BAS Code Lists

All federally recognized American Indian areas (AIA), counties (and equivalent areas), incorporated places, consolidated cities, and minor civil divisions (MCDs) are assigned and identified by unique Boundary and Annexation Survey (BAS) IDs. 

Please use the links below to determine the BAS ID for your government. 

American Indian Area Names and BAS Codes

Legal Government Names and BAS Codes

BAS Governments Summarized by State & Type (County, Place, MCD)

Page Last Revised - January 2, 2025