OBJECTIVE: To evaluate the feasibility and acceptability of a mobile-based brief intervention (BI), generate preliminary estimates of the impact of the BI and fine-tune the procedures for a definitive randomised controlled trial. DESIGN: Parallel three-arm single-blind individually randomised controlled pilot trial. Eligible and consenting participants were randomised to receive mobile-based BI, face-to-face BI and information leaflet. SETTING: Educational institutions, workplaces and primary care centres. PARTICIPANTS: Adult hazardous drinkers. RESULTS: Seventy-four participants were randomised into the three trial arms; forty-eight (64·9 %) completed outcome evaluation. There were no significant differences between the three arms on change in any of the drinking outcomes. There were however in two-way comparisons. Face-to-face BI and mobile BI were superior to active control for percent days heavy drinking at follow-up, and mobile BI was superior to active control for mean grams ethanol consumed per week at follow-up. CONCLUSION: The encouraging findings about feasibility and preliminary impact warrant a definitive trial of our intervention and if found to be effective, our intervention could be a potentially scalable first-line response to hazardous drinking in low-resource settings.