ITV said the programme was the highest rating show of the year so far, nudging ahead of a Coronation Street which pulled in 11.2 million in January.
Adding viewers for ITV's +1 channel brought the audience to 11.9 million for the BGT finale, with a peak audience of 14.5 million.
More top news
Thames Valley Police have spoken out after two men were found guilty of Kerry Reeves' murder
Friday night's forecast for the west of the region
It's a Bank Holiday weekend, with half term for many. Here's how it's looking on the roads, in the skies, and at getaway hotspots