Test purchase operations on 21 licensed premises in Wellingborough and east Northamptonshire resulted in four fixed penalty notices being issued.
The figures show a refusal rate of more than 80 per cent, with eight out of 10 premises tested refusing to serve alcohol to underage drinkers.
In the Wellingborough area, 11 premises were tested and two licence breaches were penalised, at shops in Wellingborough and Finedon.
In the east of the county, 10 premises were tested – seven in Rushden, two in Raunds and one in Irthlingborough.
Again there were two breaches, at a food and wine store in Rushden and also a cheap drink shop in Rushden.
Sgt Sharan Wildman, who led last weekend’s operation in the Wellingborough area, said: “I am pleased that the operation was a success and that the majority of licensees are behaving responsibly when it comes to serving alcohol.
“Those who do not abide by the law will be fined and dealt with appropriately.
“Selling alcohol to underage young people not only damages their health but contributes to instances of anti-social behaviour which blight the lives of so many within our communities.”
Sergeant Phil Holton, of East Northants South Safer Community Team, led the Rushden-based operation aiming to tackle anti-social behaviour, crime and other harm caused by young people and the consumption of alcohol.
Officers from the SCT, supported by Specials and two teenagers, undertook test purchases at the licensed premises.
He said: “The outcome is pretty encouraging.
“The Licensing Unit will write to all of those premises to make them aware that they ‘passed’ the test.”
Test purchase operations are integral to the force’s drive around alcohol responsibility, led by Chief Constable Adrian Lee who is the national police lead on alcohol harm.
He said that police and partners all had a major role in working towards reducing alcohol harm in Northamptonshire.
He said: “Everyone has a responsibility around alcohol be they legislators, enforcement agencies, retailers, traders, teachers, parents and not least the drinkers themselves.
“How are we all thinking about drinking?
“We are looking at the whole range of powers available to police and partners around alcohol-related crime and disorder to ensure that they are used extensively and effectively.
“Where licensees are in clear breach of their licence we will remind them of their responsibilities and if they are repeatedly in breach we will look to come down very hard on them.
“Irresponsible alcohol sales can create huge problems within our communities and it is those who are drunk by the time they go into our town centres for a night out that invariably cause us the problems with violence, disorder and anti-social behaviour.”
Anyone who is concerned about the sales practices of any licensed premises is encouraged to report their concerns to their local Wellingborough or East Northants South Safer Community Teams.