<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-08-16</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000750199</issuerCik>
        <issuerName>ENERGY PARTNERS LTD</issuerName>
        <issuerTradingSymbol>EPL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001044292</rptOwnerCik>
            <rptOwnerName>BACHMANN RICHARD A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ENERGY PARTNERS, LTD.</rptOwnerStreet1>
            <rptOwnerStreet2>201 ST. CHARLES AVENUE, SUITE 3400</rptOwnerStreet2>
            <rptOwnerCity>NEW ORLEANS</rptOwnerCity>
            <rptOwnerState>LA</rptOwnerState>
            <rptOwnerZipCode>70170</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman and CEO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Forward Purchase Agreement</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2006-08-16</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2006-08-16</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2009-08-17</value>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>39400</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">This Form 4 is being filed in connection with the sale by the Reporting Person of 39,400 shares of common stock of Energy Partners, Ltd. to an unaffiliated counterparty pursuant to a forward purchase agreement.  On August 17, 2009, the date specified in the sale confirmation pursuant to the agreement (or earlier if the agreement is terminated early), the Reporting Person is obligated to deliver the following number of shares of common stock (or, at his election, the cash equivalent of such shares): (a) if the closing price of the Company common stock on the maturity date (the &quot;PDP&quot;)  is less than $18.0248 per share (the &quot;DPP&quot;),  39,400 shares, (b) if the PDP is equal to or greater than the DPP, but less than $21.6290 per share (the &quot;CUP&quot;),  39,400 times a fraction equal to the DPP divided by the PDP and (c) if the PDP is equal to or greater than the CUP,  39,400  times a fraction equal to 1 minus [the CUP minus the DPP] divided by the PDP.</footnote>
        <footnote id="F2">(footnote one continued)  The share numbers and price amounts are subject to anti-dilution adjustments.  To secure each party?s obligations under the agreement, the Reporting Person has pledged 39,400 shares to the counterparty, and the counterparty has pledged $710,303  in cash to the Reporting Person.  The Reporting Person is entitled to vote the shares during the term of the agreement.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ John H. Peper (Attorney-In-Fact for Richard A. Bachmann)</signatureName>
        <signatureDate>2006-08-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
