One of the objectives of the 2017 National Prevalence Survey (ENP) was to measure and describe the prevalence of patients treated with antibiotics in healthcare facilities and to compare these findings with data from the 2012 ENP. The survey was conducted on a representative sample of French healthcare facilities using random sampling stratified by region and facility category. Between May 15 and June 30, 2017, 403 healthcare facilities participated, and 80,988 patients were included. The prevalence of patients treated with antibiotics decreased in 2017 (15.12%, 95% CI [14.22–16.06]), whereas it remained stable between 2006 and 2012 (16.60%). In particular, it decreased in several care sectors: obstetrics, post-acute and rehabilitation care (SSR), and long-term care (SLD). It remained highest in intensive care units, where one in two patients was treated with antibiotics. The prevalence of patients treated with antibiotics decreased among children under 15 and patients over 65, as well as among less vulnerable patients (non-immunocompromised patients and those with non-fatal illnesses), which could suggest more controlled antibiotic use in these patient groups. The prescribed antibiotic dose exceeds the defined daily dose (DDD) for amoxicillin and the amoxicillin-clavulanic acid combination, as reported in the literature. The duration of surgical antibiotic prophylaxis, often extended beyond 24 hours, raises questions in light of current recommendations. It has not decreased since 2012 except in orthopedic and trauma surgery departments. One in five treatments was changed for the same reason for prescribing. This change more frequently leads to an escalation rather than a de-escalation of therapy. The decline in the prevalence of patients treated with antibiotics encourages continued efforts to promote the appropriate use of antibiotics.