<SEC-DOCUMENT>0000860413-18-000002-index.html : 20180123
<SEC-HEADER>0000860413-18-000002.hdr.sgml : 20180123
<ACCEPTANCE-DATETIME>20180123143343
ACCESSION NUMBER:		0000860413-18-000002
CONFORMED SUBMISSION TYPE:	8-K
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20180123
ITEM INFORMATION:		Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers
ITEM INFORMATION:		Financial Statements and Exhibits
FILED AS OF DATE:		20180123
DATE AS OF CHANGE:		20180123

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FIRST INTERSTATE BANCSYSTEM INC
		CENTRAL INDEX KEY:			0000860413
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				810331430
		STATE OF INCORPORATION:			MT
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		8-K
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34653
		FILM NUMBER:		18542043

	BUSINESS ADDRESS:	
		STREET 1:		P O BOX 30918
		STREET 2:		401 NO 31ST STREET
		CITY:			BILLINGS
		STATE:			MT
		ZIP:			59116-0918
		BUSINESS PHONE:		4062555300

	MAIL ADDRESS:	
		STREET 1:		P O BOX 30918
		STREET 2:		401 NO 31ST STREET
		CITY:			BILLINGS
		STATE:			MT
		ZIP:			59116-0918

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FIRST INTERSTATE BANCSYSTEM OF MONTANA INC
		DATE OF NAME CHANGE:	19930615
</SEC-HEADER>
<DOCUMENT>
<TYPE>8-K
<SEQUENCE>1
<FILENAME>a8-k20180123.htm
<DESCRIPTION>8-K
<TEXT>
Document 1 - file: a8-k20180123.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-99.1
<SEQUENCE>2
<FILENAME>ex991pressrelease20180123.htm
<DESCRIPTION>EXHIBIT 99.1
<TEXT>
Document 2 - file: ex991pressrelease20180123.htm

</DOCUMENT>
</SEC-DOCUMENT>