The comic beat a host of talented children.
Only 5.3 million people tuned in for the big event, a far cry from it's peak of over 18 million in 2009
From dangerous fire stunts to bad language - what have been the talking points of this year's BGT?
Many viewers thought someone else deserved the spot.
The grand final will see 11 acts compete to win a cash prize of £250,000 and a chance to perform at the Royal Variety Performance.
After the rules were broken there are now seven Golden Buzzer acts in this year's semi-final.
The UK is hosting the singing extravaganza for a record-breaking ninth time.
The star said it all happened 'last moment'.
The judging line-up has had a rare change after David Walliams' exit.
Tonioli has joined the ITV show this year.
The BGT judge and the Ted Lasso star will join Ukrainian singer Julia Sanina to host the semi-finals.
Dixon said she loves Walliams 'very much'.
The TV star has been a judge on the show for 10 years.
Morgan weighed in after it was reported that Walliams made unpleasant comments about 'BGT' hopefuls.
The one-off special showcases TV stars' singing skills as they talk about the importance of spending time with others.
Which celebrities have lifted the glitterball - and where are they now?
The cheating scandal came out in 2006.
The TV star's skimpy outfits have been criticised in the past.
Cowell, David Walliams, Alesha Dixon and Amanda Holden were joined by hosts Ant McPartlin and Dec Donnelly at The London Palladium.
The new singing contest is set to launch on ITV.
A big-name line-up features in the new Simon Cowell show.
Alesha Dixon was eight months pregnant when she was fronting 'The Greatest Dancer' with Jordan Banjo.
The Britain's Got Talent judge says she wants her daughters to be able to see her perform on stage.
The mother-of-two said she did not have a bad childhood despite witnessing violence.
Phillips was axed from 'Strictly Come Dancing' in 2009, sparking a huge debate about ageism in TV.