(Reuters) - T-Mobile US Inc's (O:TMUS) quarterly profit jumped nearly sevenfold as the No. 3 U.S. wireless carrier added subscribers and recorded a $2.2 billion gain from recent changes in U.S. tax laws.
The company said it added 891,000 phone subscribers in the fourth quarter, compared with 933,000 a year earlier.
T-Mobile has been using lower prices and added perks to take market share from larger rivals Verizon Communications Inc (N:VZ) and AT&T Inc (N:T) in a saturated market for wireless services.
In 2018, T-Mobile said it expects to add between 2 million and 3 million subscribers who pay a monthly bill. Analysts at JPMorgan (NYSE:JPM) said in a note the numbers were in line with their estimates.
Shares were down 0.2 percent at $61.95 in premarket trading.
T-Mobile's net income was $2.71 billion, or $3.11 per share, in the quarter ended Dec. 31, up from $390 million, or 45 cents a share, a year earlier.
Excluding items, the company earned 48 cents per share.
Revenue rose 5.1 percent to $10.76 billion. Analysts, on average, were expecting revenue of $10.83 billion, according to Thomson Reuters I/B/E/S.
Last month, the wireless carrier said it had closed on its acquisition of Layer3 TV, a startup that has marketed itself as a next-generation cable service, for an undisclosed amount. It has plans to launch a new streaming service this year.