This USGS data release documents coarse ranges for 123 fish species in the conterminous United States for level 8 hydrologic units from the Watershed Boundary Dataset (WBD). These range maps were derived by combining known fish occurrence information from four data sources: point occurrences from the Aquatic Gap Analysis Project (AGAP) fish database, point occurrences from the IchthyMaps dataset, point occurrences from the Global Biodiversity Information Facility (GBIF), and HUC-8 level range maps developed by NatureServe. Data can be linked to geospatial units of the WBD using the HUC8 field. Data are provided in comma separated value (CSV) and zipped Parquet file formats. Parquet file format is provided to help facilitate faster download and read capabilities when using compatible packages in coding languages such as R and Python.