<SEC-DOCUMENT>0001140361-18-018485-index.html : 20180413
<SEC-HEADER>0001140361-18-018485.hdr.sgml : 20180413
<ACCEPTANCE-DATETIME>20180413131056
ACCESSION NUMBER:		0001140361-18-018485
CONFORMED SUBMISSION TYPE:	DEF 14A
PUBLIC DOCUMENT COUNT:		26
CONFORMED PERIOD OF REPORT:	20180523
FILED AS OF DATE:		20180413
DATE AS OF CHANGE:		20180413
EFFECTIVENESS DATE:		20180413

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			COLUMBIA BANKING SYSTEM INC
		CENTRAL INDEX KEY:			0000887343
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				911422237
		STATE OF INCORPORATION:			WA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		DEF 14A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-20288
		FILM NUMBER:		18753809

	BUSINESS ADDRESS:	
		STREET 1:		1301 A STREET
		CITY:			TACOMA
		STATE:			WA
		ZIP:			98402
		BUSINESS PHONE:		2533051900

	MAIL ADDRESS:	
		STREET 1:		1301 A STREET
		CITY:			TACOMA
		STATE:			WA
		ZIP:			98402
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