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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Thursday's weather for the west of the region
Thursday's weather for the east of the region
Three young women with Down's Syndrome have made an impassioned appeal to councillors to reverse plans to shut their respite centre.