Commitments and Contingencies	6 Months Ended
Jun. 30, 2025
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies MasTec is subject to a variety of legal cases, claims and other disputes that arise from time to time in the ordinary course of its business, including project contract price and other project disputes, other project-related liabilities and acquisition purchase price disputes. MasTec cannot provide assurance that it will be successful in recovering all or any of the potential damages it has claimed or in defending claims against the Company. The outcome of such cases, claims and disputes cannot be predicted with certainty and an unfavorable resolution of one or more of them could have a material adverse effect on the Company’s business, financial condition, results of operations and cash flows. Acquired Legacy Solar Matter See Note 14 – Commitments and Contingencies contained within the Company’s audited consolidated financial statements filed with its 2024 Form 10-K for additional information regarding the acquired legacy solar matter, with respect to which, in January 2025, the parties agreed to a negotiated settlement and mutual releases in exchange for the payment to the plaintiffs by Infrastructure and Energy Alternatives, Inc. (“IEA”) and its subsidiary, IEA Constructors, LLC, of an immaterial amount of cash. There have been no material developments since the filing of such Form 10-K. Other Commitments and Contingencies Leases. In the ordinary course of business, the Company enters into non-cancelable operating leases for certain of its facility, vehicle and equipment needs, including certain related party leases. See Note 7 – Lease Obligations and Note 13 – Related Party Transactions. Letters of Credit. In the ordinary course of business, the Company is required to post letters of credit for its insurance carriers and surety bond providers and in support of performance under certain contracts as well as certain obligations associated with the Company’s equity investments and other strategic arrangements, including its variable interest entities. In addition, from time to time, certain customers require the Company to post letters of credit to ensure payment of subcontractors and vendors, and guarantee performance under contracts. Such letters of credit are generally issued by a bank or similar financial institution. The letter of credit commits the issuer to pay specified amounts to the holder of the letter of credit under certain conditions. If this were to occur, the Company would be required to reimburse the issuer of the letter of credit, which, depending upon the circumstances, could result in a charge to earnings. As of June 30, 2025 and December 31, 2024, there were $53.6 million and $81.7 million, respectively, of letters of credit issued under the Company’s credit facilities. Letter of credit claims have historically not been material. The Company is not aware of any material claims relating to its outstanding letters of credit as of June 30, 2025 or December 31, 2024. Performance and Payment Bonds. In the ordinary course of business, MasTec is required by certain customers to provide performance and payment bonds for contractual commitments related to its projects. These bonds provide a guarantee to the customer that the Company will perform under the terms of a contract and that the Company will pay its subcontractors and vendors. If the Company fails to perform under a contract or to pay its subcontractors and vendors, the customer may demand that the surety make payments or provide services under the bond. The Company must reimburse the surety for expenses or outlays it incurs. As of June 30, 2025 and December 31, 2024, outstanding performance and payment bonds approximated $8.5 billion and $7.6 billion, respectively, and estimated costs to complete projects secured by these bonds totaled $2.6 billion and $2.2 billion, respectively. Included in these balances as of June 30, 2025 and December 31, 2024 are $1,255.1 million and $838.7 million, respectively, of outstanding performance and payment bonds issued on behalf of the Company’s proportionately consolidated non-controlled contractual joint ventures, representing the Company’s proportionate share of the total bond obligation for the related projects. Investment and Strategic Arrangements. The Company holds undivided interests, ranging from 85% to 90%, in multiple proportionately consolidated non-controlled contractual joint ventures that provide infrastructure construction services for electrical transmission projects, as well as undivided interests, ranging from 25% to 50%, in each of five civil construction projects. Income and/or loss incurred by these joint ventures is generally shared proportionally by the respective joint venture members, with the members of the joint ventures jointly and severally liable for all of the obligations of the joint venture. The respective joint venture agreements provide that each joint venture partner indemnify the other party for any liabilities incurred by such joint venture in excess of its ratable portion of such liabilities. Thus, it is possible that the Company could be required to pay or perform obligations in excess of its share if the other joint venture partners fail or refuse to pay or perform their respective share of the obligations. As of June 30, 2025, the Company was not aware of material claims against it in connection with these arrangements. Included in the Company’s cash balances as of June 30, 2025 and December 31, 2024 are amounts held by entities that are proportionately consolidated totaling $37.8 million and $46.7 million, respectively. These amounts are available to support the operations of those entities, but are not available for the Company’s other operations. The Company has other investment and strategic arrangements, under which it may incur costs or provide financing, performance, financial and/or other guarantees. See Note 4 – Fair Value of Financial Instruments and Note 13 – Related Party Transactions for additional information pertaining to the Company’s investment and strategic arrangements. Self-Insurance. MasTec maintains insurance policies for workers’ compensation, general liability and automobile liability, which are subject to per claim deductibles. The Company is self-insured up to the amount of the deductible. The Company also maintains excess umbrella coverage. The Company manages certain of its insurance liabilities indirectly through its wholly-owned captive insurance company, which reimburses claims up to the applicable insurance limits. Captive insurance-related cash balances totaled approximately $3.2 million and $2.2 million as of June 30, 2025 and December 31, 2024, respectively, which amounts are generally not available for use in the Company’s other operations. As of June 30, 2025 and December 31, 2024, MasTec’s estimated gross liability for unpaid claims and associated expenses, including incurred but not reported losses related to these policies, totaled $275.7 million and $251.0 million, respectively, of which $202.0 million and $184.1 million was reflected within other long-term liabilities, with the remainder reflected within other accrued expenses, in the consolidated balance sheets as of the respective periods. Related insurance recoveries/receivables totaled $26.0 million and $24.4 million as of June 30, 2025 and December 31, 2024, respectively, of which $22.7 million and $21.4 million was reflected within other long-term assets, with the remainder reflected within other current assets, in the consolidated balance sheets as of the respective periods. MasTec also maintains an insurance policy with respect to employee group medical claims, which is subject to annual per employee maximum losses. MasTec’s estimated liability for employee group medical claims totaled $4.1 million and $4.7 million as of June 30, 2025 and December 31, 2024, respectively. The Company is required to post collateral, generally in the form of letters of credit, surety bonds and cash to certain of its insurance carriers. Insurance-related letters of credit for the Company’s workers’ compensation, general liability and automobile liability policies amounted to $7.5 million and $8.7 million as of June 30, 2025 and December 31, 2024, respectively. Outstanding surety bonds related to self-insurance programs amounted to $193.7 million and $196.3 million as of June 30, 2025 and December 31, 2024, respectively. Collective Bargaining Agreements and Multiemployer Plans. In connection with the IEA acquisition, the Company assumed a multiemployer pension plan withdrawal liability (the “IEA withdrawal liability”), under which IEA was obligated to make monthly payments of approximately $10,000. In January 2025, the Company settled its IEA withdrawal liability by issuing a lump-sum payment for the remaining obligation of $1.3 million. See Note 14 – Commitments and Contingencies contained within the Company’s audited consolidated financial statements filed with its 2024 Form 10-K for additional information regarding the Company’s multiemployer pension plans. Indemnities. The Company generally indemnifies its customers for the services it provides under its contracts, as well as other specified liabilities, which may subject the Company to indemnity claims, liabilities and related litigation. As of both June 30, 2025 and December 31, 2024, the Company had accrued project close-out liabilities of approximately $20 million. The Company is not aware of any other material asserted or unasserted claims in connection with its potential indemnity obligations. Other Guarantees. From time to time in the ordinary course of its business, MasTec guarantees the obligations of its subsidiaries, including obligations under certain contracts with customers, certain lease obligations, and in some states, obligations in connection with obtaining contractors’ licenses. MasTec has also issued performance and other guarantees in connection with certain of its equity investments. MasTec also generally warrants the work it performs following substantial completion of a project. Much of the work performed by the Company is evaluated for defects shortly after the work is completed. If warranty claims occur, the Company could be required to repair or replace warrantied items, or, if customers elect to repair or replace the warrantied item using the services of another provider, the Company could be required to pay for the cost of the repair or replacement. Warranty claims have historically not been material. Concentrations of Risk. The Company had approximately 1,365 customers for the six months ended June 30, 2025. As of both June 30, 2025 and December 31, 2024, no customer represented greater than 10% of the Company’s consolidated net accounts receivable position, which is calculated as accounts receivable, net, less deferred revenue. The Company derived approximately 36% of its revenue from its top ten customers for both the three months ended June 30, 2025 and 2024, and derived approximately 35% and 39% of such revenue for the six months ended June 30, 2025 and 2024, respectively.

MasTec is subject to a variety of legal cases, claims and other disputes that arise from time to time in the ordinary course of its business, including project contract price and other project disputes, other project-related liabilities and acquisition purchase price disputes. MasTec cannot provide assurance that it will be successful in recovering all or any of the potential damages it has claimed or in defending claims against the Company. The outcome of such cases, claims and disputes cannot be predicted with certainty and an unfavorable resolution of one or more of them could have a material adverse effect on the Company’s business, financial condition, results of operations and cash flows.

See Note 14 – Commitments and Contingencies contained within the Company’s audited consolidated financial statements filed with its 2024 Form 10-K for additional information regarding the acquired legacy solar matter, with respect to which, in January 2025, the parties agreed to a negotiated settlement and mutual releases in exchange for the payment to the plaintiffs by Infrastructure and Energy Alternatives, Inc. (“IEA”) and its subsidiary, IEA Constructors, LLC, of an immaterial amount of cash. There have been no material developments since the filing of such Form 10-K.

Letters of Credit. In the ordinary course of business, the Company is required to post letters of credit for its insurance carriers and surety bond providers and in support of performance under certain contracts as well as certain obligations associated with the Company’s equity investments and other strategic arrangements, including its variable interest entities. In addition, from time to time, certain customers require the Company to post letters of credit to ensure payment of subcontractors and vendors, and guarantee performance under contracts. Such letters of credit

are generally issued by a bank or similar financial institution. The letter of credit commits the issuer to pay specified amounts to the holder of the letter of credit under certain conditions. If this were to occur, the Company would be required to reimburse the issuer of the letter of credit, which, depending upon the circumstances, could result in a charge to earnings. As of June 30, 2025 and December 31, 2024, there were $53.6 million and $81.7 million, respectively, of letters of credit issued under the Company’s credit facilities. Letter of credit claims have historically not been material. The Company is not aware of any material claims relating to its outstanding letters of credit as of June 30, 2025 or December 31, 2024.

Performance and Payment Bonds. In the ordinary course of business, MasTec is required by certain customers to provide performance and payment bonds for contractual commitments related to its projects. These bonds provide a guarantee to the customer that the Company will perform under the terms of a contract and that the Company will pay its subcontractors and vendors. If the Company fails to perform under a contract or to pay its subcontractors and vendors, the customer may demand that the surety make payments or provide services under the bond. The Company must reimburse the surety for expenses or outlays it incurs. As of June 30, 2025 and December 31, 2024, outstanding performance and payment bonds approximated $8.5 billion and $7.6 billion, respectively, and estimated costs to complete projects secured by these bonds totaled $2.6 billion and $2.2 billion, respectively. Included in these balances as of June 30, 2025 and December 31, 2024 are $1,255.1 million and $838.7 million, respectively, of outstanding performance and payment bonds issued on behalf of the Company’s proportionately consolidated non-controlled contractual joint ventures, representing the Company’s proportionate share of the total bond obligation for the related projects.

Investment and Strategic Arrangements. The Company holds undivided interests, ranging from 85% to 90%, in multiple proportionately consolidated non-controlled contractual joint ventures that provide infrastructure construction services for electrical transmission projects, as well as undivided interests, ranging from 25% to 50%, in each of five civil construction projects. Income and/or loss incurred by these joint ventures is generally shared proportionally by the respective joint venture members, with the members of the joint ventures jointly and severally liable for all of the obligations of the joint venture. The respective joint venture agreements provide that each joint venture partner indemnify the other party for any liabilities incurred by such joint venture in excess of its ratable portion of such liabilities. Thus, it is possible that the Company could be required to pay or perform obligations in excess of its share if the other joint venture partners fail or refuse to pay or perform their respective share of the obligations. As of June 30, 2025, the Company was not aware of material claims against it in connection with these arrangements. Included in the Company’s cash balances as of June 30, 2025 and December 31, 2024 are amounts held by entities that are proportionately consolidated totaling $37.8 million and $46.7 million, respectively. These amounts are available to support the operations of those entities, but are not available for the Company’s other operations.

The Company has other investment and strategic arrangements, under which it may incur costs or provide financing, performance, financial and/or other guarantees. See Note 4 – Fair Value of Financial Instruments and Note 13 – Related Party Transactions for additional information pertaining to the Company’s investment and strategic arrangements.

Self-Insurance. MasTec maintains insurance policies for workers’ compensation, general liability and automobile liability, which are subject to per claim deductibles. The Company is self-insured up to the amount of the deductible. The Company also maintains excess umbrella coverage. The Company manages certain of its insurance liabilities indirectly through its wholly-owned captive insurance company, which reimburses claims up to the applicable insurance limits. Captive insurance-related cash balances totaled approximately $3.2 million and $2.2 million as of June 30, 2025 and December 31, 2024, respectively, which amounts are generally not available for use in the Company’s other operations.

As of June 30, 2025 and December 31, 2024, MasTec’s estimated gross liability for unpaid claims and associated expenses, including incurred but not reported losses related to these policies, totaled $275.7 million and $251.0 million, respectively, of which $202.0 million and $184.1 million was reflected within other long-term liabilities, with the remainder reflected within other accrued expenses, in the consolidated balance sheets as of the respective periods. Related insurance recoveries/receivables totaled $26.0 million and $24.4 million as of June 30, 2025 and December 31, 2024, respectively, of which $22.7 million and $21.4 million was reflected within other long-term assets, with the remainder reflected within other current assets, in the consolidated balance sheets as of the respective periods.

MasTec also maintains an insurance policy with respect to employee group medical claims, which is subject to annual per employee maximum losses. MasTec’s estimated liability for employee group medical claims totaled $4.1 million and $4.7 million as of June 30, 2025 and December 31, 2024, respectively.

The Company is required to post collateral, generally in the form of letters of credit, surety bonds and cash to certain of its insurance carriers. Insurance-related letters of credit for the Company’s workers’ compensation, general liability and automobile liability policies amounted to $7.5 million and $8.7 million as of June 30, 2025 and December 31, 2024, respectively. Outstanding surety bonds related to self-insurance programs amounted to $193.7 million and $196.3 million as of June 30, 2025 and December 31, 2024, respectively.

Collective Bargaining Agreements and Multiemployer Plans. In connection with the IEA acquisition, the Company assumed a multiemployer pension plan withdrawal liability (the “IEA withdrawal liability”), under which IEA was obligated to make monthly payments of approximately $10,000. In January 2025, the Company settled its IEA withdrawal liability by issuing a lump-sum payment for the remaining obligation of $1.3 million. See Note 14 – Commitments and Contingencies contained within the Company’s audited consolidated financial statements filed with its 2024 Form 10-K for additional information regarding the Company’s multiemployer pension plans.

Indemnities. The Company generally indemnifies its customers for the services it provides under its contracts, as well as other specified liabilities, which may subject the Company to indemnity claims, liabilities and related litigation. As of both June 30, 2025 and December 31, 2024, the Company had accrued project close-out liabilities of approximately $20 million. The Company is not aware of any other material asserted or unasserted claims in connection with its potential indemnity obligations.

Other Guarantees. From time to time in the ordinary course of its business, MasTec guarantees the obligations of its subsidiaries, including obligations under certain contracts with customers, certain lease obligations, and in some states, obligations in connection with obtaining contractors’ licenses. MasTec has also issued performance and other guarantees in connection with certain of its equity investments. MasTec also generally warrants the work it performs following substantial completion of a project. Much of the work performed by the Company is evaluated for defects shortly after the work is completed. If warranty claims occur, the Company could be required to repair or replace warrantied items, or, if

Concentrations of Risk. The Company had approximately 1,365 customers for the six months ended June 30, 2025. As of both June 30, 2025 and December 31, 2024, no customer represented greater than 10% of the Company’s consolidated net accounts receivable position, which is calculated as accounts receivable, net, less deferred revenue. The Company derived approximately 36% of its revenue from its top ten customers for both the three months ended June 30, 2025 and 2024, and derived approximately 35% and 39% of such revenue for the six months ended June 30, 2025 and 2024, respectively.