T-Mobile USA is doing a trial run of a new $79.99 unlimited data plan which offers customers more voice minutes than its current unlimited data plan at the same price point.

The company's new EvenMore plan will only be available for a limited time and provides unlimited text and data and 1,500 voice minutes.

The plan offers customers more voice minutes than T-Mobile's other $79.99 unlimited text and data plan, which includes just 500 voice minutes, and is a better value for customers than T-Mobile's $89.99 unlimited text and data plan with 1,000 voice minutes.

T-Mobile's plans are priced to compete with similar offers at Sprint, Verizon and AT&T, whose comparable service plans are more expensive than T-Mobile's, BTIG analyst Walter Piecyk wrote in a recent blog post.

"That amount of minutes is more than most people need and it protects the company from the extreme users," Piecyk wrote.

The trial $80 plan from T-Mobile could mean the carrier has held off on a rumored move to introduce new unlimited rate plans. T-Mobile is fighting to retain customers with competitively-priced plans and a bevy of new phones using its HSPA+ network, which it's marketing as 4G. Deutsche Telekom, T-Mobile's parent company, reports its fourth-quarter earnings tomorrow.