This bill amends the Social Security Act to broaden the definition of critical access hospitals (CAHs) under the Medicare program, specifically to include certain facilities located on Indian reservations . Beginning August 1, 2025, it permits states to designate a hospital on a reservation as a CAH without requiring it to meet the usual distance criteria from other hospitals. Furthermore, these reservation-based CAHs are allowed to establish distinct part units for psychiatric and rehabilitation services without being subject to the standard bed count limitations. The Secretary of Health and Human Services is also prohibited from considering these specialized units when evaluating whether the facility primarily provides general hospital services. This aims to improve healthcare access and services in tribal communities by providing greater flexibility for these hospitals.