Results from Camelot's test purchase scheme, Operation Child showed that in the first nine months of 2006, refusal rates were the highest they had been since the initiative was launched in 1999. In 8,390 visits, 94.4% of test purchasers were refused, up from 92.7% for the 10,386 visits carried out in 2005.
Independent retailers performed slightly better than supermarkets, with respective refusal rates of 95.7% and 94.6%.
Retailers in the north east were most vigilant, with 96% refusing to sell.
With a 92.2% refusal rate, Greater London retailers made a significant improvement on their 2005 score of 85%. However, store owners in the south west of England performed worst, with an 88.8% refusal rate.
Operation Child employs young people aged over 16 but who look younger to buy tickets along with an investigator as part of a mystery shopping exercise.
If a retailer sells tickets without asking for ID three times, his terminal is removed. "We will continue to work in partnership with retailers in order to reduce the levels of underage sales and save them from the risk of prosecution," said Steve Lucas, director of sales for Camelot.