OBJECTIVES: To evaluate the out-of-pocket expenditures of Outpatients Department in a tertiary hospital in Thailand and find out the factors those directly influence these expenses.

METHODS: Interviewed 1,201 patients and relatives who come to visit at the Outpatients Department during January to March 2019.

RESULTS: The total out-of-pocket expenditures per patient for a visiting Outpatients Department services was $30.99 per visit (exchange rate 30.28 Baht per 1 US dollar) SD 25.79, median 23.98, range 2.53-252.97. These expenditures can be divided into three categories which are travel expenses, the mean travel expenses were $12.86 (SD 21.66, median 5.28). Food expense was average $4.05 (SD 3.59, median 3.30). The average accommodation was $5.41 (SD 14.14, median 0). This study was calculated the opportunity cost from absence work to see a doctor at the hospital. The mean opportunity cost was $13.95 (SD 5.16, median 15.18). The opportunity cost is the highest proportion which is 39%, followed by travel expense, accommodation fee and food expense, 35%, 15%, and 11%, respectively. The factors that influenced these expenditures were 1) reasons for visiting the doctor 2) department where patients were treated 3) How to reach the hospital 4) number of relatives accompanying the patients and 5) residential area.

CONCLUSIONS: The out-of-pocket expenses for medicine are higher than the minimum wage in Thailand which has a rate of $10.34-11.10 per day in year 2019. This information can be used to reduce the burden by decrease time spend in hospital, develop a health system to referral systems in remote areas including Telemedicine in order to increase access to public health service in remote areas and to reduce the burden of patient’s hospitalization cost which leads to health equity.