T-Mobile has been testing a prepaid MVNO named GoSmart in a limited number of markets, and according to FierceWireless, the carrier plans to expand the service nationwide in February. There's no official word on nationwide pricing, but GoSmart currently features three monthly service tiers: a $30 plan with unlimited voice and text messaging, a $35 plan with the same plus unlimited web browsing, and a $45 plan with unlimited voice, text, and up to 5GB of 3G data. Existing customers have a choice between a low-end Alcatel feature phone, or a SIM kit that can be used with an unlocked GSM device.

T-Mobile's move into the prepaid market follows close competitor Sprint, which offers prepaid plans at similar price points through its MVNOs, including Virgin Mobile and Boost Mobile. Sprint also launched its own branded prepaid service on January 25th called "Sprint As You Go," which is a pricier offering starting at $50 a month.