OBJECTIVES: Gastroesophageal reflux disease (GERD) interferes with work productivity through two main mechanisms. Nighttime symptoms disturb sleep and cause daytime tiredness, while daytime symptoms affect work productivity by interrupting physical and social activities. A recent systematic review using data in general working populations from three separate studies indicated that GERD causes a reduction in productivity while at work of around 10%. The level of work productivity is strongly associated with symptom severity, symptom frequency, and the occurrence of nighttime symptoms. Hence, levels considerably higher than 10% have been observed in untreated patients with troublesome symptoms, e.g. up to 40% in patients with GERD-related sleep disturbances. The objective of this study was to estimate the effects of GERD on productivity while at work in France. METHODS: Work productivity data from two international studies in general working populations (n = 1,111 and 1,516, respectively) were used to compare results from the French sub-populations with overall results. Based on the results of these French sub-populations, estimation was made of the total work time lost because of GERD-related reduced work productivity. RESULTS: Findings from the French sub-populations were consistent with overall findings from the total samples, which indicated that GERD causes an average reduction in at-work productivity of around 10%. Assuming a French population of 36 million in working age, a prevalence of diagnosed GERD of approximately 10% and that 63% of GERD patients are employed and work around 36 hours per week, then it can be estimated that GERD causes an at-work productivity loss corresponding to around 380 million work hours per year in France. CONCLUSIONS: Intermediated through reduced productivity while at work, GERD symptoms have implications well beyond the individual patient perspective in terms of number of work hours lost for the French community.