The rugby coverage has been pulling in quality audiences, dominated by ABC1 males, for the broadcaster.
Last Saturday's semi-final, in which England beat the French 24-7, drew an average audience of 7.6m and peaked at 8.8m, a 64% share of viewing.
An ITV Sport spokesman said that although rugby audiences are typically lower than other sports, these were particularly good figures for rugby. The England-Argentina quarter-final match in the Football World Cup in 1998 drew 23.8m.
There are no comparable figures with the last Rugby World Cup four years ago, because England got knocked out in the quarter-final by New Zealand. Their last match in that tournament drew 6.6m, but that was broadcast on a Saturday afternoon.
With more than 10m expected for the final, ITV could profit as advertisers look to reach the largely affluent male audience the game will attract.
"The type of audience is a good profile for advertisers," an ITV spokesman said. "It builds as the England team succeeds."
He added that the true figures will be more than those quoted because many people will watch from clubs and bars.
The England-Wales match on Sunday November 9 at 10am drew an average audience of 6m and peaked at 7.1m.
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