<SEC-DOCUMENT>0001193125-18-172974-index.html : 20180524
<SEC-HEADER>0001193125-18-172974.hdr.sgml : 20180524
<ACCEPTANCE-DATETIME>20180524100157
ACCESSION NUMBER:		0001193125-18-172974
CONFORMED SUBMISSION TYPE:	497
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20180524
DATE AS OF CHANGE:		20180524
EFFECTIVENESS DATE:		20180524

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:		18856882

	BUSINESS ADDRESS:	
		STREET 1:		227 W MONROE STE 3000
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606
		BUSINESS PHONE:		3126349200

	MAIL ADDRESS:	
		STREET 1:		227 W MONROE STE 3000
		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
<SERIES-AND-CLASSES-CONTRACTS-DATA>
<EXISTING-SERIES-AND-CLASSES-CONTRACTS>
<SERIES>
<OWNER-CIK>0000002110
<SERIES-ID>S000009189
<SERIES-NAME>Columbia Thermostat Fund
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000024974
<CLASS-CONTRACT-NAME>Columbia Thermostat Fund Class A
<CLASS-CONTRACT-TICKER-SYMBOL>CTFAX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000024976
<CLASS-CONTRACT-NAME>Columbia Thermostat Fund Class C
<CLASS-CONTRACT-TICKER-SYMBOL>CTFDX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000024977
<CLASS-CONTRACT-NAME>Columbia Thermostat Fund Institutional Class
<CLASS-CONTRACT-TICKER-SYMBOL>COTZX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000122749
<CLASS-CONTRACT-NAME>Columbia Thermostat Fund Advisor Class
<CLASS-CONTRACT-TICKER-SYMBOL>CTORX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000122750
<CLASS-CONTRACT-NAME>Columbia Thermostat Fund Institutional 2 Class
<CLASS-CONTRACT-TICKER-SYMBOL>CQTRX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000122751
<CLASS-CONTRACT-NAME>Columbia Thermostat Fund Institutional 3 Class
<CLASS-CONTRACT-TICKER-SYMBOL>CYYYX
</CLASS-CONTRACT>
</SERIES>
</EXISTING-SERIES-AND-CLASSES-CONTRACTS>
</SERIES-AND-CLASSES-CONTRACTS-DATA>
</SEC-HEADER>
<DOCUMENT>
<TYPE>497
<SEQUENCE>1
<FILENAME>d593401d497.htm
<DESCRIPTION>COLUMBIA ACORN TRUST
<TEXT>
Document 1 - file: d593401d497.htm

</DOCUMENT>
</SEC-DOCUMENT>