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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The grass pollen risk will be very high during warm, sunny weather. Weed pollen will also be airborne
Dry and sunny with long spells of sunshine in the south east and feeling hot
Fine and dry with some good long sunny spells, especially this afternoon and early evening and feeling very warm