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Contact : J. Marc Lewis , Vice President - Investor Relations 305-406-1815 305-406-1886 fax marc.lewis@mastec.com Exhibit 99.1 MasTec 800 S. Douglas Road , 12th Floor Coral Gables , Florida 33134 Tel : 305-599-1800 Fax : 305-406-1960 www.mastec.com For Immediate Release MasTec Announces Record First Quarter 2021 Results and Increased Annual Guidance First Quarter 2021 Results Include GAAP Net Income of $ 66.1 Million , Adjusted EBITDA of $ 204 Million , Diluted Earnings Per Share of $ 0.89 , and Adjusted Diluted Earnings Per Share of $ 1.10 , with All Key Metrics Representing Record Levels Record First Quarter Revenue of $ 1.8 Billion and Cash Flow from Operations of $ 257 Million Continued Strong Balance Sheet as of March 31 , 2021 , Comfortable Leverage Metrics and Record Liquidity of Approximately $ 1.7 Billion Increasing 2021 Annual Guidance for Revenue , Diluted Earnings Per Share , Adjusted EBITDA and Adjusted Diluted Earnings Per Share Coral Gables , FL ( May 6 , 2021 ) — MasTec , Inc. ( NYSE : MTZ ) today announced record first quarter 2021 financial results and increased its guidance for the remainder of 2021 . First quarter 2021 revenue was $ 1.8 billion , compared to $ 1.4 billion for the prior year , a 25 % increase . First quarter 2021 cash flow from operations was $ 257 million , compared to $ 203 million for the prior year , a 27 % increase . First quarter 2021 GAAP net income was $ 66.1 million , or $ 0.89 per diluted share , compared to $ 36.1 million , or $ 0.48 per diluted share in the prior year . These metrics all represented record first quarter performance levels . Record first quarter 2021 adjusted net income and adjusted diluted earnings per share , both non - GAAP measures , were $ 82.0 million , and $ 1.10 , respectively . First quarter 2021 adjusted EBITDA , also a non - GAAP measure , was $ 204 million , or 11.5 % of revenue , a 320 - basis point improvement when compared to the prior year . 18 - month backlog as of March 31 , 2021 was $ 7.9 billion , equal to the fourth quarter 2020 level . The Company is increasing annual 2021 guidance expectations based on strong first quarter results and the expected partial year benefit of the recently announced INTREN acquisition . Based on the information available today , the Company estimates annual 2021 revenue of approximately $ 8.2 billion , a $ 400 million increase over prior guidance . Annual 2021 GAAP net income and diluted earnings per share are expected to approximate $ 322 million and $ 4.35 , respectively . Annual 2021 adjusted EBITDA , a non - GAAP measure , is expected to be $ 930 million , and annual 2021 adjusted diluted earnings per share , a non - GAAP measure , is expected to be $ 5.40 , a $ 0.40 increase over prior guidance .