitalization Index was $776.8 million to $4.8 trillion as of June 30, 2026.The market capitalization range and composition of companies in the Capitalization Index are subject to change.As such, the size of the companies in which the Fund invests may change. The Fund may continue to hold a security even if the company’s market capitalization is no longer within the range of the Capitalization Index.The Fund invests primarily in common stocks of companies believed to have the potential for long-term growth. The Fund considers “growth” companies to be those companies that are either constituents of an index constructed by a third party to identify companies with various characteristics of growth companies, have a higher Institutional Brokers' Estimate System (I/B/E/S) medium-term growth forecast (two year) than the median ranked stock within the company’s Global Industry Classification Standard (GICS) sector, or have a higher sales per share historical growth rate (five year) than the median ranked stock within the company’s GICS sector. The third-party broad-based index currently used to identify growth companies is the Russell 3000® Growth Index, although the Fund may change this index without prior notice. The I/B/E/S is a database used by brokers and investors to access the estimates made by stock analysts regarding thefuture earnings of publicly traded American companies. The I/B/E/S medium-term growth forecast is a measure of the average annualized EPS (earnings per share) growth forecast of contributing analysts/estimators for the forthcoming two years. 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;">Active Management Risk. Due to its active management, the Fund could underperform its benchmark index and/or other funds with similar investment objectives and/or strategies.</div> <div style="margin-top: 4pt;">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 and/or Global Depositary Receipts. Depositary receipts involve risks similar to the risks associated with investments in foreign securities, including those associated with an issuer’s (and any of its related companies’) country of organization and places of business operations, which may be related to the particular political, regulatory, economic, social and other conditions or events (including, for example, military confrontations and actions, war, other conflicts, terrorism and disease/virus outbreaks and epidemics) occurring in the country and fluctuations in such country’s currency, as well as market risk tied to the underlying foreign company. In addition, holders of depositary receipts may have limited voting rights, may not have the same rights afforded to stockholders of a typical domestic company in the event of a corporate action, such as an acquisition, merger or rights offering, and may experience difficulty in receiving company stockholder communications. There is no guarantee that a financial institution will continue to sponsor a depositary receipt, or that a depositary receipt will continue to trade on an exchange, either of which could adversely affect the liquidity, availability and pricing of the depositary receipt. Changes in foreign currency exchange rates will affect the value of depositary receipts and, therefore, may affect the value of your investment in the Fund.</div> <div style="margin-top: 4pt;">Equity Securities Risk. Equity securities may experience significant volatility. Such securities may fall sharply in response to adverse events affecting overall markets, a particular industry or sector, or an individual company’s financial condition.</div> <div style="margin-top: 4pt;">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.</div> <div style="margin-top: 4pt;">Foreign Securities Risk. Investments in or exposure to securities of foreign companies may involve heightened risks relative to investments in or exposure to securities of U.S. companies. Investing in securities of foreign companies subjects the Fund to the risks associated with an issuer’s (and any of its related companies’) country of organization and places of business operations, including risks related to political, regulatory, economic, social, diplomatic and other conditions or events (including, for example, military confrontations and actions, war, other conflicts, terrorism and disease/virus outbreaks and epidemics) occurring in the country or region, as well as risks associated with less developed custody and settlement practices. Foreign securities may be more volatile and less liquid than securities of U.S. companies and are subject to the risks associated with potential imposition of economic and other sanctions against a particular foreign country, its nationals or industries or businesses within the country. In addition, foreign </div> <div style="line-height: 12.0pt; text-align: left;">governments may impose withholding or other taxes on the Fund’s income, capital gains or proceeds from the disposition of foreign securities, which could reduce the Fund’s return on such securities. The performance of the Fund may also be negatively affected by fluctuations in a foreign currency's strength or weakness relative to the U.S. dollar, particularly to the extent the Fund invests a significant percentage of its assets in foreign securities or other assets denominated in currencies other than the U.S. dollar.</div> <div style="margin-top: 4pt;">Growth Securities Risk. Growth securities typically trade at a higher multiple of earnings than other types of equity securities. Accordingly, the market values of growth securities may never reach their expected market values and may decline in price. In addition, growth securities, at times, may not perform as well as value securities or the stock market in general, and may be out of favor with investors for varying periods of time. Growth securities may also be sensitive to movements in interest rates.</div> <div style="margin-top: 4pt;">Issuer Risk. An issuer in which the Fund invests or to which it has exposure may perform poorly or below expectations, and the value of its securities may therefore decline, which may negatively affect the Fund’s performance. Underperformance of an issuer may be caused by poor management decisions, competitive pressures, breakthroughs in technology, reliance on suppliers, labor problems or shortages, corporate restructurings, fraudulent disclosures, natural disasters, military confrontations and actions, war, other conflicts, terrorism, disease/virus outbreaks, epidemics or other events, conditions and factors which may impair the value of your investment in the Fund.</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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 500.00pt;">Large-Cap Stock Risk. Investments in larger, more established companies (larger companies) may involve certain risks associated with their larger size. For instance, larger companies may be less able to respond quickly to new competitive challenges, such as changes in consumer tastes or innovation from smaller competitors. Also, larger companies are sometimes less able to achieve as high growth rates as successful smaller companies, especially during extended periods of economic expansion.</div> </div> <div style="clear: both; position: relative;"> </div> </div> <div style="margin-top: 4pt;">Market Risk. The Fund may incur losses due to declines in the value of one or more securities in which it invests. These declines may be due to factors affecting a particular issuer, or the result of, among other things, political, regulatory, market, economic or social developments affecting the relevant market(s) more generally. In addition, turbulence in financial markets and reduced liquidity in equity, credit and/or fixed income markets may negatively affect many issuers, which could adversely affect the Fund’s ability to price or value hard-to-value assets in thinly traded and closed markets and could cause significant redemptions and operational challenges. Global economies and financial markets are increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. These risks may be magnified if certain events or developments adversely interrupt the global supply chain; in these and other circumstances, such risks might affect companies worldwide. As a result, local, regional or global events such as terrorism, war, other conflicts, natural disasters, disease/virus outbreaks and epidemics or other public health issues, recessions, depressions or other events – or the potential for such events – could have a significant negative impact on global economic and market conditions.</div> <div style="margin-top: 4pt;">Sector Risk. At times, the Fund may have a significant portion of its assets invested in securities of companies conducting business in a related group of industries within one or more economic sectors, including the information technology sector. Companies in the same sector may be similarly affected by economic, regulatory, political or market events or conditions, which may make the Fund vulnerable to unfavorable developments in that group of industries or economic sector.</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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 500.00pt;">Information Technology Sector. The Fund is vulnerable to the particular risks that may affect companies in the information technology sector. Companies in the information technology sector are subject to certain risks, including the risk that new services, equipment or technologies will not be accepted by consumers and businesses or will become rapidly obsolete. Performance of such companies may be affected by factors including obtaining and protecting patents (or the failure to do so) and significant competitive pressures, including aggressive pricing of their products or services, new market entrants, competition for market share and short product cycles due to an accelerated rate of technological developments. Such competitive pressures may lead to limited earnings and/or falling profit margins. As a result, the value of their securities may fall or fail to rise. In addition, many information technology sector companies have limited operating histories and prices of these </div> </div> <div style="clear: both; position: relative;"> </div> </div> <div style="line-height: 12.0pt; margin-left: 11pt; text-align: left;">companies’ securities historically have been more volatile than other securities, especially over the short term. Some companies in the information technology sector are facing increased government and regulatory scrutiny and may be subject to adverse government or regulatory action, which could negatively impact the value of their securities.</div> Performance Information <div style="margin-top: 4pt;">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.</div> <div style="margin-top: 4pt;">The performance of one or more share classes shown in the table below begins before the indicated inception date for such share class. The returns shown for each such share class include the returns of the Fund’s Class Inst shares for periods prior to its inception date.</div> <div style="margin-top: 4pt;">Except for differences in annual returns resulting from differences in expenses and sales charges (where applicable), the share classes of the Fund would have substantially similar annual returns because all share classes of the Fund invest in the same portfolio of securities.</div> <div style="margin-top: 4pt;">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. 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.</div> <div style="margin-top: 4pt;">The Fund’s past performance (before and after taxes) is no guarantee of how the Fund will perform in the future. Updated performance information can be obtained by calling toll-free 800.345.6611 or visiting columbiathreadneedleus.com. </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 Best 2020-06-30 0.3189 Worst 2022-06-30 -0.2357 Year to Date return 2026-06-30 0.0958 Average Annual Total Returns After Applicable Sales Charges (for periods ended December 31, 2025) 2007-09-28 2007-09-28 2007-09-28 0.0427 0.0437 0.1135 -0.0426 -0.0117 0.0584 0.0819 0.0267 0.0794 1997-10-01 0.1086 0.0587 0.1229 2012-11-08 0.1097 0.0597 0.1240 2012-11-08 0.1099 0.0602 0.1245 2004-12-31 0.1046 0.0537 0.1174 2024-10-02 0.1086 0.0587 0.1229 0.1856 0.1532 0.1813 0.1737 0.1359 0.1459 Summary of the Fund Investment Objective <div style="margin-top: 4pt;">Multi-Manager Large Cap Growth Strategies Fund (the Fund) seeks long-term capital appreciation.</div> Fees and Expenses of the Fund <div style="margin-top: 4pt;">This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below. </div> Shareholder Fees (fees paid directly from your investment) 0 0 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0064 0.0000 0.0010 0.0074 -0.0002 0.0072 Other expenses have been restated to reflect current fees paid by the Fund. July 31, 2027 Example <div style="margin-top: 6pt;">The following example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example illustrates the hypothetical expenses that you would incur over the time periods indicated, and assumes that: </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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;">you invest $10,000 in the class of Fund shares for the periods indicated, </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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;">you redeem all your shares at the end of the period, </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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;">your investment has a 5% return each year, and </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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 494.00pt;">the Fund’s total annual operating expenses remain the same as shown in the Annual Fund Operating Expenses table above.</div> </div> <div style="clear: both; position: relative;"> </div> </div> <div style="margin-top: 6pt;">Since the waivers and/or reimbursements shown in the Annual Fund Operating Expenses table above expire as indicated in the preceding table, they are only reflected in the 1 year example and the first year of the other examples. Although your actual costs may be higher or lower, based on the assumptions listed above, your costs would be: </div> 74 74 235 235 410 410 917 917 Portfolio Turnover <div style="margin-top: 4pt;">The Fund may pay transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. For the fiscal period from June 2, 2025 (commencement of operations) to March 31, 2026, the Fund’s portfolio turnover rate was 65% of the average value of its portfolio.</div> 0.65 Principal Investment Strategies <div style="margin-top: 4pt;">Under normal circumstances, the Fund invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of large-capitalization companies, primarily common stocks and securities that can be converted into common stocks. These companies have market capitalizations in the range of companies in the Russell 1000® Growth Index (the Capitalization Index), which ranged between $776.8 million and $4.8 trillion as of June 30, 2026. The market capitalization range and composition of companies in the Capitalization Index are subject to change. As such, the size of the companies in which the Fund invests may change. The Fund may continue to hold a security even if the company’s market capitalization is no longer within the range of the Capitalization Index. Under normal circumstances, the Fund also invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of “growth” companies. The Fund considers “growth” companies to be those companies that are either constituents of an index constructed by a third party to identify companies with various characteristics of growth companies, have a higher Institutional Brokers' Estimate System (I/B/E/S) medium-term growth forecast (two year) than the median ranked stock within the company’s Global Industry Classification Standard (GICS) sector, or have a higher sales per share historical growth rate (five year) than the median ranked stock within the company’s GICS sector. The third-party broad-based index currently used to identify growth companies is the Russell 3000® Growth Index, although the Fund may change this index without prior notice. The I/B/E/S is a database used by brokers and investors to access the estimates made by stock analysts regarding the future earnings of publicly traded American companies. The I/B/E/S medium-term growth forecast is a measure of the average annualized EPS (earnings per share) growth forecast of contributing analysts/estimators for the forthcoming two years.</div> <div style="margin-top: 4pt;">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 Fund may invest in U.S. and foreign securities, including emerging market securities. The Fund may invest in foreign securities directly or indirectly through depositary receipts. The Fund may at times emphasize one or more sectors in selecting its investments. The Fund emphasizes the communication services and information technology sectors.</div> <div style="margin-top: 4pt;">The Fund may also invest in exchange-traded funds (ETFs).</div> <div style="margin-top: 4pt;">Columbia Management Investment Advisers, LLC (Columbia Management or the Investment Manager) serves as the investment manager for the Fund. Columbia Management is responsible for providing day-to-day portfolio management of a liquidity strategy sleeve of the Fund and is also responsible for oversight of the Fund’s subadvisers. Each subadviser employs its own large cap growth strategy and investment process in its respective sleeve that Columbia Management believes complement one another in pursuit of the Fund’s investment objective. The Fund’s subadvisers are J.P. Morgan Investment Management Inc. (JPMIM), Loomis, Sayles & Company, L.P. (Loomis Sayles) and Los Angeles Capital Management LLC (Los Angeles Capital). Columbia Management, subject to the oversight of the Fund’s Board of Trustees, determines, in its discretion, the allocation of the Fund’s assets to each sleeve, and may change these allocations at any time. One or more of the Fund’s subadvisers use quantitative methods to identify investment opportunities and construct their portion of the Fund’s portfolio.</div> <div style="margin-top: 4pt;">Under normal circumstances, the Fund invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of large-capitalization companies, primarily common stocks and securities that can be converted into common stocks. These companies have market capitalizations in the range of companies in the Russell 1000® Growth Index (the Capitalization Index), which ranged between $776.8 million and $4.8 trillion as of June 30, 2026. The market capitalization range and composition of companies in the Capitalization Index are subject to change. As such, the size of the companies in which the Fund invests may change. The Fund may continue to hold a security even if the company’s market capitalization is no longer within the range of the Capitalization Index. Under normal circumstances, the Fund also invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of “growth” companies. The Fund considers “growth” companies to be those companies that are either constituents of an index constructed by a third party to identify companies with various characteristics of growth companies, have a higher Institutional Brokers' Estimate System (I/B/E/S) medium-term growth forecast (two year) than the median ranked stock within the company’s Global Industry Classification Standard (GICS) sector, or have a higher sales per share historical growth rate (five year) than the median ranked stock within the company’s GICS sector. The third-party broad-based index currently used to identify growth companies is the Russell 3000® Growth Index, although the Fund may change this index without prior notice. The I/B/E/S is a database used by brokers and investors to access the estimates made by stock analysts regarding the future earnings of publicly traded American companies. The I/B/E/S medium-term growth forecast is a measure of the average annualized EPS (earnings per share) growth forecast of contributing analysts/estimators for the forthcoming two years.</div> Under normal circumstances, the Fund invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of large-capitalization companies, primarily common stocks and securities that can be converted into common stocks.Under normal circumstances, the Fund also invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of “growth” companies. These companies have market capitalizations in the range of companies in the Russell 1000® Growth Index (the Capitalization Index),which rangedbetween $776.8 million and $4.8 trillion as of June 30, 2026.The market capitalization range and composition of companies in the Capitalization Index are subject to change.As such, the size of the companies in which the Fund invests may change. The Fund may continue to hold a security even if the company’s market capitalization is no longer within the range of the Capitalization Index. The Fund considers “growth” companies to be those companies that are either constituents of an index constructed by a third party to identify companies with various characteristics of growth companies, have a higher Institutional Brokers' Estimate System (I/B/E/S) medium-term growth forecast (two year) than the median ranked stock within the company’s Global Industry Classification Standard (GICS) sector, or have a higher sales per share historical growth rate (five year) than the median ranked stock within the company’s GICS sector. The third-party broad-based index currently used to identify growth companies is the Russell 3000® Growth Index, although the Fund may change this index without prior notice. The I/B/E/S is a database used by brokers and investors to access the estimates made by stock analysts regarding the future earnings of publicly traded American companies. The I/B/E/S medium-term growth forecast is a measure of the average annualized EPS (earnings per share) growth forecast of contributing analysts/estimators for the forthcoming two years. 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;">Active Management Risk. Due to its active management, the Fund could underperform its benchmark index and/or other funds with similar investment objectives and/or strategies.</div> <div style="margin-top: 4pt;">Allocation Risk. Because the Fund uses an asset allocation strategy in pursuit of its investment objective, there is a risk that the Fund's allocation among asset classes, investments, managers, strategies and/or investment styles will cause the Fund's shares to lose value or cause the Fund to underperform other funds with similar investment objectives and/or strategies, or that the investments themselves will not produce the returns expected.</div> <div style="margin-top: 4pt;">Convertible Securities Risk. Convertible securities are subject to the usual risks associated with debt instruments, such as interest rate risk and credit risk. Convertible securities also react to changes in the value of the common stock into which they convert and are thus subject to market risk. The Fund may also be forced to convert a convertible security at an inopportune time, which may decrease the Fund’s return.</div> <div style="margin-top: 4pt;">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 and/or Global Depositary Receipts. Depositary receipts involve risks similar to the risks associated with investments in foreign securities, including those associated with an issuer’s (and any of its related companies’) country of organization and places of business operations, which may be related to the particular political, regulatory, economic, social and other conditions or events (including, for example, military confrontations and actions, war, other conflicts, terrorism and disease/virus outbreaks and epidemics) occurring in the country and fluctuations in such country’s currency, as well as market risk tied to the underlying foreign company. In addition, holders of depositary receipts may have limited voting rights, may not have the same rights afforded to stockholders of a typical domestic company in the event of a corporate action, such as an acquisition, merger or rights offering, and may experience difficulty in receiving company stockholder communications. There is no guarantee that a financial institution will continue to sponsor a depositary receipt, or that a depositary receipt will continue to trade on an exchange, either of which could adversely affect the liquidity, availability and pricing of the depositary receipt. Changes in foreign currency exchange rates will affect the value of depositary receipts and, therefore, may affect the value of your investment in the Fund.</div> <div style="margin-top: 4pt;">Emerging Market Securities Risk. Securities issued by foreign governments or companies in emerging market countries, such as China, Russia and certain countries in Eastern Europe, the Middle East, Asia, Latin America or Africa, are more likely to have greater exposure to the risks of investing in foreign securities that are described in Foreign Securities Risk. In addition, emerging market countries are more likely to experience instability resulting, for example, from rapid changes or developments in social, political, economic or other conditions. Their economies are usually less mature and their securities markets are typically less developed with more limited trading activity (i.e., lower trading volumes and less liquidity) than more developed countries. Emerging market securities tend to be more volatile, and may be more susceptible to market manipulation, than securities in more developed markets. Many emerging market countries are heavily dependent on international trade and have fewer trading partners, which makes them more sensitive to world commodity prices and economic downturns in other countries, and some have a higher risk of currency devaluations. Due to the differences in the nature and quality of financial information of issuers of emerging market securities, including auditing and financial reporting standards, financial information and disclosures about such issuers may be unavailable or, if made available, may be considerably less reliable than publicly available information about other foreign securities.</div> <div style="margin-top: 4pt;">Equity Securities Risk. Equity securities may experience significant volatility. Such securities may fall sharply in response to adverse events affecting overall markets, a particular industry or sector, or an individual company’s financial condition.</div> <div style="line-height: 12.0pt; text-align: left;">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.</div> <div style="margin-top: 4pt;">Foreign Securities Risk. Investments in or exposure to securities of foreign companies may involve heightened risks relative to investments in or exposure to securities of U.S. companies. Investing in securities of foreign companies subjects the Fund to the risks associated with an issuer’s (and any of its related companies’) country of organization and places of business operations, including risks related to political, regulatory, economic, social, diplomatic and other conditions or events (including, for example, military confrontations and actions, war, other conflicts, terrorism and disease/virus outbreaks and epidemics) occurring in the country or region, as well as risks associated with less developed custody and settlement practices. Foreign securities may be more volatile and less liquid than securities of U.S. companies and are subject to the risks associated with potential imposition of economic and other sanctions against a particular foreign country, its nationals or industries or businesses within the country. In addition, foreign governments may impose withholding or other taxes on the Fund’s income, capital gains or proceeds from the disposition of foreign securities, which could reduce the Fund’s return on such securities. The performance of the Fund may also be negatively affected by fluctuations in a foreign currency's strength or weakness relative to the U.S. dollar, particularly to the extent the Fund invests a significant percentage of its assets in foreign securities or other assets denominated in currencies other than the U.S. dollar.</div> <div style="margin-top: 4pt;">Growth Securities Risk. Growth securities typically trade at a higher multiple of earnings than other types of equity securities. Accordingly, the market values of growth securities may never reach their expected market values and may decline in price. In addition, growth securities, at times, may not perform as well as value securities or the stock market in general, and may be out of favor with investors for varying periods of time. Growth securities may also be sensitive to movements in interest rates.</div> <div style="margin-top: 4pt;">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. Due to the expenses and costs of an underlying fund being 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. The Investment Manager has a conflict of interest in selecting affiliated underlying funds over unaffiliated underlying funds because it receives management fees from affiliated underlying funds, and it has a conflict in selecting among affiliated underlying funds, because the fees paid to it by certain affiliated underlying funds are higher than the fees paid by other affiliated 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 is not identified in a timely manner or at all. The underlying funds may not achieve their investment objective. The Fund, through its investment in underlying funds, may not achieve its investment objective.</div> <div style="margin-top: 4pt;">Issuer Risk. An issuer in which the Fund invests or to which it has exposure may perform poorly or below expectations, and the value of its securities may therefore decline, which may negatively affect the Fund’s performance. Underperformance of an issuer may be caused by poor management decisions, competitive pressures, </div> <div style="line-height: 12.0pt; text-align: left;">breakthroughs in technology, reliance on suppliers, labor problems or shortages, corporate restructurings, fraudulent disclosures, natural disasters, military confrontations and actions, war, other conflicts, terrorism, disease/virus outbreaks, epidemics or other events, conditions and factors which may impair the value of your investment in the Fund.</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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 500.00pt;">Large-Cap Stock Risk. Investments in larger, more established companies (larger companies) may involve certain risks associated with their larger size. For instance, larger companies may be less able to respond quickly to new competitive challenges, such as changes in consumer tastes or innovation from smaller competitors. Also, larger companies are sometimes less able to achieve as high growth rates as successful smaller companies, especially during extended periods of economic expansion.</div> </div> <div style="clear: both; position: relative;"> </div> </div> <div style="margin-top: 4pt;">Market Risk. The Fund may incur losses due to declines in the value of one or more securities in which it invests. These declines may be due to factors affecting a particular issuer, or the result of, among other things, political, regulatory, market, economic or social developments affecting the relevant market(s) more generally. In addition, turbulence in financial markets and reduced liquidity in equity, credit and/or fixed income markets may negatively affect many issuers, which could adversely affect the Fund’s ability to price or value hard-to-value assets in thinly traded and closed markets and could cause significant redemptions and operational challenges. Global economies and financial markets are increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. These risks may be magnified if certain events or developments adversely interrupt the global supply chain; in these and other circumstances, such risks might affect companies worldwide. As a result, local, regional or global events such as terrorism, war, other conflicts, natural disasters, disease/virus outbreaks and epidemics or other public health issues, recessions, depressions or other events – or the potential for such events – could have a significant negative impact on global economic and market conditions.</div> <div style="margin-top: 4pt;">Multi-Adviser Risk. The Fund has multiple advisory firms that each manage a portion of the Fund’s net assets on a daily basis. Each adviser makes investment decisions independently from the other adviser(s). It is possible that the security selection process of one adviser will not complement or may conflict or even contradict that of the other adviser(s), including making offsetting trades that have no net effect to the Fund, but which may increase Fund expenses. As a result, the Fund's exposure to a given security, industry, sector or market capitalization could be smaller or larger than if the Fund were managed by a single adviser, which could adversely affect the Fund's performance.</div> <div style="margin-top: 4pt;">Non-Diversified Fund Risk. The Fund is non-diversified, which generally means that it may invest a greater percentage of its total assets in the securities of fewer issuers than a “diversified” fund. This increases the risk that a change in the value of any one investment held by the Fund could affect the overall value of the Fund more than it would affect that of a diversified fund holding a greater number of investments. Accordingly, the Fund's value will likely be more volatile than the value of a more diversified fund.</div> <div style="margin-top: 4pt;">Quantitative Models Risk. Quantitative models used by the Fund may not effectively identify purchases and sales of Fund investments and may cause the Fund to underperform other investment strategies. Flaws or errors in the quantitative model’s assumptions, design, execution, or data inputs may adversely affect Fund performance. Quantitative models may not perform as expected and may underperform in certain market environments including in stressed or volatile market conditions. There can be no assurance that the use of quantitative models will enable the Fund to achieve its objective.</div> <div style="margin-top: 4pt;">Sector Risk. At times, the Fund may have a significant portion of its assets invested in securities of companies conducting business in a related group of industries within one or more economic sectors, including the communication services and information technology sectors. Companies in the same sector may be similarly affected by economic, regulatory, political or market events or conditions, which may make the Fund vulnerable to unfavorable developments in that group of industries or economic sector.</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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 500.00pt;">Communication Services Sector. The Fund is vulnerable to the particular risks that may affect companies in the communication services sector. Companies in the communication services sector are subject to certain risks, including the risk that new services, equipment or technologies will not be accepted by consumers and businesses or will become rapidly obsolete. Performance of such companies may be affected by factors including </div> </div> <div style="clear: both; position: relative;"> </div> </div> <div style="line-height: 12.0pt; margin-left: 11pt; text-align: left;">obtaining and protecting patents (or the failure to do so) and significant competitive pressures, including aggressive pricing of their products or services, new market entrants, competition for market share and short product cycles due to an accelerated rate of technological developments. Such competitive pressures may lead to limited earnings and/or falling profit margins. As a result, the value of their securities may fall or fail to rise. In addition, many communication services sector companies have limited operating histories and prices of these companies’ securities historically have been more volatile than other securities, especially over the short term.</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;">■</div> <div style="float: left; line-height: 12pt; margin-left: 6.55pt; text-align: left; width: 500.00pt;">Information Technology Sector. The Fund is vulnerable to the particular risks that may affect companies in the information technology sector. Companies in the information technology sector are subject to certain risks, including the risk that new services, equipment or technologies will not be accepted by consumers and businesses or will become rapidly obsolete. Performance of such companies may be affected by factors including obtaining and protecting patents (or the failure to do so) and significant competitive pressures, including aggressive pricing of their products or services, new market entrants, competition for market share and short product cycles due to an accelerated rate of technological developments. Such competitive pressures may lead to limited earnings and/or falling profit margins. As a result, the value of their securities may fall or fail to rise. In addition, many information technology sector companies have limited operating histories and prices of these companies’ securities historically have been more volatile than other securities, especially over the short term. Some companies in the information technology sector are facing increased government and regulatory scrutiny and may be subject to adverse government or regulatory action, which could negatively impact the value of their securities.</div> </div> <div style="clear: both; position: relative;"> </div> </div> Performance Information <div style="margin-top: 4pt;">The Fund has not had a full calendar year of operations as of the date of this prospectus and therefore performance information is not available. </div> <div style="margin-top: 4pt;">When available, the Fund intends to compare its performance to the performance of the Russell 1000® Growth Index, as well as the Russell 1000® Index. </div> <div style="margin-top: 4pt;">Updated performance information can be obtained by calling toll-free 800.345.6611 or visiting columbiathreadneedleus.com.</div> The Fund has not had a full calendar year of operations as of the date of this prospectus and therefore performance information is not available. 800.345.6611 columbiathreadneedleus.com Year to Date return as of June 30, 2026: 7.04% Year to Date return as of June 30, 2026: 9.58% Other expenses have been restated to reflect current fees paid by the Fund. 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 July 31, 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 rate of 0.72% for Class Inst. Any difference in the annual rate relative to the annual rate noted in the last row of the above table (e.g., net expense ratio) is due to applicable exclusions under the agreement. Returns shown for periods prior to the inception date of the Class Inst shares include the returns of the Fund’s Class A shares through January 2, 2017. Class A shares were offered prior to the inception date of the Fund’s Class Inst shares but have since been merged into the Fund’s Class Inst shares. Management fees have been restated to reflect current fees based on current asset levels. 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. Management fees have been restated to reflect current fees based on current asset levels. Other expenses have been restated and are based on estimated amounts for the Fund’s current fiscal year, taking into consideration changes in the Fund’s net assets. “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. “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. Other expenses have been restated to reflect current fees paid by the Fund. 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 July 31, 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 1.01% for Class A, 0.76% for Class Inst, 0.70% for Class Inst2, 0.65% for Class Inst3, 1.26% for Class R and 0.76% 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. 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 July 31, 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 rate of 0.72% for Class Inst. Any difference in the annual rate relative to the annual rate noted in the last row of the above table (e.g., net expense ratio) is due to applicable exclusions under the agreement.