New C&I facilities at the Twickenham Stadium are set to boost its turnover by around £2m.
The stadium's South Stand opened in September and venue owner Twickenham Experience anticipates turnover to rise from under £1m to £3m in the first year of business.
Twickenham Experience managing director Chris Morris said: "We will see revenues increase next year and the year after that."
Turnover for 2010-2011 would be around £3.5m, he said.
The facilities added an additional 5,000sqm of conference and exhibition space, including the Live Room, with tiered seating for up to 400 delegates and the Rose Suite, with seating capacity for 800.
The London Marriott Hotel Twickenham will open next month with 156 rooms, a restaurant and bar.