<SEC-DOCUMENT>0001209191-20-057023.txt : 20201104
<SEC-HEADER>0001209191-20-057023.hdr.sgml : 20201104
<ACCEPTANCE-DATETIME>20201104194124
ACCESSION NUMBER:		0001209191-20-057023
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20201102
FILED AS OF DATE:		20201104
DATE AS OF CHANGE:		20201104

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ROBERTSON ANGUS JAMES BRUCE
		CENTRAL INDEX KEY:			0001775887

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-26041
		FILM NUMBER:		201288194

	MAIL ADDRESS:	
		STREET 1:		C/O F5 NETWORKS, INC.
		STREET 2:		401 ELLIOTT AVE. WEST
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98119

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			F5 NETWORKS, INC.
		CENTRAL INDEX KEY:			0001048695
		STANDARD INDUSTRIAL CLASSIFICATION:	COMPUTER COMMUNICATIONS EQUIPMENT [3576]
		IRS NUMBER:				911714307
		STATE OF INCORPORATION:			WA
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		401 ELLIOTT AVENUE WEST
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98119
		BUSINESS PHONE:		2062725555

	MAIL ADDRESS:	
		STREET 1:		401 ELLIOTT AVENUE WEST
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98119

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	F5 NETWORKS INC
		DATE OF NAME CHANGE:	19990308

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	F5 LABS INC
		DATE OF NAME CHANGE:	19990305
</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>2020-11-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001048695</issuerCik>
        <issuerName>F5 NETWORKS, INC.</issuerName>
        <issuerTradingSymbol>FFIV</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001775887</rptOwnerCik>
            <rptOwnerName>ROBERTSON ANGUS JAMES BRUCE</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O F5 NETWORKS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>801 5TH AVENUE</rptOwnerStreet2>
            <rptOwnerCity>SEATTLE</rptOwnerCity>
            <rptOwnerState>WA</rptOwnerState>
            <rptOwnerZipCode>98104</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>SVP &amp; GM, Nginx</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Unit</value>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.00</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2020-11-02</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>9526</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>9526</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9526</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each Restricted Stock Unit represents a contingent right to receive one share of F5 Networks, Inc. Common Stock on the vest date.</footnote>
        <footnote id="F2">Concurrent with the award of 9,526 service-based Restricted Stock Units, the Company granted the reporting person additional Restricted
Stock Units that vest based on performance targets (&quot;Performance RSUs&quot;). If the performance targets are achieved at 100%, the reporting person will receive 9,526 Performance RSUs over the vesting period; the actual number of Performance RSUs received may be more or less depending on whether and to the extent that performance is greater than or less than targets. The Performance RSUs vests over a three-year period in three equal annual installments. Performance RSUs are not reported in Table II; the underlying shares of Performance RSUs will be reported in Table I if and when the Compensation Committee of the Board of Directors determines that the performance targets have been achieved.</footnote>
        <footnote id="F3">This November 2, 2020 award of service-based Restricted Stock Units vests in twelve equal quarterly increments beginning February 1, 2021.</footnote>
        <footnote id="F4">If the reporting person continues to provide services to the Company through the vest date, the corresponding number of shares of Common Stock of F5 Networks, Inc. will be issued to the reporting person on the vest date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Scot F. Rogers by Power of Attorney</signatureName>
        <signatureDate>2020-11-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
