Unofficial overnight figures show 9.1million people tuned in to see Kate win Big Brother.
The final eviction show between 10pm and 11.30pm was the most watched programme on Channel 4 so far this year and the 5th highest rated show since the channel launched in November 1982.
The audience peaked at 9.9 million, over a million more than last years Big Brother Final which averaged 8 million viewers (peaking at 8.8 million).
The combination of Big Brother, Graham Norton, Friends and the Cricket helped Channel 4 become the top rated TV channel for the day with a 22.6% daily share of television viewers.
It's the first time Channel 4 has ever beaten ITV and BBC1 on daily share.