Home care services funded by Medicare and Medicaid grew rapidly throughout most of the 1990s. During this period some state Medicaid programs transferred costs for home care claims to the Medicare program to reduce their liability and increase beneficiary access to Medicare coverage. This article reports the findings of the first national study of these Medicare maximization billing practices for home care services. Primary data were collected to determine which states conduct retrospective Medicare billing practices and the amounts recovered from Medicare. Our analysis indicates that seven states recovered as much as $265 million from Medicare in state and federal dollars during the 1990s. Ratios of recovered expenditures-to-costs incurred for retrospective billing practices conducted in Connecticut, New York, and Massachusetts are between 5:1 and 7:1. While retrospective billing practices may aid states in reducing Medicaid outlays and potentially help dual Medicare beneficiaries gain coverage for their home care claims, they increase Medicare expenditures for home care at a time of concern for the long-term financial viability of Medicare and illustrate the need for reforming our national long-term care financing policy.