OBJECTIVES: Our aim was to assess the social insurance costs of hospital treatments for acute stroke in Hungary between 2003 and 2005. We studied how much burden stroke patients impose on the financer (National Health Insurer Fund Administration) in acute and chronic hospital admissions. METHODS: We extracted the data of 'new' stroke patients (ICD-10: I60-64 diagnosis) hospitalized in May 2003 from the database of the financer. We analyzed active and chronic hospital treatment costs of these patients in the period of 12 months before the stroke and in the following first and second 12 months. Data were distributed by sex and age (age groups: 25-44, 45-64, over 65). We studied patients hospitalized in May 2003 with the ICD-10: I60-64 main diagnosis but not treated with the same diagnosis in the previous 24 months. RESULTS: In the first 12 months of the active care the burden of the disease was (male vs. female) 65+: 1018.4 vs. 823.2; 45-64: 1365.6 vs. 1122.0; 25-44: 1480.4 vs. 1224.4 Euro per patient. In the second 12 months the costs were 202.4 vs. 144.8; 96.8 vs. 130.4; 110.4 vs. 99.2 Euro respectively. CONCLUSION: Annual stroke costs of the Insurance Fund - based on our incidence data (3535 patients/month) - amounted to 37.6 million Euros in active and to 4.3 million Euros in chronic hospital care in the first 12 months, which is 1.68% of the total budget. Average costs of stroke are higher in the case of males as are in the case of females, 1459.2 vs. 1212.0 Euro in the first 24 months. The significant difference results from active hospital treatment costs (1326.0 vs. 1048.4 Euro), while the discrepancy is smaller in the chronic hospital care (133.2 vs. 163.6 Euro).