There is a substantial gap between people having a mental disorder and those treated for this disorder. Studies that assessed the influence of age on healthcare use for major depressive disorder (MDD) have provided inconsistent results. We aimed to assess healthcare use in terms of treatment-seeking and psychotropic medication use in four age groups of 45- to 85-year-old community dwellers meeting criteria for MDD.Data stemmed from CoLaus|PsyCoLaus, a population-based prospective cohort study. Diagnostic information on mental disorders, utilization of professional healthcare and psychotropic drugs was elicited using a semi-structured interview. Associations between age groups and healthcare use were established using logistic regression models with serial adjustments for socio-demographic and depression characteristics as well as comorbid mental disorders and cardio-metabolic features.Compared to participants of the youngest age group (ages 45 to 54 years), (1) those older than 75 years were less likely to use healthcare from psychiatrists or psychologists (OR: 0.4 [95% CI 0.17-0.96]), although the frequency of using any professional health care did not vary across age groups; (2) those older than 55 years used any psychotropic medication more frequently; and (3) those aged 55-64 years used antidepressants more frequently (OR: 1.61 [95% CI 1.07-2.44]), whereas those aged 65-74 years used anxiolytics more frequently (OR: 2.30 [95% CI 1.15-4.58]).Age is a complex biological and social factor that influences healthcare use.