A peak television audience of 9.3 million watched England thrash Sweden on Tuesday to reach the Euro 2022 final.
There were also two million streams of the 4-0 win across the BBC iPlayer and the BBC Sport website and app.
Both were higher than the figures for the quarter-final against Spain, which had a peak TV audience of 7.6 million, and a further 1.5 million streams.
The Lionesses will face either France or Germany in Sunday’s final.
Their semi-final will be shown live on BBC One and the BBC iPlayer, website and app from 19:30 BST on Wednesday.
The highest peak TV audience for women’s football in the UK is 11.7 million – for England’s World Cup semi-final defeat by the United States in 2019.
There were 28,624 fans at Tuesday’s game at Bramall Lane – a record for a European Women’s Championship semi-final.
The tournament broke the record for most fans at a Women’s Euros by passing the previous mark of 240,055 during the group stage.
Tickets for Sunday’s showpiece at Wembley – which has a 90,000 capacity – have sold out.