T-Mobile USA plans to launch nationwide a new service that lets customers place unlimited domestic VoIP calls from their home landline phones. Called T-Mobile @Home, the service, which has been tested in Seattle and Dallas since February, will cost $10 per month and is expected to roll out July 2.

The service will be available to customers with a T-Mobile wireless plan of at least $40 per month. In order to access service, customers will need to buy a T-Mobile Internet router, which plugs into a home broadband connection. Customers can then plug a standard landline telephone into the router. The T-Mobile router costs $50, and customers can keep their home phone numbers.

Unlike other major U.S. wireless carriers that have launched similar services such as AT&T and Verizon, T-Mobile doesn’t have an established landline business.

T-Mobile already launched an at-home service earlier this year, called HotSpot@Home. The service allows Wi-Fi-enabled handsets to connect to a wireless router at home, or any T-Mobile hotspot, for unlimited wireless VoIP calling.