In France surveillance underestimates the true burden of acute gastroenteritis (AG). We conducted a population-based, retrospective cross-sectional telephone survey between May 2009 and April 2010 in order to obtain more accurate estimates of the incidence and the burden of AG and to describe healthcare-seeking behaviour for AG. Of the 10 080 persons included in the survey, 260 respondents reported 263 episodes of AG. The incidence rate of AG was estimated at 0·33 cases/person-year (95% CI 0·28-0·37). It was highest in children aged <5 years and declined with age. Thirty-three percent (95% CI 27-40) of the AG cases consulted a physician and 76% (95% CI 70-82) used medication. Our results indicate that there are more than 21 million episodes of AG each year in France. These results allow a more accurate interpretation of the data derived from existing AG surveillance systems.