The bookie lost out to punters at the Grand National and Royal Ascot, but a record World Cup helped the group report a 1 per cent rise in half-year underlying earnings to 135.6m.
William Hill said it made 32.2m in gross winnings from the football tournament – 19.3m of which came through in the first half of its year.
Spain's victory generated a profitable return for bookmakers after the European champions' open-ing defeat to Switzerland deterred many punters.
Bookies also benefited from patriotic bets on a poor England team, as well as Brazil's loss to Holland in the quarter-finals and 2006 finalists France and Italy's exit at the group stage.
In the seven weeks since the half year, net revenues across William Hill rose 26 per cent, up 20 per cent at its 2,350 betting shops thanks to the tail-end of the World Cup and ongoing strength in gaming machine turnover.
Analysts expect the group to deliver full-year underlying earnings of around 258m.
Meanwhile, football pools firm Sportech said betting games launched during the World Cup attracted 12,000 new online players as it stepped up the turnaround of the rebranded Littlewoods and Vernons business.
The Liverpool-based firm said fixture betting games Super Six and Score 3 had been extended into the current football season in a bid to pull in a new type of punter and boost prospects for its New Football Pools operation.
The World Cup boost came at the end of a six-month period which saw Sportech report pre-tax profits of 5.8m, down from 6.9m a year earlier.