Frontier Critical Access Hospitals (CAHs) are likely among the most vulnerable of CAHs due to the geographic isolation, persistent poverty, and low population density of the frontier counties in which they are located. Currently, the number of CAHs in frontier counties is unknown; consequently, there is no data on their overall financial, operational, clinical, and quality performance, or their technical assistance and support needs. This project aims to provide this valuable information to inform State Flex Programs’ and the Federal Office of Rural Health Policy’s efforts to support frontier CAHs.