T-Mobile today joined the acquisition fray, announcing it has agreed to acquire regional GSM provider SunCom Wireless for $2.4 billion.

With AT&T acquiring Dobson Communications, Sprint buying up its CDMA affiliates, and Leap Wireless and MetroPCS in contentious merger discussions, the regional carrier space is rapidly consolidating. T-Mobile, as the smallest of the nationwide carriers, has stayed out of the market and in fact has been the subject of acquisition speculation in its own right. But parent company Deutsche Telekom has said it is not interested in selling the operator and shored up its commitment to the U.S. operator by investing in AWS spectrum last year and spending $2.6 billion on its planned UMTS network.

The deal involves a cash payment of $1.6 billion to SunCom Wireless Holdings’ shareholders and Deutsche Telekom’s assumption of $800 million in SunCom debt. T-Mobile has worked with SunCom since 2004 when the two entered into a roaming agreement with the carrier for its networks in North Carolina, South Carolina, Tennessee, Georgia, Puerto Rico and the U.S. Virgin Islands.

The acquisition will add 1.14 million subscribers to T-Mobile’s 27 million-strong subscriber base, giving it a substantial size boost but still far distant to the big three providers Verizon Wireless, AT&T and Sprint. T-Mobile CEO Robert Dotson said that SunCom’s footprint meshes perfectly with T-Mobile as exemplified by their long-standing roaming agreement. The combined GSM/EDGE networks will increased T-Mobile’s coverage by an additional 15 million people in the Southeast, and give T-Mobile a presence in 98 of the top 100 markets.