FIPS county codes are a Federal Information Processing Standard for five-digit codes used to uniquely identify counties and county equivalents in the United States, certain U.S. possessions, and certain freely associated states. The first two digits are the FIPS state code and the last three are the county code within the state or possession. Federal Information Processing Standards (FIPS) are publicly announced standards developed by the U.S. Federal government for use by all (non-military) government agencies and by government contractors. ... A two-digit Federal Information Processing Standard (FIPS) code (FIPS 5-2) uniquely identifies a state, territory, or commonwealth within or of the U.S.. These codes are used by the U.S. Census Bureau, and in the Emergency Alert System, and were assigned by NIST. Additional numbers used with...

County FIPS codes in the United States are usually (with a few exceptions) in the same sequence as alphabetized county names within the state. They are usually (but not always) odd numbers, so that new or changed county names can be fit in their alphabetical sequence slot.

Lists of state and county FIPS codes for the United States can be found at http://www.epa.gov/enviro/html/codes/state.html[1] http://www.census.gov/geo/www/fips/fips65/download.html[2]