The Scottish rockers will play an intimate acoustic set in front of 200 XFM competition winners at King Tut's Wah Wah Hut in Glasgow on Tuesday, April 29. The band will headline T in the Park later this year, making their tenth appearance at the festival.
All money from the gig will go to XFM's fund for War Child.
Biffy Clyro's James Johnston said: "XFM's return to Scotland is massive news, and we're really excited that we've been given the honour of putting on this special gig at King Tut's to give the station the comeback party it deserves. It's going to be a great night, and we can't wait to perform one of our most intimate shows yet."
XFM Scotland's Breakfast Show host Fraser Thomson said: "It's still sinking in that XFM is back in Scotland, not just because we can give the listeners so much fantastic music, but because we can bring them unique musical treats such as this exclusive gig. To have a band the size of Biffy in a venue as iconic as King Tut's is a massive statement. It just screams, 'we're back!'"
To win tickets, tune in from today to Breakfast and Drivetime shows on XFM Scotland, or visit the XFM website.