Objectives We aimed to assess the impact of the COVID-19 crisis on the occurrence of new hospital admissions for cases of psychosis in France. Method We conducted a retrospective observational study from the French national PMSI database. We included patients hospitalized between 2018 and 2020 with a principal diagnosis of schizophrenia or delusional disorder with no history of psychosis in the previous 10 years. In total, we included 77,172 inpatients at crisis centers and/or in full-time hospitalization at 465 French hospitals. We assessed the number of inpatients during the year of the Covid crisis (2020) and the two years prior (2018, 2019). Results The number of inpatients in full-time hospitalization decreased gradually from 2018 to 2020 by 10.6%. This downward trend was observed in all age groups. In contrast, in crisis centers the number of inpatients increased by 13.4% between 2019 and 2020, while a 7.6% decrease was seen between 2018 and 2019. The greatest increase was observed in the 31–60-year age category, and particularly amongst 46–60-year-olds, i.e. 38.0%. Conclusion The COVID-19 crisis was associated with an increase in the number of inpatients with a new episode of psychosis in crisis centers but not in full-time hospitalization. The profile of patients in crisis centers was different from that seen in preceding years and included more middle-to-late age adults. Particular attention should be given to this category of patients in the crisis environment to prevent the occurrence of new cases of psychosis in France.