Objective: To quantify the frequency of psychiatric disorders in the outpatient setting in Peru, from 2018 to 2021. Methods: Observational cross-sectional study using outpatient morbidity data from Perú’s National Superintendence of Health. Psychiatric diagnoses were identified using ICD-10 codes. The frequency of major psychiatric disorder groups is described by demographic variables. Monthly trends, as well as the number of outpatient visits per 10,000 population at the subnational level, are also presented. Results: Between 2018-2021, psychiatric disorders accounted for 3,142,685 outpatient visits (2.3% of all) in Peru. Across working age groups, anxiety and depressive disorders comprised approximately 6 out of 10 psychiatric outpatient visits in women, and 4 out of 10 in men. Monthly trends showed two peaks in the absolute number of psychiatric outpatient visits during the pre-pandemic period: April-Mayand September. Provinces in the Highlands had the lowest outpatient visits per 10,000 population. Conclusions: Psychiatric disorders represent a small fraction of the outpatient visits in Peru, with anxiety and depressive disordersas the most frequent. National strategies targeting outpatients with psychiatric disorders should consider demographic differences, monthly trends, and the impact of the COVID-19 pandemic.