-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 DS6hFcRL+Dg/DLvU9ul9w8OOte3+RVHblXqUtUdRti2yLNrE5w5MDq7olCleFnYP
 h1kYZfbo9yHsJy/VK0TfSA==

<SEC-DOCUMENT>0001209191-08-026894.txt : 20080501
<SEC-HEADER>0001209191-08-026894.hdr.sgml : 20080501
<ACCEPTANCE-DATETIME>20080501171608
ACCESSION NUMBER:		0001209191-08-026894
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080501
FILED AS OF DATE:		20080501
DATE AS OF CHANGE:		20080501

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LoopNet, Inc.
		CENTRAL INDEX KEY:			0001353209
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE AGENTS & MANAGERS (FOR OTHERS) [6531]
		IRS NUMBER:				770463987
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		185 BERRY STREET
		STREET 2:		SUITE 4000
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94107
		BUSINESS PHONE:		(415) 243-4200

	MAIL ADDRESS:	
		STREET 1:		185 BERRY STREET
		STREET 2:		SUITE 4000
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94107

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Warthen Wayne B
		CENTRAL INDEX KEY:			0001360348

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-52026
		FILM NUMBER:		08795650

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		626-803-5000

	MAIL ADDRESS:	
		STREET 1:		C/O LOOPNET, INC.
		STREET 2:		181 W. HUNTINGTON DRIVE, SUITE 208
		CITY:			MONROVIA
		STATE:			CA
		ZIP:			91016
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-05-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001353209</issuerCik>
        <issuerName>LoopNet, Inc.</issuerName>
        <issuerTradingSymbol>LOOP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001360348</rptOwnerCik>
            <rptOwnerName>Warthen Wayne B</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O LOOPNET, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>181 W. HUNTINGTON DRIVE, SUITE 208</rptOwnerStreet2>
            <rptOwnerCity>MONROVIA</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>91016</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Technology Officer &amp; SVP</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-05-01</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>12.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>244862</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Wayne B. Warthen and Monica L. Warthen Trust</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>169062</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person when not in possession of material non-public information.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Maria Valles as Attorney-in-Fact</signatureName>
        <signatureDate>2008-05-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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