BackgroundThis paper explores the feasibility of delivering a music festival-based drug checking service in Australia, evaluating service design and stakeholder acceptability.MethodsQuestionnaire and interview data were collected from adult service users and key stakeholders. A mixed methods approach was used to analyse the data on implementation, impact and acceptability.ResultsThe trial service tested 170 substances with more than 230 patrons (including individuals who attended in groups). Adult service users had an average age of 21 years. Voluntary participation in the evaluation resulted in 158 participants completing the pre-service questionnaire, most of whom also completed the post-service (147 participants). Eleven in-depth qualitative interviews were conducted with patrons in the weeks following the drug checking. Concordance between what the patron expected the drug to be and drug checking results occurred in 88 per cent (n = 139) of the sample. Evaluation results show that the experience of testing and the accompanying harm reduction brief interventions positively impacted on patrons’ self-reported drug harm reduction knowledge, trust of health providers and stated drug use intentions. The service was received positively by service users.ConclusionThis is the first independent evaluation of a pilot drug checking service in Australia. Consideration of operational feasibility and self-reported behavioural change suggests that the program was successful, although communication about the interpretation of drug checking results could be improved. Future studies should develop strategies for follow-up and consider the applicability of behavioural change theory.