Phlebitis and thrombophlebitis arecommon diseases resulting in significant health insurance cost and societal burden in many developed countries.The aim of our study was to calculate the annual health insurance treatment cost of phlebitis and thrombophlebitis in Hungary. The data derive from the financial database of the Hungarian National Health Insurance Fund Administration (NHIFA), the only health care financing agency in Hungary. We analyzed the health insurance treatment cost and the number of patients for the year 2017. The following cost categories were included into the study: out-patient care, laboratory diagnostics, medical imaging, acute in-patient care, chronic in-patient care and drugs. Phlebitis and thrombophlebitis were identified with the following codes of the International Classification of Diseases 10threvision: I80. The number of patients underwent outpatient care was 98,672 (57.0 % women and 43.0 % men) with a mean age of 60.78 years (women: 61.27 years; men: 60.09 years). Number of patients admitted to in-patient hospital care was 15,323 (54.1 % women and 45.9 % men) with a significantly higher mean age of 64.48 years (women: 66.820 years; men: 61.72 years). For the treatment of patients with phlebitis and thrombophlebitis in 2017 the Hungarian National Health Insurance Fund Administration spent 5.114 billion Hungarian Forint (HUF) which equals 16.540 million Euros (EUR). Major cost drivers were acute inpatient care (75.3 % of total health insurance costs), pharmaceuticals (12.8 %) and outpatient care (4.2 %). Phlebitis and thrombophlebitis represent a significant burden with outstanding public health importance for the health insurance system and for the society. Frequency of the disease is higher both in outpatient and inpatient care for women. There is a significant difference (3.6 years) in the onset of the disease between women and men in outpatient.