In 2016, U.S. Geological Survey St. Petersburg Coastal and Marine Science Center (USGS SPCMSC) researchers and academic collaborators collected cores of mangrove peat from two islands in the Florida Keys: Snipe Key (24.679°N, 81.653°W) and Swan Key (25.349°N, 80.251°W). This data release contains the radiocarbon ages and associated data for peat samples analyzed throughout the two cores (SNK-16-C1 and SBC-16-C10).