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.
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Philippa has the latest weekend weather for the east
Philippa has the latest weekend weather for the west
Saturday's weather for the east with Philippa