OBJECTIVES: While the economic burden associated with acute hepatitis A outbreaks studied, the impact on health care utilization and associated cost has not been examined over one year in a commercially insured population. METHODS: An observational, retrospective study using HealthCore Integrated Research Database (HIRDSM) medical and pharmacy claims (January 1, 2004 - December 31, 2009) was conducted. Index date was assigned based on the first medical claim for hepatitis A (intake period January 1, 2005 - December 31, 2008). The control group did not have hepatitis.  The index date assigned was of the hepatitis A match.  Subjects had continuous plan eligibility for ≥ 12 months pre- and post-index. Descriptive statistics, including t-tests and chi-square analyses were used. RESULTS: Comparisons (n = 2331 for each cohort) were significant (p <0.01).  Post-index inpatient hospitalization occurred for 482 (20.7%) hepatitis A patients and 193 (8.3%) controls.  Associated mean costs (+SD) were $5,401 (+/-$30,567) and $1,929 (+/-$23,282), respectively. Emergency room (ER) services occurred in 382 (16.4%) hepatitis A subjects versus 277 (11.9%) controls.  Mean costs were $231 (+/-$816) and $139 (+/-$604), respectively. The mean number of outpatient services for the hepatitis A group was 21.5 (+/-22.1) versus 14.7 (+/-18.2) for controls with associated mean costs of $4,985 (+/-$14,936) and $2,948 (+/-$14,624), respectively. The mean number of physician visits were 9.1 (+/-9.9) and 5.5 (+/-7.4) for each group, respectively [mean costs = $1185 (+/-$3712) and $675 (+/-$2183)]. There were 20.13 (+/-24.1) and 19.37 (+/-24.5) pharmacy claims with mean costs of $2255 (+/-$5828) and $1420 (+/-$2656), in the hepatitis A and controls.  Mean total associated costs were $14,056 (+/-$42,666) and $7,111 (+/-$30,519) in the hepatitis A and controls. CONCLUSIONS: In the 12-month post-index period hepatitis A patients had greater total health care utilization and costs compared to controls suggesting hepatitis A is associated with an increase in health care utilization and costs.