<SEC-DOCUMENT>0000899243-18-004885.txt : 20180221
<SEC-HEADER>0000899243-18-004885.hdr.sgml : 20180221
<ACCEPTANCE-DATETIME>20180221180550
ACCESSION NUMBER:		0000899243-18-004885
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180217
FILED AS OF DATE:		20180221
DATE AS OF CHANGE:		20180221

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Lane Andrew R
		CENTRAL INDEX KEY:			0001297853

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35479
		FILM NUMBER:		18629870

	MAIL ADDRESS:	
		STREET 1:		MRC GLOBAL INC.
		STREET 2:		2 HOUSTON CENTER, 909 FANNIN, SUITE 3100
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77010

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MRC GLOBAL INC.
		CENTRAL INDEX KEY:			0001439095
		STANDARD INDUSTRIAL CLASSIFICATION:	WHOLESALE-INDUSTRIAL MACHINERY & EQUIPMENT [5084]
		IRS NUMBER:				205956993
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		FULBRIGHT TOWER
		STREET 2:		1301 MCKINNEY STREET, SUITE 2300
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77010
		BUSINESS PHONE:		877.294.7574

	MAIL ADDRESS:	
		STREET 1:		FULBRIGHT TOWER
		STREET 2:		1301 MCKINNEY STREET, SUITE 2300
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77010

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MCJUNKIN RED MAN HOLDING CORP
		DATE OF NAME CHANGE:	20080702
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-02-17</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001439095</issuerCik>
        <issuerName>MRC GLOBAL INC.</issuerName>
        <issuerTradingSymbol>MRC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001297853</rptOwnerCik>
            <rptOwnerName>Lane Andrew R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>FULBRIGHT TOWER</rptOwnerStreet1>
            <rptOwnerStreet2>1301 MCKINNEY ST., SUITE 2300</rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77010</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President &amp; CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-02-17</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>8327</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>16.73</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>847086</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Through a Limited Partnership</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-02-18</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>69402</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>16.73</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>777684</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Through a Limited Partnership</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The reporting person surrendered these shares to satisfy tax withholding obligations resulting from the vesting of certain shares of the issuer's Common Stock and certain Restricted Stock Units of the issuer.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Ann D. Garnett, by power of attorney</signatureName>
        <signatureDate>2018-02-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
