The U.S. Fish and Wildlife Service announces the availability of final revised maps for 89 units of the John H. Chafee Coastal Barrier Resources System (CBRS) in Florida, Georgia, Louisiana, Maine, and the Great Lakes region of New York. The maps, dated December 29, 2023, became effective December 19, 2024. Boundary modifications to 13 units reflect natural forces such as erosion and accretion; two Florida units were also corrected for administrative errors. This is a map-revision notice under the Coastal Barrier Resources Act, not a NEPA environmental review, and no environmental impact analysis is presented.1