Last week all of the premises targeted in a police operation passed the test after underage teenagers attempted to buy alcohol.
The test purchase operation took place on Thursday 20 July where five premises in Gloucester were visited.
Underage police cadets attempt to buy alcohol to try and gauge whether local businesses are being responsible and abiding by licensing law.
Operations like this happen regularly and the cadets are accompanied by two undercover officers, who observe what happens.
Last Thursday five premises on Southgate Street were visited and underage teenagers attempted to buy alcohol.
The test purchaser never lies about their age and does not produce any ID if asked.
All of the premises passed the test on this recent operation whereas on previous occasions a number of those targeted failed.
On 20 June a test purchase was conducted in Gloucester where five out of eight premises failed and on 11 July four out of six off-licences targeted in Gloucester failed and sold alcohol to a juvenile.
Police Constable Matt Hammond, who was in charge of the operation, said it was good to see some positive results from the latest operation.
He said: "As licensing officer for Gloucester and Forest areas my role is to ensure the licence conditions are complied with as they are in place for a reason.
"Sales to underage teenagers, or drunken people, will not be tolerated and it is good to see some positive results from these recent tests.
"These checks will continue so my message to licence holders, shop owners and staff, is to brush up on your training and challenge those that look under 25-years-old or appear to be drunk."