The band awarded DJ John Kennedy the winner of the Xfm Inspiration Prize for 20 years of service at the event, which took place at London's O2 Academy in Brixton.
Kennedy, who was expecting to give the prize to Mumford & Sons before they announced him as the winner instead, said: "Mumford & Sons are an amazing band and I was going to say in my speech, that I prepared for hours, how they are so great.
"They stuck to themselves, they followed their own vision and they made it work. There are too many highlights to mention from my years at Xfm but this is definitely up there. I feel honoured to receive this award."
Ted Dwayne from Mumford & Sons said: "John's had a place in our hearts before we were even a band.
"We all grew up in London listening to Xfm, listening to Xposure as any self-respecting teenager does in London, and John showed us loads of great music and continues to do so for loads of people every night of the week and we're just really grateful that John does what he does and stays true it."
Meanwhile, Editors and The Courteeners headlined the show, where the Birmingham-based band performed their biggest hits including 'Munich' and 'Blood' as well as exclusively unveiling new songs 'Formaldehyde' and 'Nothing'.
Other acts to play the show, which is now in its ninth year, included Theme Park and singer-songwriter Lucy Rose.
Click through our gallery below of this year's Xfm Winter Wonderland in London:
Copyright: PA Images Dominic Lipinski/PA Wire