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<ACCEPTANCE-DATETIME>20200818132402
ACCESSION NUMBER:		0001193125-20-223321
CONFORMED SUBMISSION TYPE:	497
PUBLIC DOCUMENT COUNT:		16
FILED AS OF DATE:		20200818
DATE AS OF CHANGE:		20200818
EFFECTIVENESS DATE:		20200818

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			COLUMBIA ACORN TRUST
		CENTRAL INDEX KEY:			0000002110
		IRS NUMBER:				362692100
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		497
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	002-34223
		FILM NUMBER:		201112850

	BUSINESS ADDRESS:	
		STREET 1:		71 S. WACKER DRIVE, SUITE 2500
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606
		BUSINESS PHONE:		3126349200

	MAIL ADDRESS:	
		STREET 1:		71 S. WACKER DRIVE, SUITE 2500
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	LIBERTY ACORN TRUST
		DATE OF NAME CHANGE:	20010424

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ACORN INVESTMENT TRUST
		DATE OF NAME CHANGE:	19940204

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ACORN FUND INC
		DATE OF NAME CHANGE:	19920703
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<OWNER-CIK>0000002110
<SERIES-ID>S000009188
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<CLASS-CONTRACT-NAME>Columbia Acorn International Select Class A
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<CLASS-CONTRACT-ID>C000024973
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<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000122746
<CLASS-CONTRACT-NAME>Columbia Acorn International Select Institutional 2 Class
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<CLASS-CONTRACT-ID>C000122747
<CLASS-CONTRACT-NAME>Columbia Acorn International Select Institutional 3 Class
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<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000122748
<CLASS-CONTRACT-NAME>Columbia Acorn International Select Advisor Class
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</CLASS-CONTRACT>
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<DOCUMENT>
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<FILENAME>d33205d497.htm
<DESCRIPTION>COLUMBIA ACORN TRUST
<TEXT>
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Document 12 - file: Financial_Report.xlsx

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