US number-four operator T-Mobile USA launched the GoSmart prepaid mobile brand which it hopes will help it regain customers lost to rivals.

The GoSmart devices and services were made available at more than 3,000 reseller stores yesterday with services starting at $30 per month for unlimited talk time and text message, but no mobile internet. Customers are not tied into an annual contract.

A $35 plan adds internet access on T-Mobile’s slower data network with another $10 per month providing access to faster mobile data speeds.

The T-Mobile-branded prepaid services offer 5GB of data services per month on the faster service, in addition to 100 minutes of voice calls and unlimited texting. However, these services are more expensive and T-Mobile hopes the GoSmart brand will attract consumers more interested in using their phone for voice calls than for data and looking for lower costs.

Reuters reports that the company has been testing the prepaid service in nine markets since December and claims to have already signed up tens of thousands of customers.

Senior VP of marketing for GoSmart, Doug Chartier, cited forecasts that suggest the prepaid market could grow at a rate of 7-8 per cent annually, with 80 million US consumers currently opting for prepaid phones.

T-Mobile parent Deutsche Telekom has been looking to strengthen its US unit for some time in an attempt to keep pace with larger rivals. A US$39 billion merger with AT&T was called off last year following regulatory objections.

T-Mobile agreed a merger with prepaid rival MetroPCS in October although some shareholders have registered their opposition to the deal.