<SEC-DOCUMENT>0001104659-20-100179.txt : 20200828
<SEC-HEADER>0001104659-20-100179.hdr.sgml : 20200828
<ACCEPTANCE-DATETIME>20200828161145
ACCESSION NUMBER:		0001104659-20-100179
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200825
FILED AS OF DATE:		20200828
DATE AS OF CHANGE:		20200828

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			PATRICK GREGORY S
		CENTRAL INDEX KEY:			0001219844

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35518
		FILM NUMBER:		201147986

	MAIL ADDRESS:	
		STREET 1:		C/O SUPERNUS PHARMACEUTICALS, INC.
		STREET 2:		9715 KEY WEST AVENUE
		CITY:			ROCKVILLE
		STATE:			MD
		ZIP:			20850

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SUPERNUS PHARMACEUTICALS, INC.
		CENTRAL INDEX KEY:			0001356576
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		9715 KEY WEST AVENUE
		CITY:			ROCKVILLE
		STATE:			MD
		ZIP:			20850
		BUSINESS PHONE:		301-838-2500

	MAIL ADDRESS:	
		STREET 1:		9715 KEY WEST AVENUE
		CITY:			ROCKVILLE
		STATE:			MD
		ZIP:			20850

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SUPERNUS PHARMACEUTICALS INC
		DATE OF NAME CHANGE:	20060317
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>a4.xml
<DESCRIPTION>4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-08-25</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001356576</issuerCik>
        <issuerName>SUPERNUS PHARMACEUTICALS, INC.</issuerName>
        <issuerTradingSymbol>SUPN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001219844</rptOwnerCik>
            <rptOwnerName>PATRICK GREGORY S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O SUPERNUS PHARMACEUTICALS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>9715 KEY WEST AVENUE</rptOwnerStreet2>
            <rptOwnerCity>ROCKVILLE</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>20850</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Sr.VP, Chief Financial Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-08-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>45583</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-08-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1120</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>44463</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Includes an aggregate of 526 shares acquired by the Reporting Person through the Issuer's Employee Stock Purchase Plan subsequent to the date of the Reporting Person's most recent filing on Form 4.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Gregory S. Patrick</signatureName>
        <signatureDate>2020-08-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
