The five-piece male theatre vocal group were the surprise winners of this year's series, beating favourites Bars and Melody, after a rousing performance of 'Stars'.
The young rap and vocal duo finished in third place behind opera singer Lucy Kay.
Speaking after Collabro's winning performance, judge David Walliams said: "Fantastic guys. You are stars. Your voices are just perfect together, they sound incredible."
Simon Cowell said: "You decided the kind of band you wanted to be and the music you wanted to make, which is really important. The harmonies were spot on, preparation great. Britain really has got talent."
Alesha Dixon said: "Such a confident strong, powerful performance. You have made your mark. Perfection - I love you guys."
And Amanda Holden said: "Every single one of you has the most beautiful tone. I think we could be looking at the winners of Britain's Got Talent."
Lucy - who sang the opera classic 'Nessun Dorma' in the final show - apologised to the person who had placed a £1000 bet on her to take the title and added that she thought Collabro were always going to win.
Vocal harmony group Jack Pack finished fourth, illusionist Darcy Oake came fifth and 15-year-old singer James Smith was sixth.
Cheryl Cole also featured in the final, debuting her new single 'Crazy Stupid Love' and was joined on stage by Tinie Tempah, who raps on the track.
'X Factor' winners Little Mix also performed their new single 'Salute' and were joined on stage by previous 'Britain's Got Talent' champs, Diversity.
Collabro - made up of members Jamie, Matthew, Tom, Michael and Richard - walk away with a £250K prize and will perform in front of the Queen at this year's Royal Variety Performance.