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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0000092122-03-000232.txt : 20031002
<SEC-HEADER>0000092122-03-000232.hdr.sgml : 20031002
<ACCEPTANCE-DATETIME>20031002123831
ACCESSION NUMBER:		0000092122-03-000232
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20031002
FILED AS OF DATE:		20031002

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			JAMES DONALD M
		CENTRAL INDEX KEY:			0001188417

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-03526
		FILM NUMBER:		03922984

	MAIL ADDRESS:	
		STREET 1:		C/O VULCAN MATERIALS COMPANY
		STREET 2:		1200 URBAN CENTER DRIVE
		CITY:			BIRMINGHAM
		STATE:			AL
		ZIP:			35242

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SOUTHERN CO
		CENTRAL INDEX KEY:			0000092122
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC SERVICES [4911]
		IRS NUMBER:				580690070
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		270 PEACHTREE ST
		CITY:			ATLANTA
		STATE:			GA
		ZIP:			30303
		BUSINESS PHONE:		4045065000

	MAIL ADDRESS:	
		STREET 1:		270 PEACHTREE STREET
		CITY:			ATLANTA
		STATE:			GA
		ZIP:			30303
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>

<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2003-10-02</periodOfReport>


    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000092122</issuerCik>
        <issuerName>SOUTHERN CO</issuerName>
        <issuerTradingSymbol>SO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001188417</rptOwnerCik>
            <rptOwnerName>JAMES DONALD M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>270 PEACHTREE STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ATLANTA</rptOwnerCity>
            <rptOwnerState>GA</rptOwnerState>
            <rptOwnerZipCode>30303</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>

        <derivativeTransaction>
            <securityTitle>
                <value>Deferred Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2003-10-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>196.26</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>29.3</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Southern Company Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>196.26</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>702.22</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>

    </derivativeTable>

    <footnotes>
        <footnote id="F1">Acquired pursuant to Southern's Deferred Compensation Pan payable in stock only upon termination.  There is no exercise or expiration date.</footnote>
    </footnotes>


    <ownerSignature>
        <signatureName>Patricia L. Roberts  Attorney in fact</signatureName>
        <signatureDate>2003-10-02</signatureDate>
    </ownerSignature>

</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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