AbstractIntroduction and AimsBhutan has a high incidence of alcohol‐related disease. With economic development, motorised transport is proliferating, increasing the potential for traffic injury. We investigated drink‐driving in the country's largest urban environment.MethodsWorking with police, we set up checkpoints at major thoroughfares in Thimphu, on Tuesday, Friday and Saturday nights, from May to July 2017. Police directed cars to testing bays where drivers were breathalysed and interviewed.ResultsAll 1596 drivers stopped by police were breathalysed, and 212 (13%) tested positive. Blood alcohol of >0.02 g/dL (which we defined as ‘probable impairment’) was detected in 178 drivers (11%), while 67 (4.2%) exceeded the legal limit of 0.08 g/dL. Probable impairment was more common in men, older drivers, on Tuesdays (versus Fridays or Saturdays) and later at night.ConclusionDrink‐driving is very common at night‐time in Bhutan. Routine roadside random breath‐testing, and media campaigns emphasising the risk of apprehension and consequent serious financial and social penalties, should be considered to deter drink‐driving.