OBJECTIVES: To compare treatment costs of all anti-TNFa biologics treatments in rheumatoid arthritis (RA), akylkosing spondilitis (AS) and psoriatic arthristis (PsA) in the Brazilian public health care system. METHODS: In Brazil, four anti-TNFa biologics are available for the treatment of RA, AS and PsA: adalimumab, etanercept, infliximab, and golimumab. Yearly treatment costs were calculated for an average patient of 70 kgs, considering dose and dosing intervals as defined in the label for each drug. The price for adalimumab, etanercept and infliximab was gathered from the official government website for centralized purchasing, as these drugs are already reimbursed for the three indications. The price of golimumab was defined according to law, based on the mandatory government discount of 24,38% over the official list price. RESULTS: Golimumab has the lowest treatment cost across the biologics in all indications, at R$ 21,471.94 per patient per year. This treatment cost does not vary across indications or across years of treatment, as it does not include a higher initial dose. Infliximab has the second lowest treatment followed by adalimumabe at a cost of R$ 29,280.00 and R$ 36,374.00 per patient respectively. Due to higher dosing of infliximab for AS and PsA, the average cost per patient is R$ 37,820.00 similar to the yearly cost of adalimumab. Etanercept has the highest treatment cost across all indications at R$ 44,800 per patient per year, with the highest number of vials per patient per year. CONCLUSIONS: With the lowest treatment cost, golimumab is an important treatment option for RA, AS and PsA. Given the high expenditure of the Brazilian government with anti-TNFs, golimumabe can decrease government expenditure between 27%-50%. Considering the total health care expenditure of R$ 1.67 million with adalimumab, etanercept and infliximab in the last 12 months, golimumab has the cost saving potential of about R$ 449 million.