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    PUBLIC DOCUMENT COUNT:		32
    FILED AS OF DATE:		20250605
    DATE AS OF CHANGE:		20250605

    SUBJECT COMPANY:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			FIRST INTERSTATE BANCSYSTEM INC
    		CENTRAL INDEX KEY:			0000860413
    		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
    		ORGANIZATION NAME:           	02 Finance
    		EIN:				810331430
    		STATE OF INCORPORATION:			DE
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		FWP
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	333-272215
    		FILM NUMBER:		251025107

    	BUSINESS ADDRESS:
    		STREET 1:		401 NO 31ST STREET
    		CITY:			BILLINGS
    		STATE:			MT
    		ZIP:			59101
    		BUSINESS PHONE:		4062555311

    	MAIL ADDRESS:
    		STREET 1:		401 NO 31ST STREET
    		CITY:			BILLINGS
    		STATE:			MT
    		ZIP:			59101

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	FIRST INTERSTATE BANCSYSTEM OF MONTANA INC
    		DATE OF NAME CHANGE:	19930615

    FILED BY:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			FIRST INTERSTATE BANCSYSTEM INC
    		CENTRAL INDEX KEY:			0000860413
    		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
    		ORGANIZATION NAME:           	02 Finance
    		EIN:				810331430
    		STATE OF INCORPORATION:			DE
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		FWP

    	BUSINESS ADDRESS:
    		STREET 1:		401 NO 31ST STREET
    		CITY:			BILLINGS
    		STATE:			MT
    		ZIP:			59101
    		BUSINESS PHONE:		4062555311

    	MAIL ADDRESS:
    		STREET 1:		401 NO 31ST STREET
    		CITY:			BILLINGS
    		STATE:			MT
    		ZIP:			59101

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	FIRST INTERSTATE BANCSYSTEM OF MONTANA INC
    		DATE OF NAME CHANGE:	19930615
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