<SEC-DOCUMENT>0001179110-18-007121.txt : 20180518
<SEC-HEADER>0001179110-18-007121.hdr.sgml : 20180518
<ACCEPTANCE-DATETIME>20180518162515
ACCESSION NUMBER:		0001179110-18-007121
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180517
FILED AS OF DATE:		20180518
DATE AS OF CHANGE:		20180518

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Perisich John M.
		CENTRAL INDEX KEY:			0001441444

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34145
		FILM NUMBER:		18846963

	MAIL ADDRESS:	
		STREET 1:		26000 COMMERCENTRE DR.
		CITY:			LAKE FOREST
		STATE:			CA
		ZIP:			92630

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Primoris Services Corp
		CENTRAL INDEX KEY:			0001361538
		STANDARD INDUSTRIAL CLASSIFICATION:	WATER, SEWER, PIPELINE, COMM AND POWER LINE CONSTRUCTION [1623]
		IRS NUMBER:				204743916
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2100 MCKINNEY AVENUE, SUITE 1500
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75201
		BUSINESS PHONE:		214-740-5600

	MAIL ADDRESS:	
		STREET 1:		2100 MCKINNEY AVENUE, SUITE 1500
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75201

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Primoris Services CORP
		DATE OF NAME CHANGE:	20080821

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Rhapsody Acquisition Corp.
		DATE OF NAME CHANGE:	20060503
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-05-17</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001361538</issuerCik>
        <issuerName>Primoris Services Corp</issuerName>
        <issuerTradingSymbol>PRIM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001441444</rptOwnerCik>
            <rptOwnerName>Perisich John M.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O PRIMORIS SERVICES CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>2100 MCKINNEY AVENUE, SUITE 1500</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Executive VP &amp; General Counsel</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-05-17</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>9055</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>25.14</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>136941</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Family Trust</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">These shares are owned directly by the Perisich Family Trust dated July 11, 2007 and indirectly by John M. Perisich, as trustee of the trust.  Mr. Perisich is Executive Vice President, General Counsel of Primoris.</footnote>
        <footnote id="F2">The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $25.04 to $25.21 per share, inclusive. The holder undertakes to provide to the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Peter J. Moerbeek, by power of attorney</signatureName>
        <signatureDate>2018-05-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
