The data release for the geologic terranes of the Hailey 1 x 2 degrees quadrangle and the western part of the Idaho Falls 1 x 2 degrees quadrangle, south-central Idaho is a Geologic Map Schema (GeMS)-compliant version that updates the GIS files for the geologic map published in U.S. Geological Survey (USGS) Bulletin 2064-A (Worl and Johnson, 1995). The updated digital data present the attribute tables and geospatial features (lines and polygons) in the format that meets GeMS requirements. This data release presents the geologic map as shown on the plate and captured in geospatial data for the published map. Minor errors, such as mistakes in line decoration or differences between the digital data and the map image, are corrected in this version. The database represents the geology for the 6.1 million-acre, geologically complex Hailey quadrangle and the western part of the Idaho Falls quadrangle, at a publication scale of 1:250,000. The map covers primarily Blaine, Camas, Custer and Elmore Counties, but also includes minor parts of Ada, Butte, Gooding, Lincoln, and Minidoka Counties. These GIS data supersede those in the interpretive report: Worl, R.G. and Johnson, K.M., 1995, Geology and mineral deposits of the Hailey 1 degree x 2 degrees quadrangle and the western part of the Idaho Falls 1 degree x 2 degrees quadrangle, south-central Idaho - an overview: U.S. Geological Survey, Bulletin 2064-A, scale 1:250,000, https://pubs.usgs.gov/bul/b2064-a/.