The Bay of Islands has come up trumps again in the latest controlled purchase operation, where 16-year-old volunteers attempted to buy alcohol at 16 licensed outlets.
No sales took place.
It was a different story in the Kaipara though, with four of 18 outlets selling alcohol to the teenagers.
Alcohol harm reduction officer Sergeant Howard Clement said the Kaipara result was disappointing.
"The premises involved should have better systems in place regarding not selling alcohol to minors. These sales of alcohol should not be occurring," he said.