Although waterpipe smoking is growing in popularity worldwide, its epidemiology remains poorly understood. The purpose of this study was to determine the prevalence and attitudes of waterpipe smoking among 489 medical students (54.6% female; mean age 20.4 ± 2.0 years) in the United Kingdom by conducting a cross-sectional survey. Waterpipe smoking was more common than cigarette smoking (current 11.0% vs. 6.3%, ever 51.7% vs. 16.8%). Mean age at waterpipe smoking initiation was 16.1 ± 2.6 years. Sex, ethnicity and sociodemographic factors did not predict current/ever waterpipe smoking. Tobacco control efforts need to consider waterpipe smoking in the light of this high prevalence.