OBJECTIVES: The aim was to focus on the financial burden of co-payments for patients with rheumatoid arthritis under new German law regulations. METHODS: The assessment of all cost data was part of a clinical multicenter randomized RA-trial in Germany. For 136 RA-patients (1987 ACR criteria, mean age 57.4 (±12.5) years, mean disease duration 8.2 (±8.4) years, 77% females) every three months corresponding cost data were derived from 1) a RA-related patient-centered health economic questionnaire, and 2) the payer’s database (insurance and physicians’ association) over a period of 18 months. Co-payments in Germany partly can be derived by analyzing the payers’ data due to specific legal regulations. In addition to that patient-derived data was evaluated. RESULTS: The data was composed in a matrix of different cost domains. Those led to patient co-payments/ year of 417.10€. Visits to a physician accounted for 9.2% (38.40€), non-physician service utilization for 46.6% (194.40€), medication for 23.7% (99€), hospital co-payments for 5.8% (24€), transportation for 13.5% (56.20€), and devices and aids for 1.2% (5.10€) of the overall co-payment costs. CONCLUSIONS: The impact of co-payments on patients with chronic diseases needs to be addressed by policy makers. Even in an environment with relatively low co-payment regulations like Germany the burden for RA-patients can become substantial.