UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE

SECURITIES EXCHANGE ACT OF 1934

Filed by the Registrant  ☒                             Filed by a party other than the Registrant  ☐

Check the appropriate box:

Columbia Funds Series Trust

(Name of Registrant as Specified in its Charter)

Payment of Filing Fee (Check the appropriate box):

COLUMBIA ETF TRUST I

COLUMBIA ETF TRUST II

COLUMBIA FUNDS SERIES TRUST

COLUMBIA FUNDS SERIES TRUST I

COLUMBIA FUNDS SERIES TRUST II

225 Franklin Street, Boston, Massachusetts 02110

IMPORTANT INFORMATION TO HELP YOU UNDERSTAND AND VOTE ON THE PROPOSAL

This is a brief overview of the matter on which you are being asked to vote.

The accompanying Joint Proxy Statement contains more detailed information about the proposal, and we encourage you to read it in its entirety before voting. Your vote is important.

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The enclosed Joint Proxy Statement also serves as notice to shareholders of the Funds of recent amendments to the Declaration of Trust and By-Laws of each Trust relating to virtual meetings, as well as certain governance changes in connection with the board consolidation described below. See the section of the enclosed Joint Proxy Statement entitled “The Proposal – Election of Trustees – Recent Amendments to Declarations of Trust and By-Laws” for additional information regarding these amendments.

Each Board has separately determined that it is in the best interests of the funds overseen by such Board, including the Funds, to align and consolidate the membership of the Boards so that the funds are overseen by a single board. Accordingly, the Boards recommend the seventeen (17) individuals listed in the enclosed Joint Proxy Statement for election to the Board of each Trust. The same nominees have been recommended to shareholders for all open-end funds overseen by such Boards, so that if all nominees are approved by shareholders, the proposed combined board would oversee nearly all of the open-end funds and exchange-traded funds advised by Columbia Threadneedle, which include 174 open-end funds with assets of approximately $310 billion as of September 30, 2020, including fund-of-fund assets.

In reaching its conclusion each Board considered, among other things, that while the proposed combined board would be larger than either current Board, reducing the number of separate boards overseeing a fund complex can lead to operational efficiencies and decreased costs for the funds in the complex, as well as provide operational efficiencies and decreased costs for Columbia Threadneedle by streamlining the resources needed for Board support.

Additional information regarding each nominee and the proposal is set forth in the enclosed Joint Proxy Statement.

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We encourage you to vote as soon as possible. Please refer to the enclosed Proxy Card for information on voting by telephone, Internet or mail.

The Meeting will be a completely virtual meeting of shareholders, which will be conducted exclusively by webcast. You are entitled to participate in the Meeting only (i) if you were a shareholder of a Fund that is a series of CFST, CFST I and CFST II as of the close of business on October 9, 2020, (ii) if you were a shareholder of a Fund that is a series of CETF I and CETF II as of the close of business on October 16, 2020 or (iii) if you hold a valid proxy for the Meeting. No physical meeting will be held.

You will be able to attend the Meeting online and submit your questions during the Meeting by visiting www.meetingcenter.io/272705013. You also will be able to vote your shares online by attending the Meeting by webcast. To participate in the Meeting, you will need to log on using the control number from your Proxy Card or Meeting notice. The control number can be found in the shaded box. The password for the Meeting is COL2020.

If you hold your shares through an intermediary, such as a bank or broker, you must register in advance using the instructions below. The online Meeting will begin promptly at 10:00 a.m., Eastern time, on December 22, 2020. We encourage you to access the Meeting prior to the start time leaving ample time for the check in. Please follow the access instructions as outlined herein.

If your shares are registered in your name, you do not need to register to attend the Meeting virtually on the Internet. If you hold your shares through an intermediary, such as a bank or broker, you must register in advance to attend the Meeting virtually on the Internet. To register to attend the Meeting online by webcast you must submit proof of your proxy power (legal proxy) reflecting your Fund holdings along with your name and email address to Computershare. You must contact the intermediary that holds your shares to obtain your legal proxy. Requests for registration must be labeled as “Legal Proxy” and be received no later than 5:00 p.m., Eastern time, three (3) business days prior to the Meeting date.

You will receive a confirmation of your registration by email after we receive your registration materials.

Requests for registration should be directed to us by emailing an image of your legal proxy to shareholdermeetings@computershare.com.

In light of the public health concerns regarding the coronavirus (COVID-19) pandemic, we believe that hosting a virtual meeting is in the best interests of the Funds and their shareholders.

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NOTICE OF A JOINT SPECIAL MEETING OF SHAREHOLDERS

COLUMBIA ETF TRUST I

COLUMBIA ETF TRUST II

COLUMBIA FUNDS SERIES TRUST

COLUMBIA FUNDS SERIES TRUST I

COLUMBIA FUNDS SERIES TRUST II

To be held on December 22, 2020

A Joint Special Meeting of Shareholders (the “Meeting”) of the funds listed above (each, a “Fund” and collectively, the “Funds”) will be held on December 22, 2020 at 10:00 a.m. (Eastern time). The Board of Trustees (each, a “Board,” and together, the “Boards”) of each of Columbia ETF Trust I (“CETF I”), Columbia ETF Trust II (“CETF II”), Columbia Funds Series Trust (“CFST”), Columbia Funds Series Trust I (“CFST I”) and Columbia Funds Series Trust II (“CFST II”) (each, a “Trust,” and together, the “Trusts”) has recommended certain individuals for election to each Board. At the Meeting, shareholders of each series of each Trust will be asked to consider the following proposal:

In light of the public health concerns regarding the coronavirus (COVID-19) pandemic, the Meeting will be held in a virtual meeting format only, which will be conducted online via live webcast. Shareholders may attend and vote at the virtual Meeting by following the instructions included in the enclosed Q&A and Joint Proxy Statement.

Please take some time to read the enclosed Joint Proxy Statement. It discusses the proposal in more detail. If, as of the close of business on October 9, 2020, you were a shareholder of a Fund that is a series of CFST, CFST I or CFST II, or if, as of the close of business on October 16, 2020, you were a shareholder of a Fund that is as series of CETF I and CETF II, you may vote at the Meeting or at any adjournment or postponement of the Meeting. If you have questions, please call the Funds’ proxy solicitor toll free at 866-905-2396. It is important that you vote. You may vote by mail, by phone or over the Internet. The Boards unanimously recommend that you vote FOR the election of the trustee nominees.

COLUMBIA ETF TRUST I

COLUMBIA ETF TRUST II

COLUMBIA FUNDS SERIES TRUST

COLUMBIA FUNDS SERIES TRUST I

COLUMBIA FUNDS SERIES TRUST II

225 Franklin Street, Boston, Massachusetts 02110

JOINT PROXY STATEMENT

Joint Special Meeting of Shareholders to be held on December 22, 2020

This Joint Proxy Statement is furnished to you in connection with the solicitation of proxies by the Board of Trustees (each, a “Board,” and together, the “Boards” and each trustee, a “Trustee” and collectively, the “Trustees”) of each of Columbia ETF Trust I (“CETF I”), Columbia ETF Trust II (“CETF II”), Columbia Funds Series Trust (“CFST”), Columbia Funds Series Trust I (“CFST I”) and Columbia Funds Series Trust II (“CFST II,” and together with CETF I, CETF II, CFST and CFST I, the “Trusts” and each, a “Trust”), relating to the joint special meeting of shareholders (the “Meeting”) of the Funds listed above, that will be held on December 22, 2020 at 10:00 a.m. (Eastern time) and any adjournments or postponements thereof. The enclosed proxy card (“Proxy Card”) and this Joint Proxy Statement are first being sent to shareholders of the Funds on or about October 28, 2020. Each Board has determined that the use of this Joint Proxy Statement for the Meeting is in the best interest of each Fund and its shareholders in light of the similar matters being considered and voted on by the shareholders. The purpose of the Meeting is to ask shareholders to elect seventeen (17) nominees to the Board of each Trust who have agreed to stand for election (the “Nominees”), each to hold office until he or she dies, retires, resigns or is removed or, if sooner, until the election and qualification of his or her successor.

Because of public health concerns regarding the coronavirus (COVID-19) pandemic, the Meeting will be held in a virtual meeting format only, which will be conducted online via live webcast. You will be able to attend and participate in the Meeting online, vote your shares electronically and submit your questions prior to and during the Meeting by visiting: www.meetingcenter.io/272705013 at the Meeting date and time. If your shares are registered in your name, to participate in the Meeting, you will need to log on using the control number from your Proxy Card or Meeting notice. The control number can be found in the shaded box. The password for the Meeting is COL2020. There is no physical location for the Meeting.

If you hold your shares through an intermediary, such as a bank or broker, you must register in advance to attend the Meeting online by webcast. To register to attend the Meeting online by webcast you must submit proof of your proxy power (legal proxy) reflecting your Fund holdings along with your name and email address to Computershare Fund Services. You must contact the intermediary that holds your shares to obtain your legal proxy. Requests for registration must be labeled as “Legal Proxy” and be received no later than 5:00 p.m., Eastern time, three (3) business days prior to the Meeting date. You will receive a confirmation of your registration by email after we receive your registration materials. Requests for registration should be directed to us by emailing an image of your legal proxy to shareholdermeetings@computershare.com.

Shareholders of record for each Fund that is a series of CFST, CFST I and CFST II at the close of business on October 9, 2020 and for each Fund that is a series of CEFT I and CETF II at the close of business on October 16, 2020 (each such date, a “Record Date” and collectively, the “Record Dates”) are entitled to notice of, and to vote at, the Meeting. The number of outstanding shares of each class of shares of each Fund held on the applicable Record Date is listed in Appendix A. Persons that, to the knowledge of the Funds, owned beneficially 5% or more of the outstanding shares of any class of each Fund as of the applicable Record Date are listed in Appendix B. The fiscal year-end for each Fund is listed in Appendix C.

It is expected that the solicitation of proxies will be primarily by mail. However, shareholders will not automatically receive a copy of this Joint Proxy Statement in the mail, but will instead receive a notice that informs them how to access all of the proxy materials on a publicly available website (commonly referred to as “notice and access”). Shareholders who receive such a notice will not be able to return the notice to have their vote recorded. Instead, shareholders can access the proxy materials at https://www.proxy-direct.com/col-31702 to vote eligible shares or may use the instructions on the notice to request a paper or email copy of the proxy materials at no charge.

Additional information about each Fund is available in the Fund’s prospectus, statement of additional information and annual and semiannual reports to shareholders. Each Fund’s most recent annual and semiannual reports have previously been delivered to shareholders. Additional copies of any of these documents are available without charge upon request by writing to Columbia Funds, c/o Columbia Management Investment Services Corp., P.O. Box 219104, Kansas City, MO 64121-9104 or by calling (800) 345-6611. All of these documents are also filed with the U.S. Securities and Exchange Commission (the “SEC”) and are available on the SEC’s website at www.sec.gov.

Important Notice Regarding the Availability of Proxy Materials for the Shareholder Meeting to Be Held on December 22, 2020. This Joint Proxy Statement and the Notice of Joint Special Meeting are available at https://www.proxy-direct.com/col-31702.

EACH BOARD UNANIMOUSLY RECOMMENDS THAT SHAREHOLDERS VOTE FOR THE ELECTION OF EACH NOMINEE FOR ITS TRUST(S)

TABLE OF CONTENTS

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THE PROPOSAL — ELECTION OF TRUSTEES

At the Meeting, shareholders of all Funds will be asked to elect seventeen (17) Nominees to constitute the Board of their Trust, effective January 1, 2021. The election of these Nominees will allow for the combined oversight of the Funds under a single Board.

At present, the Funds and certain other funds advised by Columbia Management Investment Advisers, LLC (“Columbia Threadneedle” or the “Investment Manager”) are overseen by two separate boards of trustees. The Funds within CFST I (the “Atlantic Trust”) are overseen by seven Trustees and three Consultants (as defined below) comprising the “Columbia Atlantic Board” and the Funds within CETF I, CETF II, CFST and CFST II (collectively, the “Columbia Trusts”) are overseen by ten Trustees comprising the “Columbia Funds Board.”

Each Board has separately determined that it is in the best interests of the funds overseen by such Board, including the Funds, to align and consolidate the membership of the Boards so that the funds are overseen by the Nominees as a single board. Accordingly, the Boards recommend the seventeen (17) individuals listed in this Joint Proxy Statement for election to the Board of each Trust, each to hold office until he or she dies, retires, resigns or is removed or, if sooner, until the election and qualification of his or her successor. The Boards have also approved the same nominees for all open-end funds overseen by such Boards, so that if all nominees are approved by shareholders, the proposed combined board would oversee nearly all of the open-end funds and exchange-traded funds advised by Columbia Threadneedle, which include 174 open-end funds with assets of approximately $310 billion as of September 30, 2020, including fund-of-fund assets.

In reaching its conclusion each Board considered, among other things, that while the proposed combined board would be larger than either current Board, reducing the number of separate boards overseeing a fund complex can lead to operational efficiencies and decreased costs for the funds in the complex, as well as provide operational efficiencies and decreased costs for Columbia Threadneedle by streamlining the resources needed for Board support.

Each Board is responsible for overseeing the management of the applicable Trust(s). Each Nominee currently serves as a Trustee or Consultant of either the Atlantic Trust or the Columbia Trusts. Due to planned retirements, John J. Neuhauser and Patrick J. Simpson, each of whom serves as a Trustee on the Columbia Atlantic Board, are not standing for reelection to serve on the combined Board. Christopher O. Petersen (the “Interested Nominee”) has been nominated to serve as a Trustee for the Trusts and will be treated as an “interested person” of the Funds due to his positions with Columbia Threadneedle and Ameriprise Financial, Inc. Upon the election and qualification of Mr. Petersen, William F. Truscott, who currently serves as Trustee of the Trusts and is currently treated as an “interested person” of the Funds, will resign from the Boards, although Mr. Truscott will remain a Senior Vice President of the Trusts and his position with Columbia Threadneedle remains unaffected.

The Investment Company Act of 1940 (the “1940 Act”) and rules adopted thereunder contain provisions requiring that certain percentages of a mutual fund’s board of directors consist of individuals who are independent of the mutual fund or its adviser within the meaning of Section 2(a)(19) of the 1940 Act (the “Independent Trustees”). Current regulations applicable to the Funds require that a majority of each Trust’s Board consist of Independent Trustees. A Nominee is deemed to be “independent” to the extent the Nominee is not an “interested person” of the Funds, as that term is defined in Section 2(a)(19) of the 1940 Act (the “Independent Nominees”). The Independent Nominees are George S. Batejan, Kathleen Blatz, Pamela G. Carlton, Janet Langford Carrig, J. Kevin Connaughton, Olive Darragh, Patricia M. Flynn, Brian J. Gallagher, Douglas A. Hacker, Nancy T. Lukitsh, David M. Moffett, Catherine James Paglia, Anthony M. Santomero, Minor M. Shaw, Natalie A. Trunow and Sandra Yeager.

Mses. Darragh and Trunow and Mr. Connaughton currently serve as consultants to the Independent Trustees of the Atlantic Trust (the “Consultants to the Independent Trustees” or “Consultants”), and each participate in

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Board and committee meetings but do not have the right to vote on matters before the Trustees. If elected, the Consultants to the Independent Trustees will serve as Independent Trustees.

At a meeting held on October 2, 2020, the Governance Committee of the Atlantic Trust (all of whose members are Independent Trustees) nominated the Independent Nominees and recommended that the Columbia Atlantic Board nominate the Interested Nominee. At a meeting held on October 2, 2020, the Independent Trustees of the Atlantic Trust accepted, endorsed and approved the Independent Nominees presented by the Governance Committee and the Columbia Atlantic Board nominated the Interested Nominee and voted to recommend each of the Independent Nominees and the Interested Nominee to shareholders for election as Trustees. Likewise, at a meeting held on October 1, 2020, the Board Governance Committee of the Columbia Trusts (all of whose members are Independent Trustees) nominated the Independent Nominees and recommended that the Columbia Funds Board nominate the Interested Nominee. At a meeting held on October 1, 2020, the Columbia Funds Board accepted, endorsed and approved the Independent Nominees presented by the Board Governance Committee, nominated the Interested Nominee and voted to recommend each of the Independent Nominees and the Interested Nominee to shareholders for election as Trustees. The Boards currently have no reason to believe that any Nominee will become unable to serve or for good cause will not serve as a trustee, but if that should occur before the Meeting, the proxies may be voted for such other Nominees as each Trust’s present Governance Committee and/or the Board may select. If the Nominees are elected by shareholders, at least 75% of the trustees will continue to be Independent Trustees (currently 90% of the Columbia Funds Board and 86% of the Columbia Atlantic Board is comprised of Independent Trustees).

If the Nominees are elected by shareholders, the Funds will begin to operate under the oversight of the combined board on January 1, 2021. After careful consideration of the proposed governance structure of the combined board, and to ensure continuity of various aspects of the governance of each Fund overseen by the combined board, the Boards have agreed that if the Nominees are elected by shareholders of the Trusts, for a one-year transition period starting January 1, 2021, each Board committee would be co-chaired by a member of each legacy Board with the exception of the Board Governance Committee, which will have one chair (the current Board Governance Committee chair of the Columbia Funds Board) due to the planned retirement of the current Governance Committee chair of Columbia Atlantic Fund at the end of this year, and that Mr. Hacker and Ms. Paglia, each of whom is an Independent Trustee, will serve as co-Chairs of the combined board for a two-year transition period ending December 31, 2022. Further, the Boards agreed to implement certain other governance provisions, including that the affirmative vote of at least 66 2/3% of the trustees then in office would be required to materially change the committee structure (including the committee chairs) or to remove a trustee, with or without cause.

Recent Amendments to Declarations of Trust and By-Laws

In connection with the proposed election of a combined board, the Board of each Trust has approved an amendment of its Declaration of Trust to include various provisions regarding Board governance agreed to by the Boards, and to clarify the Trust’s ability to hold virtual shareholder meetings. In addition, each Trust’s By-Laws were amended to make the indemnification provisions more consistent across the Trusts and other funds to be overseen by the combined Board. For more information on the amendments to the Trusts’ Declarations of Trust and By-Laws see Appendix D.

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Information Regarding the Nominees

Background information regarding each of the Nominees follows.*

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Current Status of Trustees/Nominees

With regard to the Atlantic Trust, Ms. Carrig, Dr. Neuhauser and Messrs. Hacker and Simpson were most recently elected by shareholders to be Trustees in 2010. Ms. Lukitsh and Mr. Moffett were appointed by the Board as Trustees to fill vacancies in 2011. Mr. Truscott was appointed by the Board as a Trustee in 2012. Mr. Connaughton and Ms. Trunow were appointed by the Board as Consultants to the Independent Trustees in 2016. Ms. Darragh was appointed by the Board as a Consultant to the Independent Trustees in 2019.

With regard to the Columbia Trusts, Mses. Blatz, Carlton, Flynn, Paglia and Shaw and Messrs. Santomero and Truscott were most recently elected by shareholders to be Trustees of CFST and CFST II in February 2011, were elected by consent of the initial shareholder to be Trustees of CETF I in April 2016 and were most recently elected by shareholders to be Trustees of CETF II in August 2016. Messrs. Batejan and Gallagher and Ms. Yeager were appointed by the Board as Trustees of CFST, CFST II, CETF I and CETF II to fill vacancies in January 2017.

Each currently serving Trustee, except for Dr. Neuhauser and Messrs. Simpson and Truscott, is standing for election at the Meeting and has agreed to continue to serve if elected. Mr. Truscott will resign from the Boards upon election and qualification of Mr. Petersen, although Mr. Truscott will remain a Senior Vice President of the Trusts and his position with the Investment Manager remains unaffected. Dr. Neuhauser and Mr. Simpson are not

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standing for election due to the retirement policy of the Atlantic Trust and are expected to retire as Trustees of the Atlantic Trust effective December 31, 2020. Under each Board’s current retirement policy, each Trustee generally serves until December  31 of the year such Trustee turns seventy-five (75).

Nominee Qualifications

The following provides an overview of the considerations that led each Board to conclude that each individual serving or nominated to serve as a trustee should so serve. Generally, no one factor was decisive in the selection of an individual to join the Boards. Among the factors the Boards considered when concluding that an individual should serve on the Boards were the following: (i) the individual’s business and professional experience and accomplishments; (ii) the individual’s ability to work effectively with the other Trustees/Nominees; (iii) the individual’s prior experience, if any, serving on the boards of public companies (including, where relevant, other investment companies) and other complex enterprises and organizations; and (iv) how the individual’s skills, experience and attributes would contribute to an appropriate mix of relevant skills and experience on the Boards.

In respect of each Nominee, the individual’s substantial professional accomplishments and experience, including in fields related to the operations of the Funds, were a significant factor in the determination that, in light of the business and structure of the Trusts, the individual should serve as a trustee. Following is a summary of each Nominee’s particular professional experience and additional considerations that contributed to or support the Boards’ conclusion that an individual should serve as a trustee:

George S. Batejan – Mr. Batejan has over 40 years’ experience in the financial services industry, including service as a former Executive Vice President and Global Head of Technology and Operations of Janus Capital Group, Inc. He has also served as Senior Vice President and Chief Information Officer of Evergreen Investments, Inc., Executive Vice President and Chief Information Officer of OppenheimerFunds, Inc., and Head of International Property and Casualty Operations and Systems/Senior Vice President of American International Group. Mr. Batejan is an 18-year veteran of Chase Manhattan Bank, N.A. where he progressed to Private Banking Vice President and Division Executive of the Americas’ Service Delivery Group. He has also served on numerous corporate and non-profit boards. Mr. Batejan has also served as Chair of the National Investment Company Service Association (NICSA). Additionally, Mr. Batejan has managed operational units supporting the mutual fund business. These functions include fund accounting, fund treasury, fund tax, transfer agent, trade processing and settlement, proxy voting, corporate actions, operational risk, business continuity, and cyber security. He was also a member of the Ethics Committee, Global Risk Committee, and Cyber Security Committee of a major investment manager.

Kathleen Blatz – Ms. Blatz has had a successful legal and judicial career, including serving for eight years as Chief Justice of the Minnesota Supreme Court. Prior to being a judge, she practiced law and also served in the Minnesota House of Representatives having been elected to eight terms. While in the legislature she served on various committees, including the Financial Institutions and Insurance Committee and the Tax Committee. Since retiring from the Bench, she has been appointed as an arbitrator on many cases involving business to business disputes, including some pertaining to shareholder rights issues. She also has been appointed to two Special Litigation Committees by boards of Fortune 500 Companies to investigate issues relating to cyber-security and stock options. In February 2018, she was appointed Interim President and Chief Executive Officer of Blue Cross and Blue Shield of Minnesota and served in that capacity until July 30, 2018. She also serves on the board of directors of Blue Cross and Blue Shield of Minnesota, and as chair of a non-profit organization.

Pamela G. Carlton – Ms. Carlton has over 20 years’ experience in the investment banking industry, as a former Managing Director of JP Morgan Chase and a 14-year veteran of Morgan Stanley Investment Banking and Equity Research. She is currently the President of Springboard Partners in Cross Cultural Leadership, a consulting firm that she founded. Ms. Carlton also serves on the Board of Directors of DR Bank (formerly Laurel Road Bank), a privately held community bank, where she serves on the Audit Committee. She also serves on the

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board of directors of Evercore Inc., a public investment bank. In addition, she has experience on other boards of directors of non-profit organizations, including the Board of Trustees of New York Presbyterian Hospital where she is on the Executive Committee and Chair of the Human Resources Committee.

Janet Langford Carrig – Ms. Carrig was Senior Vice President, General Counsel and Corporate Secretary for ConocoPhillips. Prior to joining ConocoPhillips, Ms. Carrig held senior legal and leadership roles in other large corporations and law firms, including as a partner at the law firms Sidley & Austin and Zelle, Hoffman, Voelbel, Mason and Gette. Ms. Carrig has previously served on the board of directors for a public company and various industry groups and non-profit organizations.

J. Kevin Connaughton – Mr. Connaughton has significant executive and board experience with financial services and investment companies. Mr. Connaughton served as a senior officer of certain Columbia funds from 2003 through 2015. He served as the managing director and general manager of mutual fund products for the Investment Manager from 2010 through 2015. Mr. Connaughton currently serves on the FINRA National Adjudicatory Council and on the Board of Directors of The Autism Project. He has previously served on the Board of Directors of a separate fund group, the Transfer Agent, three offshore groups of funds managed by the Investment Manager and/or affiliates, and the investment committee for a small college endowment. Mr. Connaughton also serves as an adjunct professor of Finance at Bentley University.

Olive Darragh – Ms. Darragh has extensive experience in the investment management industry. She currently serves as Managing Director of Darragh Inc., a strategy and talent management consulting firm that works with investment organizations. Previously, Ms. Darragh was a Partner at Tudor Investments responsible for Strategy and Talent Management. Prior to that, she was a Senior Partner at McKinsey & Company, where she co-founded and led the firm’s global Investment Management practice. Ms. Darragh has experience serving on other boards of directors and is a Certified Public Accountant. Ms. Darragh also founded and runs Zolio Inc., an investment management talent identification platform and is a visiting professor at the University of Edinburgh Business School.

Patricia M. Flynn – Dr. Flynn is a Trustee Professor of Economics and Management at Bentley University, where she previously served as Dean of the McCallum Graduate School of Business. Her research and teaching focus on technology-based economic development, corporate governance and women in business, which she has also written on extensively. She has served on numerous corporate and non-profit boards, including Boston Fed Bancorp Inc., U.S. Trust and The Federal Savings Bank.

Brian J. Gallagher – Mr. Gallagher has 40 years of experience in the financial services industry, including 30 years of service as an audit partner in the financial services practice at Deloitte & Touche LLP. During his tenure at Deloitte, Mr. Gallagher served as the Industry Professional Practice Director for the Investment Management Audit Practice, and oversaw the development of the firm’s audit approach for clients in the industry, consulted on technical issues, and interacted with standard setters and regulators. He also has experience on boards of directors of non-profit organizations.

Douglas A. Hacker – Mr. Hacker has extensive executive experience, having served in various executive roles with United Airlines and more recently as an independent business executive. Mr. Hacker also has experience on other boards of directors. As former chief financial officer of United Airlines, Mr. Hacker has significant experience in accounting and financial management, including in a public company setting.

Nancy T. Lukitsh – Ms. Lukitsh has extensive executive experience in the financial services industries, particularly with respect to the marketing of investment products, having served as Senior Vice President, Partner and Director of Marketing for Wellington Management Company, LLP. Ms. Lukitsh has previously served as Chair of Wellington Management Portfolios (commingled investment pools designed for non-U.S. institutional investors) and as a director of other Wellington affiliates. In addition, she has previously served on the boards of directors of various non-profit organizations. She is also a Chartered Financial Analyst.

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David M. Moffett – Mr. Moffett has extensive executive and board of director experience, including serving on audit committees for public companies. Mr. Moffett was selected as CEO when the Federal Home Loan Mortgage Corporation was placed under conservatorship in 2008, and served as a consultant to its interim chief executive officer and the board of directors until 2009. Formerly, Mr. Moffett was the CFO of a large U.S. bank holding company where his responsibilities included trust and wealth management.

Catherine James Paglia – Ms. Paglia has been a Director of Enterprise Asset Management, Inc., a real estate and asset management company, for over 15 years. She previously spent eight years as a Managing Director at Morgan Stanley, 10 years as a Managing Director of Interlaken Capital and served as Chief Financial Officer of two public companies. She also has experience on other boards of directors of public and non-profit organizations.

Christopher O. Petersen – Mr. Petersen has significant experience with the financial services and investment companies. Mr. Petersen has served as President of the Columbia Funds since 2015 and as an officer of the Columbia Funds and affiliated funds since 2007. He serves as Vice President and Lead Chief Counsel of Ameriprise Financial, Inc., the parent company of the Investment Manager. In these capacities, he supports the management of the business and legal affairs of the Columbia Funds.

Anthony M. Santomero – Dr. Santomero is the former President of the Federal Reserve Bank of Philadelphia. He holds the title of Richard K. Mellon Professor Emeritus of Finance at the Wharton School of the University of Pennsylvania and serves on the board of a public company, RenaissanceRe Holdings Ltd., and the board of Penn Mutual Life Insurance Company. He previously served as director of Citigroup Inc. and Citibank, N.A., Senior Advisor at McKinsey & Company and was the Richard K. Mellon Professor of Finance at the University of Pennsylvania’s Wharton School. During his 30-year tenure at Wharton, he held a number of academic and managerial positions, including Deputy Dean of the School. He has written approximately 150 articles, books and monographs on financial sector regulation and economic performance.

Minor M. Shaw – Ms. Shaw is President of Micco, LLC, a private investment company, and past president of Micco Corporation and Mickel Investment Group. She is chairman of the Daniel-Mickel Foundation and The Duke Endowment. She also currently serves as chairman of the Greenville-Spartanburg Airport Commission. She holds numerous civic and business board memberships and is a past chair of Wofford College Board of Trustees. Ms. Shaw serves on the board of the Hollingsworth Funds (formerly Board Chair of the Hollingsworth Funds), Blue Cross Blue Shield of South Carolina, and on the advisory board of Duke Energy Corp. She has also served on the boards of Citizens & Southern Bank of SC, Interstate Johnson Lane, and Piedmont Natural Gas.

Natalie A. Trunow – Ms. Trunow has extensive executive experience in financial services and with investment companies, including service as Chief Executive Officer at Millennial Portfolio Solutions LLC (asset management and consulting services), as a non-executive member of the Investment Committee of Sarona Asset Management Inc. (a private equity firm), as Director of Investments at Casey Family Programs Foundation, as Senior Vice President and Chief Investment Officer at Calvert Investments, and as Section Head and Portfolio Manager responsible for alternative and traditional funds at General Motors Asset Management. Ms. Trunow’s responsibilities as Senior Vice President and Chief Investment officer at Calvert Investments included oversight responsibilities for public and private equity investments, in-house and sub-advised funds, asset allocation funds, balanced funds, and volatility-managed funds, and investing portfolios. Ms. Trunow also currently serves on the boards of for-profit and non-profit organizations.

Sandra Yeager – Ms. Yeager has over 26 years of experience in the financial services industry. In August of 2008 she founded Hanoverian Capital, LLC, an investment boutique specializing in international equities for institutional clients, where she served as President and Chief Investment Officer through December 2016. Prior to that, Ms. Yeager served as Head of International Equities for DuPont Capital and Head of Global Equity Research for Morgan Stanley Investment Management, where she led a team of thirty people. Ms. Yeager began her investment career at AllianceBernstein as an equity analyst and advanced to become a global portfolio manager for institutional and mutual fund clients.

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Responsibilities of the Boards with Respect to Fund Management

The Boards consist of Trustees who have varied experience and skills. Each Board is chaired by an Independent Trustee who has significant additional responsibilities compared to the other Trustees, including, among other things: overseeing the setting of the agenda for Board meetings, communicating and meeting with Board members between Board and committee meetings on Fund-related matters, with the Funds’ Chief Compliance Officer, counsel to the Independent Trustees, and representatives of the Funds’ service providers. Each Board reviews its leadership structure periodically and believes that its structure is appropriate, in light of the size of the applicable Trust and the nature of its business, to enable the Board to exercise its oversight of the Funds and the other investment companies overseen by the Trustees. In particular, the Boards believe that having an Independent Trustee serve as the chair of the Board and having other Independent Trustees serve as chairs of each committee promotes independence from the Investment Manager in overseeing the setting of agendas and conducting meetings. With respect to Messrs. Truscott and Petersen, the Trustees have concluded that having a senior officer of the Investment Manager serve as a Trustee benefits Fund shareholders by facilitating communication between the Independent Trustees and the senior management of the Investment Manager, and by assisting efforts to align the interests of the Investment Manager more closely with those of Fund shareholders. Further information about the backgrounds and qualifications of the Nominees can be found in the section entitled “Nominee Qualifications” above. The Boards have several standing committees (each, a “Committee”), which are an integral part of each Fund’s overall governance and risk oversight structure. The Boards believe that their Committee structure makes the oversight process more efficient and more effective by allowing, among other things, smaller groups of Trustees to bring increased focus to matters within the purview of each Committee. The roles of each Committee are more fully described in the section entitled “Governance Structure and Committees of the Boards” below.

The Boards initially approved investment management services agreements and other contracts with the Investment Manager and its affiliates and other service providers. The Boards monitor the level and quality of services provided under such contracts. Annually, the Boards evaluate the services received under the investment management and distribution contracts by reviewing, among other things, reports covering investment performance, expenses, shareholder services, marketing, and the Investment Manager’s profitability.

The Investment Manager provides the Funds with investment advisory services, and is responsible for day-to-day administration of the Funds and management of the risks that arise from the Funds’ investments and operations. The Boards provide oversight of the services provided by the Investment Manager, including risk management services. Various Committees of the Boards provide oversight of the Investment Manager’s risk management services with respect to the particular activities within the Committee’s purview. In the course of providing oversight, the Boards and the Committees receive a wide range of reports with respect to the Funds’ activities, including reports regarding each Fund’s investment portfolio, the compliance of the Funds with applicable laws, and the Funds’ financial accounting and reporting. The Boards and the relevant Committees meet periodically with officers of the Funds and the Investment Manager and with representatives of various Fund service providers. In addition, the Boards oversee processes that are in place addressing compliance with applicable rules, regulations and investment policies and address possible conflicts of interest. The Boards and certain Committees also meet regularly with the Funds’ Chief Compliance Officer to receive reports regarding the compliance of the Funds and the Investment Manager with the federal securities laws and their internal compliance policies and procedures. In addition, the Boards meet periodically with the portfolio managers of the Funds to receive reports regarding the management of the Funds.

The Boards also oversee the Funds’ liquidity risk through, among other things, receiving periodic reporting and presentations by investment and other personnel of the Investment Manager. Additionally, as required by Rule 22e-4 under the 1940 Act, the Funds have implemented a written liquidity risk management program and related procedures (the “Liquidity Program”), designed to assess and manage the Funds’ liquidity risk. The Boards, including a majority of the Independent Trustees, approved the designation of a liquidity risk management program administrator (the “Liquidity Program Administrator”) who is responsible for

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administering the Liquidity Program. The Boards will review, no less frequently than annually, a written report prepared by the Liquidity Program Administrator that addresses the operation of the Liquidity Program and assesses its adequacy and effectiveness of implementation.

The Boards recognize that not all risks that may affect the Funds can be identified in advance; that it may not be practical or cost-effective to eliminate or mitigate certain risks; that it may be necessary to bear certain risks (such as various investment-related risks) in seeking to achieve the Funds’ investment objectives; and that the processes and controls employed to address certain risks may be limited in their effectiveness. As a result of the foregoing and other factors, the Boards’ risk management oversight is subject to substantial limitations.

Governance Structure and Committees of the Boards

If the consolidation of the two Boards is completed, it is anticipated that the combined board will have a Committee structure similar to both Boards, but more closely aligned with the current Committee structure of the Columbia Funds Board. Nevertheless, the combined board may choose to modify the governance structure of the combined board at any time. Information relating to the current governance and Committee structure of the Columbia Atlantic Board and Columbia Funds Board is set forth below.

Columbia Atlantic Board

The Columbia Atlantic Board has organized the following standing Committees to facilitate its work: the Audit Committee, the Governance Committee, the Advisory Fees & Expenses Committee, the Compliance Committee, the Investment Oversight Committees and the Product and Distribution Committee. These Committees are comprised solely of Independent Trustees. The table above providing background on each Trustee also includes their respective Committee assignments. The duties of these Committees are described below.

Governance Committee. The Governance Committee’s functions include recommending to the Board nominees for Independent Trustee positions and for appointments to various Committees, overseeing the Board’s periodic evaluations of the effectiveness of the Board, reviewing and recommending to the Board governance and other policies and practices to be followed in carrying out the Trustees’ duties and responsibilities, and reviewing and making recommendations to the Board regarding the compensation of the Independent Trustees.

The Governance Committee will consider nominees for trustee recommended by shareholders provided that, as applicable, such recommendations are submitted by the date disclosed in a Fund’s proxy statement soliciting proxies to be voted at a meeting of shareholders, if such a meeting is held (mutual funds and exchange-traded funds are not required to hold annual shareholder meetings) and otherwise comply with applicable securities laws, including Rule 14a-8 under the Securities Exchange Act of 1934, as amended. Such shareholder recommendations must be in writing and should be sent to the attention of Douglas A. Hacker, Chair of the Board, Columbia Funds Complex, 225 Franklin Street, Mail Drop BX32 05228, Boston, MA 02110. Shareholder recommendations should include the proposed nominee’s biographical information (including business experience for the past ten years) and a description of the qualifications of the proposed nominee, along with a statement from the proposed nominee that he or she is willing to serve and meets the requirements to serve as an Independent Trustee, if applicable. All satisfactorily completed information packages regarding a candidate will be forwarded to a member of the Governance Committee for consideration. Recommendations for candidates will be evaluated in light of whether the number of Trustees of the Trust is expected to be increased and anticipated vacancies. All nominations from Fund shareholders will be considered. There may be times when the Governance Committee is not recruiting new trustees. In that case, shareholder recommendations will be maintained on file pending the active recruitment of trustees.

When considering candidates for trustee, the Governance Committee considers, among other things, whether prospective nominees have distinguished records in their primary careers, personal and professional

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integrity, and substantive knowledge in areas important to the Board’s operations, such as background or education in finance, auditing, securities law, the workings of the securities markets or investment advice. For candidates to serve as Independent Trustees, independence from the Funds’ investment adviser, its affiliates and other principal service providers is critical, as is an independent and questioning mindset. In each case, the Governance Committee will evaluate whether a candidate is an “interested person” under the 1940 Act. The Governance Committee also considers whether a prospective candidate’s workload would be consistent with regular attendance at Board meetings and would allow him or her to be available for service on Board Committees, and devote the additional time and effort necessary to stay apprised of Board matters and the rapidly changing regulatory environment in which the Funds operate. Different substantive areas may assume greater or lesser significance at particular times, in light of a Board’s present composition and its perceptions about future issues and needs.

The Governance Committee may use any process it deems appropriate for identifying and evaluating candidates for service as a Trustee, which may include, without limitation, personal interviews, background checks, written submissions by the candidates, third party references and the use of consultants, including professional recruiting firms. The Governance Committee will evaluate nominees for a particular vacancy using the same process regardless of whether the nominee is submitted by a shareholder or identified by some other means. On an annual basis, the Board conducts a self-evaluation that considers, among other matters, the contributions of individual Trustees, whether the Board has an appropriate size and the right mix of characteristics, experiences and skills, and whether the age distribution and diversity among the Trustees is appropriate. The Board and the Governance Committee also consider the same factors when identifying prospective trustee candidates.

The Governance Committee initially evaluates prospective candidates on the basis of their resumes, considered in light of the criteria discussed above. Those prospective candidates that appear likely to be able to fill a significant need of the Board would be contacted by a Governance Committee member by telephone to discuss the position; if there appeared to be sufficient interest, an in-person meeting with one or more of the Governance Committee members would be arranged. If a Governance Committee member, based on the results of these contacts, believes he or she has identified a viable candidate, he or she would air the matter with the other Governance Committee members for input. Any request by Fund management to meet with the prospective candidate would be given appropriate consideration. To assist with the identification and vetting of potential trustee nominees, the Governance Committee has engaged the services of third party recruiting firms.

The Governance Committee has a charter, which is provided in Appendix E-1. The Governance Committee’s charter is not available on the Funds’ website. The number of Governance Committee meetings of each Fund held during its last fiscal year is shown in Appendix F.

Compliance Committee. The Compliance Committee’s functions include, among other things, monitoring, supervising and assessing the performance of the Funds’ Chief Compliance Officer and reviewing his compensation, reviewing periodically and recommending changes to the codes of ethics and compliance policies of the Funds and its service providers, and reviewing each Fund’s portfolio execution. The number of Compliance Committee meetings of each Fund held during its last fiscal year is shown in Appendix F.

Advisory Fees & Expenses Committee. The Advisory Fees & Expenses Committee’s functions include reviewing and making recommendations to the Board as to contracts requiring approval of a majority of the Independent Trustees and as to any other contracts or fee proposals that may be referred to the Advisory Fees & Expenses Committee by the Board. The number of Advisory Fees & Expenses Committee meetings of each Fund held during its last fiscal year is shown in Appendix F.

Investment Oversight Committee. Each Independent Trustee also serves on an Investment Oversight Committee (each, an “IOC”). Each IOC is responsible for monitoring, on an ongoing basis, a select group of Columbia Funds overseen by the Board and gives particular consideration to such matters as each Fund’s

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adherence to its investment mandates, historical performance, changes in investment processes and personnel, and proposed changes to investment objectives. Investment personnel who manage the Funds attend IOC meetings from time to time to assist each IOC in its review of the Funds. The number of IOC meetings of each Fund held during its last fiscal year is shown in Appendix F.

Audit Committee. The Audit Committee’s functions include making recommendations to the Board regarding the selection and performance of the independent registered public accounting firm, and reviewing matters relating to accounting and auditing practices and procedures, accounting records and the internal accounting controls of the Funds and certain service providers. The Audit Committee reviews Fund valuation matters as it deems appropriate and consistent with the Columbia Atlantic Board’s responsibilities in this regard. The Audit Committee is comprised entirely of Independent Trustees. The Board has adopted a written charter for the Audit Committee. The number of Audit Committee meetings of each Fund held during its last fiscal year is shown in Appendix F.

Product and Distribution Committee. The Product and Distribution Committee’s functions include, among other things, reviewing such matters relating to the marketing of the Funds and the distribution of the Fund’s shares, including matters relating to the design and positioning of Funds, marketing and distribution strategies for the Funds and the effectiveness and competitiveness of such strategies, as the Product and Distribution Committee may deem appropriate. The number of Product and Distribution Committee meetings of each Fund held during its last fiscal year is shown in Appendix F.

Columbia Funds Board

The Columbia Funds Board has organized the following standing Committees to facilitate its work: Board Governance Committee, Compliance Committee, Contracts Committee, Executive Committee, Investment Review Committee and Audit Committee. These Committees are comprised solely of Independent Trustees. The table above providing background on each Trustee also includes their respective Committee assignments. The duties of these Committees are described below.

Board Governance Committee. Recommends to the Board the size, structure and composition of the Board and its Committees; the compensation to be paid to members of the Board; and a process for evaluating the Board’s performance. The Board Governance Committee also reviews candidates for Board membership, including candidates recommended by shareholders. The Board Governance Committee also makes recommendations to the Board regarding responsibilities and duties of the Board, oversees proxy voting and supports the work of the Board Chair in relation to furthering the interests of the Funds and other funds in the Columbia Funds Complex overseen by the Board and their shareholders.

To be considered as a candidate for trustee, recommendations must include a curriculum vitae and be mailed to Catherine James Paglia, Chair of the Board, Columbia Funds Complex, 225 Franklin Street, Mail Drop BX32 05228, Boston, MA 02110. To be timely for consideration by the Board Governance Committee, the submission, including all required information, must be submitted in writing by the date disclosed in a Fund’s proxy statement soliciting proxies to be voted at a meeting of shareholders, if such a meeting is held (mutual funds, including exchange-traded funds, are not required to hold annual shareholder meetings). The Board Governance Committee will consider only one candidate submitted by such a shareholder or group for nomination for election at a meeting of shareholders. The Board Governance Committee will not consider self-nominated candidates or candidates nominated by members of a candidate’s family, including such candidate’s spouse, children, parents, uncles, aunts, grandparents, nieces and nephews.

The Board Governance Committee will consider and evaluate candidates submitted by the nominating shareholder or group on the basis of the same criteria as those used to consider and evaluate candidates submitted from other sources. The Board Governance Committee may take into account a wide variety of factors in considering trustee candidates, including (but not limited to): (i) the candidate’s knowledge in matters relating to

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the investment company industry; (ii) any experience possessed by the candidate as a director or senior officer of other public or private companies; (iii) the candidate’s educational background; (iv) the candidate’s reputation for high ethical standards and personal and professional integrity; (v) any specific financial, technical or other expertise possessed by the candidate, and the extent to which such expertise would complement the Board’s existing mix of skills and qualifications; (vi) the candidate’s perceived ability to contribute to the ongoing functions of the Board, including the candidate’s ability and commitment to attend meetings regularly, work collaboratively with other members of the Board and carry out his or her duties in the best interests of the Funds; (vii) the candidate’s ability to qualify as an independent trustee; and (viii) such other criteria as the Board Governance Committee determines to be relevant in light of the existing composition of the Board and any anticipated vacancies or other factors.

Members of the Board Governance Committee (and/or the Board) also meet personally with each nominee to evaluate the candidate’s ability to work effectively with other members of the Board, while also exercising independent judgment. Although the Board does not have a formal diversity policy, the Board endeavors to comprise itself of members with a broad mix of professional and personal backgrounds. Thus, the Board Governance Committee and the Board accorded particular weight to the individual professional background of each Independent Trustee.

The Board Governance Committee has a charter, which is provided in Appendix E-2. The Board Governance Committee’s charter is not available on the Funds’ website. The number of Board Governance Committee meetings of each Fund held during its last fiscal year is shown in Appendix F.

Compliance Committee. Supports the Funds’ maintenance of a strong compliance program by providing a forum for Independent Trustees to consider compliance matters impacting the Funds or their key service providers; developing and implementing, in coordination with the Chief Compliance Officer, a process for the review and consideration of compliance reports that are provided to the Board; and providing a designated forum for the Funds’ Chief Compliance Officer to meet with Independent Trustees on a regular basis to discuss compliance matters. The number of Compliance Committee meetings of each Fund held during its last fiscal year is shown in Appendix F.

Contracts Committee. Reviews and oversees the contractual relationships with service providers. Receives and analyzes reports covering the level and quality of services provided under contracts with the Funds and advises the Board regarding actions taken on these contracts during the annual review process. Reviews and considers, on behalf of all Trustees, the Funds’ investment advisory, subadvisory (if any), administrative services and principal underwriting contracts to assist the Trustees in fulfilling their responsibilities relating to the Board’s evaluation and consideration of these arrangements. The number of Contracts Committee meetings of each Fund held during its last fiscal year is shown in Appendix F.

Executive Committee. Acts, as needed, for the Board between meetings of the Board, and can meet in advance of, and/or for planning, regularly scheduled meetings or other Board matters. The number of Executive Committee meetings of each Fund held during its last fiscal year is shown in Appendix F.    The Executive Committee ceased to operate as of June 2020 and will not be in operation for the combined board.

Investment Review Committee. Reviews and oversees the management of the Funds’ assets. Considers investment management policies and strategies; investment performance; risk management techniques; and securities trading practices and reports areas of concern to the Board. The number of Investment Review Committee meetings of each Fund held during its last fiscal year is shown in Appendix F.

Audit Committee. Oversees the accounting and financial reporting processes of the Funds and internal controls over financial reporting. Oversees the quality and integrity of the Funds’ financial statements and independent audits as well as the Funds’ compliance with legal and regulatory requirements relating to the Funds’ accounting and financial reporting, internal controls over financial reporting and independent audits. The

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Audit Committee also makes recommendations regarding the selection of the Funds’ independent registered public accounting firm (i.e., independent auditors) and reviews and evaluates the qualifications, independence and performance of the auditor. The Audit Committee oversees the Funds’ risks by, among other things, meeting with the Funds’ internal auditors, establishing procedures for the confidential, anonymous submission by employees of concerns about accounting or audit matters, and overseeing the Funds’ Disclosure Controls and Procedures. The Audit Committee acts as a liaison between the independent auditors and the full Board and must prepare an Audit Committee report. The Audit Committee reviews Fund valuation matters as it deems appropriate and consistent with the Columbia Funds Board’s responsibilities in this regard. The number of Audit Committee meetings of each Fund held during its last fiscal year is shown in Appendix F.

Trustee Meeting Attendance

The number of Board meetings of each Fund held during its last fiscal year is shown in Appendix F. During the last fiscal year, each Trustee attended 75% or more of the meetings of the Board on which the Trustee serves and the Committee meetings (if a member thereof) held during the period. The Trusts do not have a formal policy on Trustee attendance at Board and Committee meetings. The Trusts do not hold annual shareholder meetings and therefore the Boards do not have a policy with regard to Trustee attendance at such meetings.

Beneficial Ownership of Shares of Each Fund

Appendix G to this Joint Proxy Statement provides information, as of September 30, 2020, about the beneficial ownership by the Nominees of equity securities of each Fund.

Independent Trustee Interests in Fund Affiliates

An immediate family member of Ms. Blatz holds publicly traded common stock of the parent companies of the sub-advisers to certain Funds. The value of such stock does not exceed $120,000 with respect to the parent company of any sub-adviser other than JPMorgan and Morgan Stanley, and the value of the holdings of each such sub-adviser parent does not exceed $500,000 and represents less than 0.1 percent of the parent’s outstanding shares. Ms. Blatz does not have any ownership or voting interest in such holdings.

Remuneration for Trustees and Officers

Total fees paid by each Fund to the Independent Trustees for the Fund’s last fiscal year are set forth in Appendix H to this Joint Proxy Statement. If all of the Nominees are elected by shareholders of the Trusts, it is expected that the combined Board will reconsider its compensation structure such that the Independent Trustees will be compensated under a new, unified compensation structure. Persons who are employees, officers or directors of Columbia Threadneedle receive no remuneration for serving as Trustees. No Trustee or Nominee, other than Messrs. Truscott and Petersen, is an employee of Columbia Threadneedle or its affiliates.

Under the terms of the Deferred Fee Agreement (the “Deferred Compensation Plan”) applicable to each Board, each eligible Independent Trustee may elect, on an annual basis, to defer receipt of all or a portion of compensation payable to him or her for service as an Independent Trustee for that calendar year (expressly, an Independent Trustee may elect to defer his/her annual retainer, his/her attendance fees, or both components, which together comprise total compensation for service). Fees deferred by an Independent Trustee are credited to a book reserve account (the “Deferral Account”) established by the Columbia Funds, the value of which is derived from the rate of return of one or more Columbia Funds selected by the Independent Trustee (with accruals to the Deferral Account beginning at such time as an Independent Trustee’s fund elections having been established, and proceeds for service having been paid into such account, and terminating at such time as when proceeds become payable to such Independent Trustee under the Deferred Compensation Plan). Independent Trustees may change their fund elections only in accordance with the provisions of the Deferred Compensation Plan.

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Distributions from an Independent Trustee’s Deferral Account will be paid by check, either in a lump sum or in annual installments. Payments made in annual installments are disbursed over a period of up to ten years, following such time as an Independent Trustee may qualify to receive such payments. If a deferring Independent Trustee dies prior to or after the commencement of the disbursement of amounts accrued in his/her Deferral Account, the balance of the account will be distributed to his/her designated beneficiary either in lump sum or in annual payments as established by such Independent Trustee himself/herself, his/her beneficiary or his/her estate. Amounts payable under the Deferred Compensation Plan are not funded or secured in any way, and each deferring Independent Trustee has the status of a general unsecured creditor of the Columbia Fund(s) from which compensation has been deferred.

Columbia Threadneedle or its affiliates pay all salaries of officers of the Trusts, except for the Funds’ Chief Compliance Officer, a portion of whose compensation is paid by the Trusts.

The Columbia Funds Board has adopted a trustee investment policy, pursuant to which each Independent Trustee shall, within three years of becoming an Independent Trustee, invest in shares (including investments made pursuant to the Deferred Compensation Plan) of one or more funds overseen by the Columbia Funds Board (including the closed-end funds overseen by the Columbia Funds Board) in an aggregate amount that is at least equal to the minimum investment amount as determined by the Columbia Funds Board. The minimum investment amount is generally based on the total annual compensation paid to an Independent Trustee (exclusive of any compensation paid to an Independent Trustee for serving as Chair of the Columbia Funds Board or a Committee of the Columbia Funds Board or in any other special capacity) and may be adjusted by the Columbia Funds Board from time-to-time. Each Independent Trustee on the Columbia Funds Board is expected to maintain the minimum investment amount during his or her tenure as an Independent Trustee. The Columbia Atlantic Board has a substantially similar expectation, but not requirement, for its Independent Trustees to invest in shares (including investments made pursuant to the Deferred Compensation Plan) of one or more funds overseen by the Columbia Atlantic Board.

Executive Officers of the Funds

Information about the executive officers of the Trusts is included in Appendix I to this Joint Proxy Statement.

Independent Registered Public Accounting Firm

Each Board, including the Independent Trustees, has selected PricewaterhouseCoopers LLP (“PwC”), 45 South Seventh Street, Suite 3400, Minneapolis, MN 55402, to act as the independent registered public accounting firm to audit the books and records of each Fund for its respective fiscal year. A representative of PwC is expected to be present at the Meeting and, if present, will be available to respond to any appropriate questions raised at the Meeting and may make a statement.

Additional information regarding fees paid during the previous two fiscal years to PwC and the Audit Committee pre-approval policies and procedures is contained in Appendix J.

Required Vote and Recommendation

Election of Nominees requires the vote of a plurality of the votes cast at the Meeting by or on behalf of shareholders of each Trust, at which a quorum is present or represented by proxy.

THE BOARD OF EACH TRUST UNANIMOUSLY RECOMMENDS THAT SHAREHOLDERS

VOTE FOR THE ELECTION OF ALL NOMINEES OF ITS TRUST

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PROXY VOTING AND SHAREHOLDER MEETING INFORMATION

Proxy Solicitation

Shareholders or the persons named as their proxies may cast votes in their discretion on any other matter that may properly come before the Meeting, including, but not limited to, proposing and/or voting on the adjournment and/or postponement of the Meeting with respect to the proposal in the event that a quorum is not obtained and/or sufficient votes in favor of the proposal are not received.

If you properly authorize your proxy through the Internet or telephonically, or by executing and returning the enclosed Proxy Card, and your proxy is not subsequently revoked, your votes will be cast at the Meeting. If you return your signed Proxy Card without instructions, your votes will be cast FOR the election of the Nominees. Your votes will be cast in the discretion of the proxy holders on any other matter that may properly come before the Meeting, including, but not limited to, proposing and/or voting on the adjournment and/or postponement of the Meeting with respect to the proposal in the event that a quorum is not obtained and/or sufficient votes in favor of the proposal are not received.

Revocation of Proxies

If you execute and submit a proxy, you may revoke that proxy or change it by written notice to the Funds’ proxy solicitor at Computershare Fund Services, c/o Operations Department, 2950 Express Drive South, Suite 210, Islandia, New York 11749, by submitting a subsequently executed and dated Proxy Card, by authorizing your proxy by telephone or Internet, or by attending the Meeting and casting your vote in person (virtually), or as otherwise permitted. Attending the Meeting will not automatically revoke your prior proxy.

Quorum and Methods of Tabulation

A quorum is required to take action on the proposal. For CFST II, ten percent (10%) of the votes entitled to be cast at the Meeting, present at the Meeting in person (virtually) or by proxy, constitutes a quorum. For each of CETF I and CFST I, thirty percent (30%) of the votes entitled to be cast at the Meeting, present at the Meeting in person (virtually) or by proxy, constitutes a quorum. For CFST, thirty-three and one-third percent (33 1/3%) of the shares entitled to vote at the Meeting, present at the Meeting in person (virtually) or by proxy, constitutes a quorum. For CETF II, forty percent (40%) of the outstanding shares entitled to vote at the Meeting, present at the Meeting in person (virtually) or by proxy, constitutes a quorum. Abstentions and “broker non-votes” (i.e., shares held of record by a financial intermediary, such as a broker, or nominee, typically in “street name,” as to which proxies have been returned but (i) instructions have not been received from the beneficial owners or persons entitled to vote and (ii) the broker or nominee does not have discretionary voting power on a particular matter) will be treated as present for purposes of determining a quorum but will not be considered a vote cast. Abstentions and broker non-votes will have no effect with respect to the election of the Nominees. The Funds do not currently expect any broker non-votes because the proposal being considered is a routine matter.

Shareholders of record of each Fund at the close of business on the applicable Record Date are entitled to notice of, and to vote at, the Meeting. As previously indicated, the number of outstanding shares of each class of shares of each Fund held on the applicable Record Date is listed in Appendix A. With respect to CFST I, CETF I and CFST II, shareholders of the Funds are entitled to one vote for each dollar of net asset value (number of shares owned times net asset value per share) determined at the close of business on the applicable Record Date and each fractional share is entitled to a proportionate fractional vote. With respect to CETF II and CFST, shareholders of the Funds are entitled to one vote for each whole share determined at the close of business on the applicable Record Date and each fractional share is entitled to a proportionate fractional vote. Appendix B to this Joint Proxy Statement lists the persons that, to the knowledge of the Funds, owned beneficially 5% or more of the outstanding shares of any class of each Fund as of the applicable Record Date.

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If your shares are held in an IRA, you have the right to vote those shares. If you do not provide voting instructions with respect to your shares, your IRA custodian may or may not, depending upon the terms of your IRA agreement, vote shares for which it has not received your voting instructions. Please consult your IRA agreement and/or financial advisor for more information.

Adjournment

In the event that a quorum of shareholders of a Fund is not present at the Meeting, the Meeting may be adjourned by the vote of a majority of the shares represented at the Meeting, either in person (virtually) or by proxy, and further solicitations may be made.

Required Vote

All shares of each Trust vote together as a single class on the proposal. For each Trust, the election of trustees requires the affirmative vote of a plurality of votes cast at the Meeting by or on behalf of shareholders of the Trust. A “plurality of votes cast” means that a nominee is elected if he or she receives the highest number of affirmative votes cast, whether or not such votes constitute a majority of outstanding voting shares, up to the maximum number of trustees to be elected at the Meeting, which is seventeen (17). Because the Nominees are running unopposed, all seventeen (17) Nominees are expected to be elected as trustees, as all Nominees who receive votes in favor will be elected, while votes not cast or votes to withhold will have no effect on the election outcome. If approved, the proposal will become effective on January 1, 2021.

Other funds managed by Columbia Threadneedle or its affiliates (such funds, the “Columbia Funds”) hold a significant percentage of the outstanding voting shares of certain Funds. As of the applicable Record Date, other Columbia Funds or affiliates held a significant percentage of outstanding shares of CETF I and CFST II. These other Columbia Funds are expected to vote their Fund shares in the same proportion as the shares voted by the other shareholders, although they may vote all their shares for or against the Nominees if their respective Board so determines.

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OTHER INFORMATION

Current Service Providers

Columbia Threadneedle, located at 225 Franklin Street, Boston, Massachusetts 02110, serves as the investment manager of each Fund, and the other Columbia Funds that invest in the Funds (if applicable). Columbia Management Investment Distributors, Inc., also located at 225 Franklin Street, Boston, Massachusetts 02110, serves as the principal underwriter of each Fund and the investing Columbia Funds (if applicable). Columbia Threadneedle and Columbia Management Investment Distributors, Inc. are subsidiaries of Ameriprise Financial, Inc.

Other Matters to Come Before the Meeting

Fund management does not know of any matters to be presented at the Meeting other than those described in this Joint Proxy Statement. If other business should properly come before the Meeting, the persons named as proxies will vote thereon in accordance with their best judgment.

Procedures for Communications to the Board

Shareholders who want to communicate with each Board or an individual Trustee must send written communications to the applicable Trust, c/o the Secretary, 225 Franklin Street, Boston, Massachusetts 02110, addressed to the Board of Trustees of the Fund or the individual Trustee. The Secretary may determine not to forward to the Board any letter that does not relate to the business of a Fund.

Proposals of Shareholders

The Trusts do not generally hold annual shareholders’ meetings, but will hold special meetings as required or deemed desirable by the relevant Board. Because the Trusts do not hold regular shareholders’ meetings, the anticipated date of the next shareholders’ meeting (if any) cannot be provided. Shareholders wishing to submit proposals for inclusion in a proxy statement for a subsequent shareholders’ meeting of the applicable Trust, including submitting nominees for election as trustees, should send their written proposals to the applicable Trust (c/o the Secretary), 225 Franklin Street, Boston, Massachusetts 02110. Proposals must be received in a reasonable time before a Trust begins to print and mail the proxy materials for a shareholders’ meeting. The timely submission of a proposal does not guarantee its inclusion.

Principal Shareholders

Appendix B to this Joint Proxy Statement lists the persons that, to the knowledge of the Funds, owned beneficially 5% or more of the outstanding shares of any class of each Fund as of the applicable Record Date. A shareholder who owns beneficially, directly or indirectly, more than 25% of a Fund’s voting securities is presumed to be a “control person” (as defined in the 1940 Act) of the Fund. Columbia Funds managed by Columbia Threadneedle may be presumed under securities laws to control a Fund and may be able to determine the outcome of issues that are submitted to shareholders for vote. As of September 30, 2020, the Trustees and Officers of CETF I, CETF II and CFST, as a group, beneficially owned less than 1% of each class of shares of each Fund that is a series of CETF I, CETF II and CFST.

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As of September 30, 2020, the Trustees and Officers of CFST I, as a group, beneficially owned less than 1% of each class of shares of each Fund that is a series of CFST I, except as set forth in the table below:

As of September 30, 2020, the Trustees and Officers of CFST II, as a group, beneficially owned less than 1% of each class of shares of each Fund that is a series of CFST II, except as set forth in the table below:

Expenses and Solicitation Activities

The Funds and Columbia Threadneedle will jointly bear the expenses incurred in connection with the solicitation of proxies for the Meeting with regard to the election of trustees. Columbia Threadneedle has agreed to bear approximately 42% of each Fund’s cost, and also to bear any Fund’s remaining costs to the extent such remaining costs exceed 0.0049% of that Fund’s net assets, except that Columbia Threadneedle will bear 100% of these expenses for Columbia Large Cap Index Fund, Columbia Small Cap Index Fund, Columbia U.S. Treasury Index Fund and each series of CETF I and CETF II as a result of these Funds’ unitary fee arrangements. The expenses incurred in connection with the solicitation of proxies for the Meeting include preparation, filing, printing, mailing and solicitation expenses and expenses of any proxy solicitation firm, pro rata based on the number of shareholder accounts for printing and mailing costs and allocated equally among all Funds for preparation and filing costs. These expenses are estimated to be approximately $5,900,000.

In addition to the use of the mail, proxies may be solicited personally or via facsimile, telephone or the Internet by trustees, officers and employees of the Trusts, Columbia Threadneedle, Columbia Management Investment Distributors, Inc. and the Funds’ transfer agent, Columbia Management Investment Services Corp. Computershare Fund Services will provide shareholder meeting services and assist in soliciting and tracking votes. The cost for such services is currently estimated to be approximately $4,800,000 (which is reflected in the overall expenses noted in the preceding paragraph). The agreement with Computershare provides for indemnification of Computershare in certain circumstances, includes typical representations and warranties, sets forth service level standards and requires Computershare to keep certain information confidential.

Fiscal Year

In connection with information provided in this Joint Proxy Statement, Appendix C lists the fiscal year-end for each Fund.

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Proxy Statement Delivery

“Householding” is the term used to describe the practice of delivering one copy of a document to a household of shareholders instead of delivering one copy of a document to each shareholder in the household. Shareholders of each Fund who share a common address and who have not opted out of the householding process should receive a single copy of the Joint Proxy Statement together with one Proxy Card or the Notice of Internet Availability of Proxy Materials for each account. If you received more than one copy of the Joint Proxy Statement or the Notice of Internet Availability of Proxy Materials, you may elect to household in the future; if you received a single copy of the Joint Proxy Statement or the Notice of Internet Availability of Proxy Materials, you may opt out of householding in the future; and you may, in any event, obtain an additional copy of this Joint Proxy Statement by calling 800-708-7953 or writing to the relevant Fund at the following address: 225 Franklin Street, Boston, Massachusetts 02110, Attention: Secretary. Copies of this Joint Proxy Statement and the accompanying Notice of Joint Special Meeting are also available at https://www.proxy-direct.com/col-31702.

Shareholder Reports

Each Fund’s most recent semiannual and annual reports previously have been delivered to shareholders. Each Fund will furnish, without charge, a copy of its most recent annual shareholder report and semi-annual shareholder report on request. Additional copies of any of these documents are available by writing to Columbia Funds, c/o Columbia Management Investment Services Corp., P.O. Box 219104, Kansas City, MO 64121-9104 or by calling (800) 345-6611. All of these documents also are filed with the SEC and are available on the SEC’s website at www.sec.gov.

PROMPT EXECUTION AND RETURN OF THE ENCLOSED PROXY CARD IS REQUESTED. A PRE-ADDRESSED, POSTAGE-PAID ENVELOPE IS ENCLOSED FOR YOUR CONVENIENCE, AND TELEPHONE AND INTERNET VOTING IS AVAILABLE.

By order of each Board of Trustees,

Ryan C. Larrenaga,

Secretary

It is important that you authorize proxies promptly. All shareholders, including those who expect to attend the Meeting virtually, are urged to authorize their proxy as soon as possible by accessing the Internet site listed on the enclosed Proxy Card, by calling the toll-free number listed on the enclosed Proxy Card, or by mailing the enclosed Proxy Card in the enclosed return envelope, which requires no postage if mailed in the United States. To enter the Meeting, you will need proof of ownership of the shares of the relevant Fund, such as your Proxy Card (or a copy thereof) or, if your shares are held of record by a financial intermediary, such as a broker, or nominee, a Proxy Card from the record holder or other proof of beneficial ownership, such as a brokerage statement showing your holdings of the shares of the Fund.

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APPENDIX A — SHARES OUTSTANDING

The table below shows the number of shares outstanding for each Fund that is a series of CFST, CFST I and CFST II as of October 9, 2020 and for each Fund that is a series of CEFT I and CETF II at the close of business on October 16, 2020 (previously defined as, the “Record Dates”). The number of votes to which each Fund or class is entitled is also presented for CETF I, CFST I and CFST II, each of whose By-Laws provide for dollar-based voting. See “Proxy Voting and Shareholder Meeting Information – Quorum and Methods of Tabulation” for additional information regarding the voting provisions applicable to each Trust.

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A-2