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T Industry - Leading Customer Growth T - Mobile Raises 2021 Guidance as Network Leadership Fuels Industry - Leading Growth with Strong First Quarter 2021 Results Strong Financial Results Drive Guidance Raise ● Total net additions of 1.4 million , best in industry Postpaid net additions of 1.2 million , best in industry and raising 2021 guidance Postpaid phone net additions of 773 thousand , best in industry ● ( 1 ) Raising 2021 Merger Synergies Guidance on Continued Integration Progress Expect Merger synergies of $ 2.8 billion to $ 3.1 billion Approximately 50 percent of Sprint customer traffic is now carried on the T - Mobile network , 2x more than last quarter EXHIBIT 99.1 Total revenues of $ 19.8 billion and service revenues of $ 14.2 billion Net income of $ 933 million , diluted earnings per share ( “ EPS ” ) of $ 0.74 and Adjusted EBITDA ( ¹ ) of $ 6.9 billion Core Adjusted EBITDA ( ¹ ) of $ 5.9 billion , raising 2021 guidance Net cash provided by operating activities of $ 3.7 billion and Free Cash Flow ( ¹ ) of $ 1.3 billion , raising 2021 guidance Approximately 20 percent of Sprint customers have been moved to the T - Mobile network America's Largest , Fastest and Most Reliable 5G Network Extends its Lead Extended Range 5G covers 295 million people across 1.6 million square miles , 4x more than Verizon and 2x more than AT & T Ultra Capacity 5G covers 140 million people and on track to cover 200 million people nationwide by the end of 2021 Majority of independent third - party network benchmarking reports show T - Mobile as the clear leader in 5G speed and availability Network perception catching up to reality with a nearly 120 percent increase in consumers who view T - Mobile as " The 5G Company " since Q3 2019 BELLEVUE , Wash . - May 4 , 2021 - T - Mobile US , Inc. ( NASDAQ : TMUS ) reported first quarter 2021 results today , highlighted by industry - leading total net additions , postpaid net additions , and postpaid phone net additions . The company also reported strong financial results and raised 2021 guidance as its synergy - backed model simultaneously delivers customer growth and profitability . " T - Mobile puts customers at the center of everything we do by giving them the best network , value and experience all at once - and this quarter's stellar , industry - leading results prove that they're noticing , " said Mike Sievert , CEO of T Mobile . " We just keep pushing further ahead of the competition . Our network leadership is fueling customer momentum , delivering merger synergies and expanding our addressable markets for growth . We have so much confidence that we are raising 2021 guidance just one quarter into the year . Our mission is to be the very best at connecting customers to their world and we're delivering on it . " Adjusted EBITDA , Core Adjusted EBITDA and Free Cash Flow are non - GAAP financial measures . These non - GAAP financial measures should be considered in addition to , but not as a substitute for , the information provided in accordance with GAAP . Reconciliations for these non - GAAP financial measures to the most directly comparable GAAP financial measures are provided in the Reconciliation of Non - GAAP Financial Measures to GAAP Financial Measures tables . We are not able to forecast Net income on a forward - looking basis without unreasonable efforts due to the high variability and difficulty in predicting certain items that affect Net income including , but not limited to , Income tax expense , stock - based compensation expense and Interest expense . Adjusted EBITDA and Core Adjusted EBITDA should not be used to predict Net income as the difference between either of the two measures and Net Income is variable . 1 Q1 2021