<SEC-DOCUMENT>0000860413-18-000075.txt : 20180509
<SEC-HEADER>0000860413-18-000075.hdr.sgml : 20180509
<ACCEPTANCE-DATETIME>20180509172523
ACCESSION NUMBER:		0000860413-18-000075
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180507
FILED AS OF DATE:		20180509
DATE AS OF CHANGE:		20180509

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Scott Jonathan R
		CENTRAL INDEX KEY:			0001361935

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34653
		FILM NUMBER:		18819549

	MAIL ADDRESS:	
		STREET 1:		P.O. BOX 30918
		CITY:			BILLINGS
		STATE:			MT
		ZIP:			59116

ISSUER:		

	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

	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>4
<SEQUENCE>1
<FILENAME>wf-form4_152590106825778.xml
<DESCRIPTION>FORM 4
<TEXT>
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        <issuerTradingSymbol>FIBK</issuerTradingSymbol>
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            <rptOwnerName>Scott Jonathan R</rptOwnerName>
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            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BILLINGS</rptOwnerCity>
            <rptOwnerState>MT</rptOwnerState>
            <rptOwnerZipCode>59116-0191</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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                <transactionFormType>4</transactionFormType>
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                <transactionShares>
                    <value>15244</value>
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                <transactionAcquiredDisposedCode>
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                <sharesOwnedFollowingTransaction>
                    <value>5054</value>
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                <directOrIndirectOwnership>
                    <value>D</value>
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        </nonDerivativeTransaction>
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            <securityTitle>
                <value>Class A Common Stock</value>
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                <sharesOwnedFollowingTransaction>
                    <value>4576</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
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                <natureOfOwnership>
                    <value>By Spouse</value>
                </natureOfOwnership>
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        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class A Common Stock</value>
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                <sharesOwnedFollowingTransaction>
                    <value>13188</value>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
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                <natureOfOwnership>
                    <value>By Trust</value>
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    <derivativeTable>
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            <securityTitle>
                <value>Stock Options (Right to Buy)</value>
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            <conversionOrExercisePrice>
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            <transactionDate>
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                <transactionFormType>4</transactionFormType>
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                <transactionShares>
                    <value>4000</value>
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            <securityTitle>
                <value>Stock Options (Right to Buy)</value>
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                <value>2020-02-15</value>
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                <underlyingSecurityTitle>
                    <value>Class A Common Stock</value>
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                    <value>0</value>
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            <securityTitle>
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                <underlyingSecurityTitle>
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                    <value>50000.0</value>
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                <sharesOwnedFollowingTransaction>
                    <value>50000</value>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
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            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.0</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>600322.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>600322</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust</value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $41.05 to $41.175, inclusive. The reporting person undertakes to provide to the company, any security holder of the company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above.</footnote>
        <footnote id="F2">The Class B Common Stock is convertible at any time into Class A Common Stock on a share for share basis at the discretion of the holder.  The conversion feature of the Class B Common Stock does not expire and the reporting person elected to convert the shares upon receipt.</footnote>
        <footnote id="F3">The Class B Common Stock is convertible at any time into Class A Common Stock on a share for share basis at the discretion of the holder.  The conversion feature of the Class B Common Stock does not expire.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/S/ Kirk D. Jensen, Attorney-in-Fact for Reporting Person</signatureName>
        <signatureDate>2018-05-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
