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    <ACCEPTANCE-DATETIME>20231219070019
    ACCESSION NUMBER:		0000949157-23-000074
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		17
    CONFORMED PERIOD OF REPORT:	20231219
    ITEM INFORMATION:		Regulation FD Disclosure
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20231219
    DATE AS OF CHANGE:		20231219

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			CENTURY ALUMINUM CO
    		CENTRAL INDEX KEY:			0000949157
    		STANDARD INDUSTRIAL CLASSIFICATION:	PRIMARY PRODUCTION OF ALUMINUM [3334]
    		ORGANIZATION NAME:           	04 Manufacturing
    		IRS NUMBER:				133070826
    		STATE OF INCORPORATION:			DE
    		FISCAL YEAR END:			1231

    	FILING VALUES:
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    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-34474
    		FILM NUMBER:		231495599

    	BUSINESS ADDRESS:
    		STREET 1:		1 SOUTH WACKER DRIVE
    		STREET 2:		SUITE 1000
    		CITY:			CHICAGO
    		STATE:			IL
    		ZIP:			60606
    		BUSINESS PHONE:		3126963101

    	MAIL ADDRESS:
    		STREET 1:		1 SOUTH WACKER DRIVE
    		STREET 2:		SUITE 1000
    		CITY:			CHICAGO
    		STATE:			IL
    		ZIP:			60606
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    <FILENAME>cenx-20231219.htm
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    Document 1 - file: cenx-20231219.htm

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    <FILENAME>inflationreductionact45x.htm
    <DESCRIPTION>EX-99.1
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    Document 2 - file: inflationreductionact45x.htm

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    <FILENAME>cenx-20231219.xsd
    <DESCRIPTION>XBRL TAXONOMY EXTENSION SCHEMA DOCUMENT
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    <FILENAME>inflationreductionact45x001.jpg
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