Together the deal means access to around 1 billion users
Skype is integrating with Facebook to make it easier to call and video chat with friends and family on the social network.
The deal comes amid fevered rumours that Facebook plans to launch a phone of its own.
Meanwhile Skype is gearing up for a $100m (£62m) share issue.
"The essence of the Skype experience is communicating with the people you care about," said Rick Osterloh, Skype's head of consumer products.
The new Skype for Windows will include a Facebook tab. This means that for the first time Skype users can keep up-to-date and interact with their Facebook news feed including posting status updates, commenting and liking directly from Skype
