Issue AddressedSelling alcohol to a minor is a serious offence in the New South Wales Liquor Act. However, minors report they can purchase alcohol easily. This study used an intersectoral partnership between the Central Coast Local Health District (CCLHD) Health Promotion Service, and Liquor & Gaming NSW (L&GNSW) Compliance Operations to test a site visit intervention to increase ID checks at packaged liquor outlets (PLOs).MethodsAs the current legislative framework does not allow minors to attempt to purchase alcohol from PLOs, even under compliance operations, this study employed pseudo‐minors aged 18–19 years. Pseudo‐minors visited all PLOs on the Central Coast, NSW in four survey rounds, attempting to purchase alcohol without ID. If a PLO sold alcohol to the pseudo‐minor, they received a visit from a Health Promotion Officer and L&GNSW Inspector to inform them of the sale and that they are at risk of selling alcohol to a minor.ResultsSite visits were an effective intervention to increase the rates of ID checking. Alcohol sales to pseudo‐minors without ID decreased from 34% in Round 1 to 7% in Round 4. Young sales staff and independent stores were less likely to check ID.ConclusionsThis intervention was associated with some of the lowest rates of underage alcohol purchasing reported to date. However, it may not be sustainable in the long term. It is recommended that: future studies randomise site visits to investigate their contribution to the observed reduction, cost effectiveness of the intervention is explored and legislative change to allow controlled purchase operations for alcohol is considered.So What?Young people under 18 years of age should not be able to purchase alcohol from liquor licence outlets, and strong laws apply if a sale is detected. However, despite these rules, young people still report they can access alcohol in this manner. Whilst our intervention of site visits with the regulatory body saw decreases in sales to our pseudo‐minors, we advocate for controlled purchase operations (similar to tobacco control) as a more sustainable and effective intervention to reduce sales to minors ‐ while this is not yet legislated for packaged liquor outlets in Australia, it is deemed best practice in other countries.