OBJECTIVES: To estimate impact of dutasteride reimbursement on budget from the perspective of National Health Fund (NHF) in Poland. METHODS: Decision-analytic model was developed to assess budget impact of dutasteride. Costs and resource use are from published literature and NHF catalogue of procedures. Costs of drugs, surgical intervention and prostate cancer treatment were taken into account. Clinical data, including complications and prostate cancer rates, were obtained from the clinical effectiveness analyses of dutasteride. Budget impact analysis was performed in four different scenarios with regard to reimbursement reference price and rates (Scenario 1: 50% reimbursement rate, reference price = reference price for Penester; Scenario 2: 50% reimbursement rate, reference price = Avodart price; Scenario 3: 70% reimbursement rate, reference price = reference price for Penester; Scenario 4: 70% reimbursement rate, reference price = Avodart price). RESULTS: In case of Avodart (dutasteride) reimbursement, NHF would save: 65 888-562 612 PLN in year 1, 197 664-1 687 836 PLN in year 2, 300 477-2 625 523 PLN in year 3 and 376 229-3 212 590 PLN in year 4 and later, depending on assumed reimbursement reference price and rate. CONCLUSIONS: Reimbursement of dutasteride would result is savings from the perspective of the National Health Fund in Poland.