<SUBMISSION>
<ACCESSION-NUMBER>0001163739-08-000065
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20080930
<FILING-DATE>20081001
<DATE-OF-FILING-DATE-CHANGE>20081001
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>PETRELLO ANTHONY G
<CIK>0001195669
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>001-32657
<FILM-NUMBER>081098973
</FILING-VALUES>
<MAIL-ADDRESS>
<STREET1>NABORS CORP SERVICES
<STREET2>515 W GREENS RD SUITE 1200`
<CITY>HOUSTON
<STATE>TX
<ZIP>77067
</MAIL-ADDRESS>
</REPORTING-OWNER>
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>NABORS INDUSTRIES LTD
<CIK>0001163739
<ASSIGNED-SIC>1381
<IRS-NUMBER>980363970
<STATE-OF-INCORPORATION>D0
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>MINTFLOWER PLACE
<STREET2>8 PAR-LA-VILLE ROAD
<CITY>HAMILTON, HM08
<STATE>D0
<ZIP>0000
<PHONE>2464219471
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>P O BOX HM3349
<CITY>HAMILTON, HMPX
<STATE>D0
<ZIP>0000
</MAIL-ADDRESS>
</ISSUER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-09-30</periodOfReport>

    <issuer>
        <issuerCik>0001163739</issuerCik>
        <issuerName>NABORS INDUSTRIES LTD</issuerName>
        <issuerTradingSymbol>NBR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001195669</rptOwnerCik>
            <rptOwnerName>PETRELLO ANTHONY G</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NABORS CORPORATE SERVICES</rptOwnerStreet1>
            <rptOwnerStreet2>515 WEST GREENS ROAD</rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77067</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>PRESIDENT AND COO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-09-30</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2008-09-30</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>11868</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>23.26</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3447258</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Owned directly or indirectly by revocable trust of which the Reporting Person is a trustee and as to which the Reporting Person has voting and dispositive power.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Lisa Wysocki by Power of Attorney for AnthonyG. Petrello</signatureName>
        <signatureDate>2008-10-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
