<SEC-DOCUMENT>0001127602-21-009705.txt : 20210308
<SEC-HEADER>0001127602-21-009705.hdr.sgml : 20210308
<ACCEPTANCE-DATETIME>20210308165223
ACCESSION NUMBER:		0001127602-21-009705
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210304
FILED AS OF DATE:		20210308
DATE AS OF CHANGE:		20210308

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Click Christopher A
		CENTRAL INDEX KEY:			0001831593

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35914
		FILM NUMBER:		21722634

	MAIL ADDRESS:	
		STREET 1:		200 PEACH ST
		CITY:			EL DORADO
		STATE:			AR
		ZIP:			71731

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Murphy USA Inc.
		CENTRAL INDEX KEY:			0001573516
		STANDARD INDUSTRIAL CLASSIFICATION:	RETAIL-AUTO DEALERS & GASOLINE STATIONS [5500]
		IRS NUMBER:				462279221
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		200 PEACH STREET
		CITY:			EL DORADO
		STATE:			AR
		ZIP:			71730-5836
		BUSINESS PHONE:		(870) 875-7600

	MAIL ADDRESS:	
		STREET 1:		200 PEACH STREET
		CITY:			EL DORADO
		STATE:			AR
		ZIP:			71730-5836
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-03-04</periodOfReport>

    <issuer>
        <issuerCik>0001573516</issuerCik>
        <issuerName>Murphy USA Inc.</issuerName>
        <issuerTradingSymbol>MUSA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001831593</rptOwnerCik>
            <rptOwnerName>Click Christopher A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>200 E. PEACH ST</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>EL DORADO</rptOwnerCity>
            <rptOwnerState>AR</rptOwnerState>
            <rptOwnerZipCode>71730</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>SVP, Strategy &amp; Development</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Dividend Equivalent Units</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2021-03-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1.693</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1.693</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1.693</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Reflects dividend equivalent units accrued on RSUs granted to the Reporting Person under the Plan. Each dividend equivalent unit reflects the right to receive common stock, subject to the terms and conditions (including vesting and settlement terms) applicable to the corresponding RSUs.</footnote>
        <footnote id="F2">Reflects the accrual of dividend equivalent units on RSUs granted to the Reporting Person on February 7, 2021.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Gregory L. Smith, attorney-in-fact</signatureName>
        <signatureDate>2021-03-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
