OBJECTIVES: Previous studies have shown that the majority of Medicare patients with HCV are under age 65.  This study examines how patient characteristics and cost differ between Medicare patient age groups. METHODS: An analysis of HCV patients was conducted using the 2010-2011 Centers for Medicare and Medicaid Services Parts A and B fee-for-service claims.  Patients with an HCV ICD-9 code and 6 months of follow-up were included.   Patient characteristics, resource utilization and 6-month costs were compared between patients age<65 and age≥65.  The impact of age on medical costs adjusting for demographics, reason for entitlement(OREC), Medicaid status, and overall health status (measured by CCI) was assessed using generalized linear models fit with a gamma distribution and log link function.  RESULTS: