Rheumatoid arthritis is an inflammatory disease that affect 0.5% - 1.0% of the population world-wide and approximately 0.5% in Norway. RA places a considerable burden on patients in terms morbidity and mortality, and on society in terms of costs. The aim of this master thesis was to explore the costs of hospital care and pharmaceuticals in patients with rheumatoid arthritis and study the differences in these costs across time and region. Data on all episodes of hospital care during 2009 – 2012 were collected from the Norwegian Patient Registry using «M05 – Seropositive rheumatoid Arthritis» and «M06 – Other Rheumatoid Arthritis» as either main or secondary diagnoses as inclusion criteria. The data included information about age-group, sex, region, diagnosis and use of biologic pharmaceuticals. Data on pharmaceuticals dispensed from pharmacies during 2009 – 2012 were extracted from the Norwegian Prescription Database. The estimated total costs of hospital care and pharmaceuticals for rheumatoid arthritis in Norway were NOK1 billion in 2012. Hospital care and biologic DMARDs administered in hospital accounted for 58%, private specialist care 0.6%, rehabilitation in private clinics 1.0% and prescription drugs 40% of the costs. The registered hospital care costs increased during 2009-2011 and decreased by 5% from 2011 to 2012. Per capita hospital care costs varied considerably with a difference of more than 20% between the regional health authority with the lowest and the highest costs. The costs of private specialist care were considerably higher in the South-Eastern- and the Western Norway regional health authority compared to the Northern- and the Central Norway regional health authority in terms of total costs and costs per capita. The costs of care in private rehabilitation clinics decreased during the period and differed across regions. The Northern Norway regional health authority had the highest- and the Western Norway regional health authority had the lowest costs of care in private rehabilitation clinics. The costs of patient-administered disease modifying antirheumatic drugs (DMARDs) (Biologic and non-biologic) increased from NOK351 million to NOK414 million during the period. Despite the increasing use of DMARDs there was no reduction in rheumatic surgery.