This U.S. Geological Survey (USGS) data release provides a digital geospatial database for the geologic map of the Bayhorse area, central Custer County, Idaho (Hobbs and others, 1991). Attribute tables and geospatial features (points, lines, and polygons) conform to the Geologic Map Schema (GeMS, 2020) and represent the geologic map as published in the USGS Miscellaneous Investigations Series Map I-1882 (Hobbs and others, 1991). The 357,167-acre map area represents the geology at a publication scale of 1:62,000. References: Hobbs, S.W., Hays, W.H., and McIntyre, D.H., 1991, Geologic map of the Bayhorse area, central Custer County, Idaho: U.S. Geological Survey, Miscellaneous Investigations Series Map I-1882, scale 1:62,500, https://doi.org/10.3133/i1882. U.S. Geological Survey National Cooperative Geologic Mapping Program, 2020, GeMS (Geologic Map Schema) - A standard format for the digital publication of geologic maps: U.S. Geological Survey Techniques and Methods, book 11, chap. B10, 74 p., https://doi.org//10.3133/tm11B10.