Skype's popular telephony application will be available on nine phone models sold by Verizon Wireless starting on Thursday.
The venture of Verizon Communications and Vodafone Group Plc said it would eventually offer Skype on other smartphones, but would first concentrate on Research In Motion's BlackBerry devices and phones running Google Inc's Android software system.
The Skype Mobile application, which Skype worked closely with Verizon to develop, will allow Verizon's data subscribers to exchange phone calls with other Skype members at no extra cost. This means Verizon Wireless may lose revenue from long distance calls, but it said this would not be material.
The No. 1 U.S. mobile service expects Skype to attract a big enough number of new data subscribers to Verizon that it will offset any revenue declines.
We believe it will be sizable, Jennifer Byrne, Verizon Wireless' director of new business development, said, referring to the takeup of Skype after a press conference at the CTIA telecoms conference in Las Vegas, where Verizon Wireless and Skype discussed their plans.
In a departure for Skype, Verizon Wireless will connect Skype users on its traditional voice network instead of over the Internet, which is where Skype has traditionally routed calls in order to reduce fees to consumers.
Skype mobile executive Russ Shaw said the company decided to use the Verizon Wireless network in order to get better-quality service than its Internet offering.
Verizon Wireless said it may eventually deliver Skype calls over the Internet when it launches a higher speed network, but had no plans to do so yet.
The companies said that while other operators can offer a version of Skype, no other operator would be able to offer the Skype mobile app that Verizon will.
Skype's free calls over the Internet between computers has grown in popularity. It has added some 520 million registered users around the globe since it was founded in 2002.
But until now, it has found little traction on wireless devices since most telecoms operators see it as a risk to their core phone call business.
(Reporting by Sinead Carew; Editing by Richard Chang)