<SEC-DOCUMENT>0001127602-13-011752.txt : 20130321
<SEC-HEADER>0001127602-13-011752.hdr.sgml : 20130321
<ACCEPTANCE-DATETIME>20130321201957
ACCESSION NUMBER:		0001127602-13-011752
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20130319
FILED AS OF DATE:		20130321
DATE AS OF CHANGE:		20130321

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Hoerner John E.
		CENTRAL INDEX KEY:			0001529248

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34474
		FILM NUMBER:		13708941

	MAIL ADDRESS:	
		STREET 1:		2511 GARDEN ROAD
		STREET 2:		BUILDING A, SUITE 200
		CITY:			MONTEREY
		STATE:			CA
		ZIP:			93940

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CENTURY ALUMINUM CO
		CENTRAL INDEX KEY:			0000949157
		STANDARD INDUSTRIAL CLASSIFICATION:	PRIMARY PRODUCTION OF ALUMINUM [3334]
		IRS NUMBER:				133070826
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2511 GARDEN ROAD
		STREET 2:		BUILDING A SUITE 200
		CITY:			MONTEREY
		STATE:			CA
		ZIP:			93940
		BUSINESS PHONE:		3042736000

	MAIL ADDRESS:	
		STREET 1:		2511 GARDEN ROAD
		STREET 2:		BUILDING A SUITE 200
		CITY:			MONTEREY
		STATE:			CA
		ZIP:			93940
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2013-03-19</periodOfReport>

    <issuer>
        <issuerCik>0000949157</issuerCik>
        <issuerName>CENTURY ALUMINUM CO</issuerName>
        <issuerTradingSymbol>CENX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001529248</rptOwnerCik>
            <rptOwnerName>Hoerner John E.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>CENTURY ALUMINUM COMPANY</rptOwnerStreet1>
            <rptOwnerStreet2>2511 GARDEN ROAD, BUILDING A, SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>MONTEREY</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>93940</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>VP of N. American Operations</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2013-03-19</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>9112</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>32146</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2013-03-19</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>11222</value>
                    <footnoteId id="F3"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>43368</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares of common stock acquired by the Reporting Person upon the vesting of performance share units granted pursuant to the Issuer's 2012-2014 Performance Share Program (&quot;2012-2014 Plan Period &quot;) under a Rule 16b-3(d) plan, all of which will vest in the ordinary course on the last day of the 2012-2014 Plan Period, December 31, 2014.</footnote>
        <footnote id="F2">Includes the remaining 10,000 unvested performance share units granted to the Reporting Person upon becoming the Issuer's Vice President of North American Operations which will vest on February 28, 2014, and unvested performance share units granted to the Reporting Person pursuant to the Issuer's 2012-2014 Performance Share Program, all under a Rule 16b-3(d) plan.</footnote>
        <footnote id="F3">Represents shares of common stock acquired by the Reporting Person upon the vesting of performance share units granted pursuant to the Issuer's 2013-2015 Performance Share Program (&quot;Plan Period &quot;) under a Rule 16b-3(d) plan, all of which will vest in the ordinary course on the last day of the Plan Period, December 31, 2015.</footnote>
        <footnote id="F4">Includes the remaining 10,000 unvested performance share units granted to the Reporting Person upon becoming the Issuer's Vice President of North American Operations which will vest on February 28, 2014, and unvested performance share units granted to the Reporting Person pursuant to the Issuer's 2012-2014 and 2013-2015 Performance Share Programs, all under a Rule 16b-3(d) plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Michael A. Serafini, Attorney-in-Fact for John E. Hoerner</signatureName>
        <signatureDate>2013-03-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
