This 2020 edition of the MACStats: Medicaid and CHIP Data Book presents the most current data available on Medicaid and the State Children’s Health Insurance Program (CHIP), two programs that provide a safety net for low-income populations who otherwise would not have access to health care coverage and that cover services other payers often do not cover. The MAC Stats data book compiles the broad range of Medicaid and CHIP statistics that MACPAC regularly updates on macpac.gov into a single, end-of-year publication. Our purpose is to bring together in one place federal and state data on Medicaid and CHIP that come from multiple data sources and are often difficult to find.