As customers ditch their landline phones in droves, T-Mobile USA has decided to enter the wireline voice business for the first time.

Its new HotSpot @Home Talk Forever Home Phone announced today will offer customers unlimited calls for $10 a month, plus the initial $50 cost of the special router required for the service. Customers must also be T-Mobile subscribers with a mobile plan of at least $39.99 a month and must also have a broadband connection at home.

In other words, it's an Internet-based calling service, similar to what Vonage Holdings Corp. offers, except this one is bundled to an existing mobile phone account.

T-Mobile acknowledges that wireline voice is a declining business but says that not everyone who has a mobile phone is ready to get rid of the traditional home phone.

"This is an opportunity for T-Mobile to deliver great value to customers and further displace traditional landline phone service," says a company spokeswoman.

Despite the nationwide decrease in landline phone use, T-Mobile's plans could prove to be an attractive option for those who still want to keep their home phones for a much lower price. "We believe this is a service that will appeal to families looking to save money without sacrificing," says the spokeswoman.

T-Mobile's new service comes on the heels of its HotSpot@Home announcement from the summer. That service, also available for $10 a month, allows subscribers to make unlimited calls from their mobile phones using a WiFi connection in the home. (See T-Mobile Launches UMA in USA.)

— Raymond McConville, Reporter, Light Reading