<SEC-DOCUMENT>0000866273-22-000081.txt : 20220901
<SEC-HEADER>0000866273-22-000081.hdr.sgml : 20220901
<ACCEPTANCE-DATETIME>20220901151601
ACCESSION NUMBER:		0000866273-22-000081
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20220830
FILED AS OF DATE:		20220901
DATE AS OF CHANGE:		20220901

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			RODGERS GLYN A
		CENTRAL INDEX KEY:			0001786694

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15461
		FILM NUMBER:		221220750

	MAIL ADDRESS:	
		STREET 1:		5100 EAST SKELLY DRIVE
		STREET 2:		SUITE 100
		CITY:			TULSA
		STATE:			OK
		ZIP:			74135

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MATRIX SERVICE CO
		CENTRAL INDEX KEY:			0000866273
		STANDARD INDUSTRIAL CLASSIFICATION:	CONSTRUCTION SPECIAL TRADE CONTRACTORS [1700]
		IRS NUMBER:				731352174
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		5100 EAST SKELLY DRIVE
		STREET 2:		SUITE 500
		CITY:			TULSA
		STATE:			OK
		ZIP:			74135
		BUSINESS PHONE:		9188388822

	MAIL ADDRESS:	
		STREET 1:		5100 EAST SKELLY DRIVE
		STREET 2:		SUITE 500
		CITY:			TULSA
		STATE:			OK
		ZIP:			74135
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_166205973699260.xml
<DESCRIPTION>FORM 4
<TEXT>
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        <issuerName>MATRIX SERVICE CO</issuerName>
        <issuerTradingSymbol>MTRX</issuerTradingSymbol>
    </issuer>

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            <rptOwnerName>RODGERS GLYN A</rptOwnerName>
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            <rptOwnerStreet1>5100 EAST SKELLY DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 100</rptOwnerStreet2>
            <rptOwnerCity>TULSA</rptOwnerCity>
            <rptOwnerState>OK</rptOwnerState>
            <rptOwnerZipCode>74135</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President, Matrix PDM Eng</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
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            <transactionCoding>
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                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
                    <value>742</value>
                    <footnoteId id="F3"/>
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                <transactionAcquiredDisposedCode>
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                <sharesOwnedFollowingTransaction>
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                </sharesOwnedFollowingTransaction>
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                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>COMMON STOCK</value>
                <footnoteId id="F1"/>
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                <value>2022-08-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>10307</value>
                    <footnoteId id="F4"/>
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                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F5"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
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            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>32914</value>
                    <footnoteId id="F6"/>
                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>RESTRICTED STOCK UNITS</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2022-08-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
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            <transactionAmounts>
                <transactionShares>
                    <value>2163</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2022-08-30</value>
                <footnoteId id="F7"/>
            </exerciseDate>
            <expirationDate>
                <value>2025-08-30</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>COMMON STOCK</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2163.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6486</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
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            <securityTitle>
                <value>RESTRICTED STOCK UNITS</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
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            <transactionDate>
                <value>2022-08-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10307</value>
                    <footnoteId id="F8"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F5"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2023-08-30</value>
            </exerciseDate>
            <expirationDate>
                <value>2026-08-30</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>COMMON STOCK</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>10307.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10307</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">MATRIX SERVICE COMPANY COMMON STOCK.</footnote>
        <footnote id="F2">EACH RESTRICTED STOCK UNIT IS THE ECONOMIC EQUIVALENT OF ONE SHARE OF MATRIX SERVICE COMPANY COMMON STOCK. ALL RESTRICTED STOCK UNITS ARE SETTLED SOLELY IN CASH WHEN VESTED.</footnote>
        <footnote id="F3">RESTRICTED STOCK UNIT AWARD - SHARES DISPOSED TO SATISFY TAX OBLIGATION DUE ON VEST DATE FOR SERVICE-BASED GRANT.</footnote>
        <footnote id="F4">RESTRICTED STOCK UNIT - EACH UNIT WILL ENTITLE THE REPORTING PERSON TO ONE SHARE OF MATRIX SERVICE COMPANY COMMON STOCK IF AND WHEN THE CONDITIONS OF THE RESTRICTION HAVE BEEN SATISFIED.  FOR THIS GRANT, 25% WILL VEST EACH YEAR FOR THE NEXT FOUR YEARS ON THE ANNIVERSARY DATES.</footnote>
        <footnote id="F5">NOT APPLICABLE.</footnote>
        <footnote id="F6">INCLUDES 10,448 SHARES OF MATRIX SERVICE COMPANY COMMON STOCK OWNED OUTRIGHT.</footnote>
        <footnote id="F7">FOR THIS SERVICE-BASED AWARD OF CASH-SETTLED RESTRICTED STOCK UNITS, 25% WILL VEST EACH YEAR FROM AUGUST 30, 2022 TO AUGUST 30, 2025.</footnote>
        <footnote id="F8">EACH UNIT WILL ENTITLE THE REPORTING PERSON TO THE CASH EQUIVALENT OF ONE SHARE OF MATRIX SERVICE COMPANY COMMON STOCK IF AND WHEN THE CONDITIONS OF THE RESTRICTION HAVE BEEN SATISFIED. FOR THIS GRANT, 25% WILL VEST EACH YEAR FOR THE NEXT FOUR YEARS ON THE ANNIVERSARY DATES.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Glyn A. Rodgers</signatureName>
        <signatureDate>2022-09-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
