Skype today unveiled a new North American calling plan, designed to let U.S. and Canadian customers buy a year-long subscription to unlimited voice-over-IP calls to anyone within those two countries.

Skype Unlimited Calling will cost $29.95 a year, although an introductory offer of $14.95 per year is available until Jan. 31. The calls can go anywhere--not just to those on Skype’s peer-to-peer network--and will make the Internet calling service more of a competitor to Vonage, SunRocket, other VoIP plans and even other low-cost calling options.

The plan follows six months of free Skype Out calling for the North American market, which Skype officials say succeeded in boosting the number of registered users and the calling minutes. The company has been trying to gain a larger share of the North American VoIP market. Skype’s free PC-to-PC calling service is already hugely popular internationally.

The Unlimited Calling option is an alternative to buying Skype Out time in $10 prepaid segments.

“The new Skype Unlimited Calling Plan is an affordable option that will save consumers and small businesses hundreds of dollars compared to high rates charged by traditional phone companies,” said Don Albert, vice president and general manager for Skype North America, in a prepared statement. “We want to give Skype customers convenient options of choosing either an unlimited calling plan with a flat annual rate and or staying with our standard pay-per-minute offering.”

As an additional incentive to customers to sign up early, Skype is offering $100 in Skype Out credit for international calls and $50 in discount coupons toward buying Skype-related hardware, such as ATA devices.