MASTEC INC

During the three months ended June 30, 2026, except as provided below, no director or officer (as defined in Rule 16a-1(f) of the Exchange Act)adopted, modified orterminated a contract, instruction or written plan for the purchase or sale of our securities that was intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) or a “non-Rule 10b5-1 trading arrangement,” as defined in Item 408(c) of Regulation S-K.

(1)On May 18, 2026, T. Michael Love, Chief Accounting Officer, adopted a Rule 10b5-1 sell-to-cover instruction plan that provides for the sale of shares of common stock necessary to satisfy tax withholding obligations arising exclusively from the vesting of shares of restricted stock on November 1, 2026, and the vesting of future awards not yet granted. The total number of shares of common stock that may be sold pursuant to the sell-to-cover instruction plan is not determinable as it will depend on the number of shares that vest and applicable tax withholding requirements. The sell-to-cover instruction plan will remain in effect indefinitely unless earlier terminated.

(2)On June 5, 2026, Robert Apple, Chief Operating Officer, terminated a Rule 10b5-1 plan, which was previously adopted on March 13, 2026. The terminated trading plan provided for the potential sale of up to 30,079 shares of our common stock, and was scheduled to be effective from June 12, 2026 until December 31, 2027.