In France, published prevalence estimates for pervasive developmental disorders (PDD) and/or autism spectrum disorders (ASD) are rare and limited to data collected by the two French registries of childhood disabilities, covering specific geographic areas and children aged 8 years. The objective of this study is to estimate the prevalence of these disorders based on healthcare utilization, at the national and regional levels, for the entire population. Patients can be identified in the National Health Data System (SNDS) using code F84 from the International Classification of Diseases, 10th Revision (ICD-10). A separate analysis of the RIM-P (hospitalizations in public and private psychiatric facilities and outpatient care in public psychiatric facilities) allows for a description of the distribution of the various diagnoses under code F84. The rates were standardized to the age structure of the French population in 2015. In 2017, 119,260 people with ASD were identified through healthcare utilization, corresponding to a crude prevalence of 17.9 per 10,000 (27.9 among men and 8.5 among women), with the highest rate observed among 5- to 9-year-olds (72.2). Prevalence was highest in Brittany for both genders. A steady increase in prevalence was observed over the study period of 2010–2017 (from 9.3 to 18.1). The distribution (non-exclusive) of diagnoses was: “other PDDs or unspecified PDDs” (53% of patients), “childhood autism” (28%), “atypical autism” (11%), “Asperger’s syndrome” (8%). The prevalence rates observed among children aged 7 and older are close to those reported by the two French registries, suggesting that most children receive care through the healthcare system. Despite its limitations, this nationwide analysis covering all age groups is the first of its kind in France. In the coming years, the SNDS will gradually integrate medical and social care data from the Departmental Centers for People with Disabilities (MDPH), which should allow for more accurate prevalence estimates.