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

    <schemaVersion>X0407</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2023-07-11</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000727273</issuerCik>
        <issuerName>CADIZ INC</issuerName>
        <issuerTradingSymbol>CDZI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001751484</rptOwnerCik>
            <rptOwnerName>Dreyfus Maria S.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CADIZ INC.</rptOwnerStreet1>
            <rptOwnerStreet2>550 SOUTH HOPE STREET, SUITE 2850</rptOwnerStreet2>
            <rptOwnerCity>LOS ANGELES</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90071</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2023-07-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4699</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.99</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6115</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2023-07-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4676</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>4.01</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10791</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Shares allocated to the Reporting Person under the 2019 Equity Incentive Plan in lieu of cash compensation for services rendered by the Reporting Person as a director of the Issuer during the 3-month period beginning April 1, 2023.</footnote>
        <footnote id="F2">Shares allocated to the Reporting Person under the 2019 Equity Incentive Plan in lieu of cash compensation for services rendered by the Reporting Person as a director of the Issuer for the 3-month period beginning July 1, 2023.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Maria Jelescu Dreyfus</signatureName>
        <signatureDate>2023-07-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
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X0407
4
2023-07-11
0
0000727273
CADIZ INC
CDZI
0001751484
Dreyfus Maria S.
C/O CADIZ INC.
550 SOUTH HOPE STREET, SUITE 2850
LOS ANGELES
CA
90071
1
0
0
0
0
Common Stock
2023-07-11
4
A
0
4699
3.99
A
6115
D
Common Stock
2023-07-11
4
A
0
4676
4.01
A
10791
D
Shares allocated to the Reporting Person under the 2019 Equity Incentive Plan in lieu of cash compensation for services rendered by the Reporting Person as a director of the Issuer during the 3-month period beginning April 1, 2023.
Shares allocated to the Reporting Person under the 2019 Equity Incentive Plan in lieu of cash compensation for services rendered by the Reporting Person as a director of the Issuer for the 3-month period beginning July 1, 2023.
Maria Jelescu Dreyfus
2023-07-13