Abstract Purpose Proton pump inhibitor (PPI) drugs are approved for the management of gastric acid–related diseases, mainly treatment of gastroesophageal reflux disease, treatment of nonsteroidal anti-inflammatory drugs (NSAID)–related gastrointestinal complications and prevention in at-risk patients, Helicobacter pylori eradication, and treatment of ulcers. PPIs are one of the most commonly prescribed drug class worldwide, and off-label use is widespread. The aim of this study was to describe outpatient PPI use of the whole adult population in France, based on the French National Health Data System (SNDS). Methods All individuals aged 18 years or older, with at least one dispensing for PPI between January 1, 2015 and December 31, 2015, were identified as PPI users. PPI users were considered as new users if they received no dispensing for PPI in the prior year. New users were followed until treatment discontinuation or up to 1 year, whichever occurred first. Characteristics of new users and of their PPI treatment were described, overall and separately by treatment indication. Results In total, 15,388,419 PPI users were identified in 2015 (57.0% women; mean age 57.0 years), accounting for 29.8% of the French adult population. Of them, 7,399,303 were new PPI users; mean treatment duration was 40.9 days, and 4.1% received a continuous PPI therapy lasting more than 6 months (10.2% among new users > 65 years versus 2.4% among those 18–65 years). For 53.5% of new users, indication for PPI therapy was a co-prescription with NSAID; in this indication, the large majority of patients (79.7%) had no measurable risk factor supporting a systematic prophylactic co-prescription of PPI. A proportion of 32.4% of new users did not have any identified comedication or inpatient diagnosis supporting an indication for PPI therapy; among them, only a small proportion (7.3% overall, and 8.4% of patients aged > 65 years) underwent a procedure investigating the digestive tract at the time of PPI initiation. Conclusion The results of this study suggest PPI overuse in France, not always in line with the French guidelines. In particular, inappropriate co-prescription with NSAID was frequent. Efforts should be made to limit PPI treatment to appropriate indications and durations.