<SEC-DOCUMENT>0001140361-19-006948-index.html : 20190412
<SEC-HEADER>0001140361-19-006948.hdr.sgml : 20190412
<ACCEPTANCE-DATETIME>20190411173919
ACCESSION NUMBER:		0001140361-19-006948
CONFORMED SUBMISSION TYPE:	DEFA14A
PUBLIC DOCUMENT COUNT:		5
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:		DEFA14A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-20288
		FILM NUMBER:		19744573

	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
</SEC-HEADER>
<DOCUMENT>
<TYPE>DEFA14A
<SEQUENCE>1
<FILENAME>nc10000953x1_defa14a.htm
<DESCRIPTION>DEFA14A
<TEXT>
Document 1 - file: nc10000953x1_defa14a.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>2
<FILENAME>nc10000953x1_pc01.jpg
<TEXT>
Document 2 - file: nc10000953x1_pc01.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>3
<FILENAME>nc10000953x1_pc02.jpg
<TEXT>
Document 3 - file: nc10000953x1_pc02.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>4
<FILENAME>nc10000953x1_pc03.jpg
<TEXT>
Document 4 - file: nc10000953x1_pc03.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>5
<FILENAME>nc10000953x1_pc04.jpg
<TEXT>
Document 5 - file: nc10000953x1_pc04.jpg

</DOCUMENT>
</SEC-DOCUMENT>