OBJECTIVES: To examine hemophilia-related healthcare costs among persons with hemophilia A at six US Hemophilia Treatment Centers (HTCs). METHODS: Data on 315 persons aged 2-65 years from seven states enrolled in Hemophilia Utilization Group Study (HUGS-Va, 2005-2007) were obtained prospectively from interviews and chart reviews. One-year healthcare utilization data (HTC visits, laboratory tests, outpatient visits, emergency room (ER) visits, hospitalizations) and units of clotting factor dispensed were used to impute costs. HTC visit and laboratory test expenditures were obtained from Medicare payment schedules. Inpatient costs were estimated using ICD-9 codes and HCUP National Inpatient Sample charges adjusted for cost-to-charge ratio from MedPAR. ER costs were estimated using MEPS data. Factor costs were estimated using Medicare Part B reimbursement rates. Per-unit prices for non-factor medications were estimated using wholesale acquisition costs. All costs were converted to 2010 US dollars. Socio-demographic and clinical characteristics associated with higher costs were analyzed using a multivariate model. RESULTS: Fifty-one percent of participants were adults; mean age was 21.2(±14.8) years. Two-thirds had severe hemophilia. 94% used clotting factor; 64% of severe patients infused prophylactically. Annual mean healthcare costs per patient (excluding medication) were $3,912(±9,267), $3,975(±8,422), $16,185(±46,097) and $2,852(±7,721), respectively, for patients with mild, moderate, severe hemophilia on episodic treatment, or severe hemophilia on prophylactic treatment. Annual hemophilia-related medication costs for the same groups were $42,377(±115,246, median:$3,573), $63,063(±113,571, median:$22,587), $159,830(±143,220, median:$113,263) and $275,376(±178,573, median:$246,333), respectively (P<0.0001). Inhibitor patients (N=16) had healthcare and medication costs of $13,086(±19,163, median:$2,223) and $721,603(±914,069, median:$199,319), respectively. Older age, higher weight, greater hemophilic severity, with insurance coverage, prophylaxis treatment, and positive inhibitor were associated with higher total costs. CONCLUSIONS: Hemophilia is a costly disorder. This data provides information on annual healthcare and factor costs associated with hemophilia. Identifying factors associated with increased healthcare utilization and outcomes will advance our understanding of the economic impact of this condition.