OBJECTIVES: Clinical guidelines are available at a national level for the treatment of rheumatoid arthritis (RA) in the Brazilian public health system (SUS). This research aims to compare the annual treatment cost of biological therapies according to the sequence of treatment recommended by these guidelines. METHODS: Clinical guidelines recommend the initiation of biological treatment with TNF inhibitors: adalimumab (ADA), certolizumab pegol (CTZ), etanercept (ETN), golimumab (GOL) or infliximab (IFX). Upon secondary failure to a TNF inhibitor, the switch to a second TNF inhibitor, preferably GOL is recommended, or to abatacept (ABT), tocilizumab (TCZ) or rituximab (RTX). Cost-minimization analyses were performed for the two recommended treatment lines. Annual treatment costs were calculated for a patient of 70 kg, following doses/intervals defined in the guidelines. Only drug acquisition costs were considered in the analyses. Prices were gathered from the official government website. Since IFX, ABT and TCZ doses are weight-dependent, deterministic sensitivity analysis (DSA) was carried out to determine the impact of this parameter on results. RESULTS: GOL currently presents the second lowest annual treatment cost among TNF inhibitors at R$15,983/patient/year, 14% and 7% lower than ADA and ETN, respectively, which are accountable for 68% of RA patients in SUS. As for the second line of treatment, GOL annual cost (R$15,983) is very similar to ABT (R$16,502), TCZ (R$15,161) and RTX (R$15,268). The DSA shows that annual treatment cost with IFX, ABT and TCZ can reach up to R$22,089, R$22,002 and R$23,825, respectively, assuming a patient of 110 kg. CONCLUSIONS: GOL represents an important treatment option for RA patients in SUS, presenting the second lowest annual treatment cost among TNF inhibitors, with greater convenience (once a month). In second line, GOL presents annual treatment cost similar to the alternatives however more predictable since ABT and TCZ dosages are weight-dependent.