Background: Out-of-pocket payment encompasses the costs that patients pay for healthcare services, which is an inefficient approach to healthcare financing as it may lead to poverty. Objectives: The present study aimed to determine the risk of catastrophic health expenditures due to non-medical costs in the outpatients in Qazvin, Iran. Methods: This cross-sectional survey was conducted on 341 outpatients referring to the internists of Velayat Hospital and Bu-Ali Sina Hospital in Qazvin. The required data were collected using a researcher-made questionnaire and the prescriptions of the patients. Out-of-pocket payments were defined as the direct medical and non-medical costs within one month. Results: The mean out-of-pocket payments of the patients in one month was 49.97 dollars, 75.8% of which covered direct medical cost (disease diagnosis and treatment), and 24.2% covered direct non-medical costs to receive health services. The highest out-of-pocket payments were for diagnostic/laboratory tests (50.3%), medications (21.5%), and transportation (18.2%). In addition, the exposure rate to catastrophic expenditures was estimated at 31%, and the patients with lower income had less exposure compared to those without incomes. Conclusions: According to the results, direct non-medical costs were associated with the increased out-of-pocket payments of the patients, which in turn led to the higher rates of catastrophic expenditures.