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            <filer>
                <filerCredentials>
                    <cik>0001341639</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



        </filerInfo>
    </headerData>
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        <issuerInfo>
            <issuerCik>0000015615</issuerCik>
            <issuerName>MASTEC INC.</issuerName>
            <secFileNumber>001-08106</secFileNumber>
            <issuerAddress>
                <ns2:street1>800 S. Douglas Road, 12th Floor</ns2:street1>
                <ns2:city>Coral Gables</ns2:city>
                <ns2:stateOrCountry>FL</ns2:stateOrCountry>
                <ns2:zipCode>33134</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>305-599-1800</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>ERNEST N CSISZAR</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Director</relationshipToIssuer>
            </relationshipsToIssuer>
        </issuerInfo>
        <securitiesInformation>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <brokerOrMarketmakerDetails>
                <name>Morgan Stanley Smith Barney LLC Executive Financial Services</name>
                <address>
                    <ns2:street1>1 New York Plaza</ns2:street1>
                    <ns2:street2>8th Floor</ns2:street2>
                    <ns2:city>New York</ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10004</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>4853</noOfUnitsSold>
            <aggregateMarketValue>538480.63</aggregateMarketValue>
            <noOfUnitsOutstanding>79220966</noOfUnitsOutstanding>
            <approxSaleDate>08/22/2024</approxSaleDate>
            <securitiesExchangeName>NYSE</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>05/15/2023</acquiredDate>
            <natureOfAcquisitionTransaction>Compensation for Past Services</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>380</amountOfSecuritiesAcquired>
            <paymentDate>05/15/2023</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>11/13/2020</acquiredDate>
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            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>278</amountOfSecuritiesAcquired>
            <paymentDate>11/13/2020</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>08/15/2019</acquiredDate>
            <natureOfAcquisitionTransaction>Compensation for Past Services</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>304</amountOfSecuritiesAcquired>
            <paymentDate>08/15/2019</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>08/13/2021</acquiredDate>
            <natureOfAcquisitionTransaction>Compensation for Past Services</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>267</amountOfSecuritiesAcquired>
            <paymentDate>08/13/2021</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
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            <acquiredDate>11/15/2021</acquiredDate>
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            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>265</amountOfSecuritiesAcquired>
            <paymentDate>11/15/2021</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>02/15/2023</acquiredDate>
            <natureOfAcquisitionTransaction>Compensation for Past Services</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>370</amountOfSecuritiesAcquired>
            <paymentDate>02/15/2023</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>05/13/2022</acquiredDate>
            <natureOfAcquisitionTransaction>Compensation for Past Services</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>320</amountOfSecuritiesAcquired>
            <paymentDate>05/13/2022</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>08/15/2022</acquiredDate>
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            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>449</amountOfSecuritiesAcquired>
            <paymentDate>08/15/2022</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>08/15/2023</acquiredDate>
            <natureOfAcquisitionTransaction>Compensation for Past Services</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>393</amountOfSecuritiesAcquired>
            <paymentDate>08/15/2023</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>02/14/2020</acquiredDate>
            <natureOfAcquisitionTransaction>Compensation for Past Services</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>411</amountOfSecuritiesAcquired>
            <paymentDate>02/14/2020</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>02/12/2021</acquiredDate>
            <natureOfAcquisitionTransaction>Compensation for Past Services</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>287</amountOfSecuritiesAcquired>
            <paymentDate>02/12/2021</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>11/15/2019</acquiredDate>
            <natureOfAcquisitionTransaction>Compensation for Past Services</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>251</amountOfSecuritiesAcquired>
            <paymentDate>11/15/2019</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>02/15/2022</acquiredDate>
            <natureOfAcquisitionTransaction>Compensation for Past Services</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>268</amountOfSecuritiesAcquired>
            <paymentDate>02/15/2022</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>11/15/2022</acquiredDate>
            <natureOfAcquisitionTransaction>Compensation for Past Services</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>400</amountOfSecuritiesAcquired>
            <paymentDate>11/15/2022</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>05/14/2021</acquiredDate>
            <natureOfAcquisitionTransaction>Compensation for Past Services</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>210</amountOfSecuritiesAcquired>
            <paymentDate>05/14/2021</paymentDate>
            <natureOfPayment>Services Rendered</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>08/22/2024</noticeDate>
            <planAdoptionDates/>
            <signature>/s/ Ernst N Csiszar</signature>
        </noticeSignature>
    </formData>
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[{"type": "144", "sequence": "1", "filename": "primary_doc.xml", "secsgml_size_bytes": 11689}]
144
0001341639
XXXXXXXX
LIVE
0000015615
MASTEC INC.
001-08106
800 S. Douglas Road, 12th Floor
Coral Gables
FL
33134
305-599-1800
ERNEST N CSISZAR
Director
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
4853
538480.63
79220966
08/22/2024
NYSE
Common
05/15/2023
Compensation for Past Services
Issuer
N
380
05/15/2023
Services Rendered
Common
11/13/2020
Compensation for Past Services
Issuer
N
278
11/13/2020
Services Rendered
Common
08/15/2019
Compensation for Past Services
Issuer
N
304
08/15/2019
Services Rendered
Common
08/13/2021
Compensation for Past Services
Issuer
N
267
08/13/2021
Services Rendered
Common
11/15/2021
Compensation for Past Services
Issuer
N
265
11/15/2021
Services Rendered
Common
02/15/2023
Compensation for Past Services
Issuer
N
370
02/15/2023
Services Rendered
Common
05/13/2022
Compensation for Past Services
Issuer
N
320
05/13/2022
Services Rendered
Common
08/15/2022
Compensation for Past Services
Issuer
N
449
08/15/2022
Services Rendered
Common
08/15/2023
Compensation for Past Services
Issuer
N
393
08/15/2023
Services Rendered
Common
02/14/2020
Compensation for Past Services
Issuer
N
411
02/14/2020
Services Rendered
Common
02/12/2021
Compensation for Past Services
Issuer
N
287
02/12/2021
Services Rendered
Common
11/15/2019
Compensation for Past Services
Issuer
N
251
11/15/2019
Services Rendered
Common
02/15/2022
Compensation for Past Services
Issuer
N
268
02/15/2022
Services Rendered
Common
11/15/2022
Compensation for Past Services
Issuer
N
400
11/15/2022
Services Rendered
Common
05/14/2021
Compensation for Past Services
Issuer
N
210
05/14/2021
Services Rendered
Y
08/22/2024
/s/ Ernst N Csiszar