Our objective was to investigate the potential cost savings of immunization information systems (IIS) in performing some administrative tasks associated with the federal Vaccines for Children (VFC) program at the state and practice levels. VFC is an entitlement program providing free vaccine to eligible children. We timed the staff of the Utah Department of Health (UDOH) and 72 private VFC practices for administrative VFC-related tasks from September 2003 through March 2004. Time measurements included time for practices to produce VFC reports and for UDOH staff to assess practice coverage levels and process VFC reports manually or via the Utah Statewide Immunization Information System (USIIS). Median cost savings to the state health department could be as much as $11 740 annually. Utah VFC practices could save up to a maximum of $446 annually per practice by using USIIS for VFC tasks. If applied to the 218 enrolled private practices statewide, this would result in a median total cost savings of $17,615 ($15,519 for reports and $2,096 for pulling medical charts).