Retailers are getting better at challenging under-21s attempting to buy alcohol, according to the latest test purchase results.
Test purchasing company Serve Legal, which works for the likes of Spar and Londis, said supermarkets are now achieving pass rates of more than 70%.
One company is now regularly scoring higher than 80%.
Off-licences are also improving, said Serve Legal, while late-opening convenience stores are also getting their act together.
Overall results show that the off-trade improved pass rates from 56% to 64% during the period from October 2007 to June 2008.
Pass rates had been steady at about 70% for the past six months, but dropped off in the past couple of months.
The on-trade improved from 43% to 67%, overtaking the off-trade for the first time.
The convenience sector, with a 64% pass rate, is still behind the larger supermarkets (71%), but they have closed the gap over the past two months.
