Microsoft has announced it will retire Windows Live Messenger in favour of Skype.
A blog post revealed the instant messaging tool will be shut down during the first quarter of 2013, in all countries except mainland China. It is not currently known how long the Chinese service will live on for.
The news comes a year-and-a-half after Microsoft purchased Skype for $8.5 billion (£5 billion).
Late October's release of Skype 6.0 for Windows and Mac, in which users can sign in to Skype through a Microsoft account and simultaneously absorb Messenger contacts, was the first move in the switchover.
"We will work with you over the next few months to help you transition and offer information and help along the way," wrote Tony Bates, president of the Skype Division at Microsoft. "To help you learn how to get the most out of Skype, be on the lookout for some special offers later this year as you join your Messenger friends in the migration."
Windows Live Messenger originally launched in 1999 as MSN Messenger and has consistently been one of the world's most popular messaging platforms.
On its 10th anniversary in 2009, it boasted over 330 million active users every month, but this number has since dwindled.
According to a June 2011 report from OPSWAT, Windows Live Messenger still enjoyed 40.67 per cent of the global instant messenger market share, compared to Skype's 27.39 per cent. However, TechCrunch claims the service may have lost 200 million users since 2010.
Skype, on the other hand, is still on the rise and claims to bring in 40 million users at peak times.
"We're confident that Skype provides a better experience and even stronger network – today and even more so in the future, especially with the addition of the Messenger network," wrote Windows Live's GM, Brian Hall, in the final post on the "Inside Windows Live" blog.