<SEC-DOCUMENT>0001140361-19-006947-index.html : 20190412
<SEC-HEADER>0001140361-19-006947.hdr.sgml : 20190412
<ACCEPTANCE-DATETIME>20190411173812
ACCESSION NUMBER:		0001140361-19-006947
CONFORMED SUBMISSION TYPE:	DEF 14A
PUBLIC DOCUMENT COUNT:		18
CONFORMED PERIOD OF REPORT:	20190522
FILED AS OF DATE:		20190412
DATE AS OF CHANGE:		20190411
EFFECTIVENESS DATE:		20190412

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:		19744570

	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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