AT&T bought Centennial Communications Corp for $944 million today in order improve AT&T’s coverage in the Midwest, Southeast, and Puerto Rico.

The purchase will add 1.1 million customers to AT&T’s 74.9 million base. The move follows Verizon’s purchase of Alltel last week.

Mobile providers are facing a plateau in subscribers due partially to the economic downturn. By purchasing smaller carriers for what amounts to considerably less than it would install cells and repeaters in the same areas, carriers are gaining paid subscribers without much investment. By grabbing midwestern and southern subscribers, both Verizon and AT&T are rolling out new network without installing hardware.

Centennial subscribers should be unaffected although they should move to AT&T’s billing system over time.
via Bloomberg