Columbia Acorn Trust
290 Congress Street
Boston, MA 02210

May 1, 2025

VIA EDGAR

Mr. Mark Cowan

U.S. Securities and Exchange Commission
Division of Investment Management, Disclosure Review Office
100 F Street, N.E.
Washington, D.C. 20549

RE:

Columbia Acorn Trust (the Registrant)
Columbia Acorn European Fund
Columbia Acorn Fund
Columbia Acorn International
Columbia International Select
Columbia Thermostat Fund

 

Post-Effective Amendment No. 119
File No. 002-34223 /811-01829

Dear Mr. Cowan:

Pursuant to Rule 497(j) under the Securities Act of 1933, as amended, please accept this letter as certification that the prospectuses and Statement of Additional Information for the above-referenced funds do not differ from that contained in Registrant’s Post-Effective Amendment No. 119 (Amendment). This Amendment was filed electronically on April 25, 2025.

If you have any questions, please contact either me at (212) 850-1703 or Andrew Kirn at (612) 678-9052.

Sincerely, 

Joseph D'Alessandro

Assistant Secretary

Columbia Acorn Trust