T-Mobile US adds record 552,000 postpaid customers in August

(Adds CEO quote, details, background throughout)

By Marina Lopes

WASHINGTON, Sept 12 (Reuters) - T-Mobile US added 552,000 postpaid customers in August, more customer additions than any other month in the history of the company, Chief Executive John Legere told investors at a conference in New York on Friday.

The fourth largest U.S. wireless carrier also added 208,000 pre-paid customers in August. Valuable postpaid customers pay for their service after usage, while pre-paid customers pay in advance.

The company has turned around years of subscriber losses through aggressive promotions in the past year and a half. The wave of new subscribers was in part due to the popularity of a promotion that allows customers to add four lines for $100 a month, according to Legere.

"The company is on fire," he said.

The carrier added a total of 2.75 million customers in August, the largest number of monthly subscriber additions in its history, it announced at a company event on Wednesday.

Legere also said that the ratio of subscribers moving from rival Sprint Corp to T-Mobile was 17 to 1 at the height of T-Mobile's Contract Freedom campaign, a promotion launched in January, whereby the company pays early termination fees for subscribers who switch to its network.

The ratio of customers moving from Sprint to T-Mobile is now around 2.3 to 1, Legere said.

In August, T-Mobile rejected a $15 billion bid by France's Iliad (Paris: FR0004035913 - news) as too low. Shortly thereafter, Sprint's $40 billion bid for T-Mobile unraveled under resistance from U.S. regulators who expressed the desire to maintain four competitors in the marketplace.

Multiple companies are still interested in T-Mobile US, Legere said, but he declined to be more specific.

"For now the thought process for us is that we are in a position of strength," he said. "We are a company that has a viable standalone path but a brand and capability that people are interested in." (Reporting by Marina Lopes; editing by Chizu Nomiyama and G Crosse)