William Hill branches in Yorkshire are leading the way in tackling underage gambling.
The bookmaker, which employs more than 1,200 people in the region, was ranked among the best performing retail betting outlets in undercover tests.
Staff in Yorkshire challenged testers aged 18 and 19 in 87.1 per cent of visits. This compares to 86 per cent across William Hill nationally. The bookmaking sector averaged 82 per cent across the country.