OBJECTIVES:  The aim of this study was to analyse rheumatoid arthritis (RA) related costs in Finland and stratify them by disease activity and functional capacity. METHODS:  RA patients were identified from the National Register for Biologic Treatment in Finland (ROB-FIN). Data on patient characteristics, disease severity and intravenous medication was recorded in ROB-FIN while other RA related medication costs, outpatient visits, inpatient care, early retirement and sick leaves were retrieved from the Finnish national registers. Average biannual direct and indirect costs were calculated in 2016 euros and adjusted by age and sex. The costs were compared in subgroups stratified by disease activity (measured as disease activity score 28, DAS28) and functional status (measured with health assessment questionnaire, HAQ). RESULTS:  Data on medication and productivity costs were available for 2443 patients while data on outpatient visits and inpatient care were available for 8083 patients. Average biannual direct and indirect costs were 4070€ and 3505€, respectively. The medication accounted for a major part (70%) of the direct costs while inpatient and outpatient care caused 13% and 17% of direct costs, respectively. Mean direct costs and indirect costs were 7432€ and 1932€ for patients using biologics while the corresponding figures for conventional disease-modifying antirheumatic drug users were 5290€ and 2458€, respectively. Mean adjusted total costs including both direct and indirect costs were 8829€ lower (p<0.001) for patients with the best functional status (HAQ≤0.6) as compared to patients with the worst functional status (HAQ>2.1). For patients being in remission (DAS28<2.6) and patient with moderate to high disease activity (DAS28≥3.2) total costs were 5556€ and 12 037€ (p<0.001), respectively. CONCLUSIONS:  The costs of RA are associated with increased disease activity and decreased functional capacity. Medication costs and production losses are the main drivers of RA related costs.