Code definitions: FIPS, MSA, CMSA, PMSA, Census Block / Tract, and more!

Code definitions

Understanding the common codes use to delineate geographic and demographic information can be quite complicated. This guide can help get you straight!

FIPS codes and ANSI codes

FIPS stands for Federal Information Processing Standards. The original FIPS codes were issued by the National Institute of Standards and Technology (NIST). These codes were related to states, counties, American Indian and Alaska Native areas, and other named places (like county subdivisions). FIPS codes have been replaced by ANSI codes, which stands for American National Standards Institute. Basically everyone still refers to them as FIPS codes and they work just about the same.

The codes are 5 digits, two for the state and 3 for the county.  They are generally alphabetically ordered.

Here's an example of a few FIPS / ANSI codes for Alabama to give you a feel for how they work:

A fully updated list of FIPS / ANSI codes can be downloaded immediately from our FIPS / ANSI code database product.  FIPS / ANSI codes are also included in our regular city, county and state zip code databases and our extended city, county and state zip code databases.

CBSA, MSA, and PMSA codes

The Census has created a set of codes that refer to core statistical areas, and are often tabulated as breakouts with very interesting demographic data reports.  We use these codes with our Zip Code Databases to report core demographic data at the zip code level.  But nothing can be more confusing than trying to understand the definitions of these codes -- the definitions have changed over time, and people often use the codes interachangably.

A CBSA is a Core Based Statistical Area (CBSA).  By definition, this is a statistical geographic entity consisting of the county or counties associated with at least one core (urbanized area or urban cluster) of at least 10,000 population, plus adjacent counties having a high degree of social and economic integration with the core as measured through commuting ties with the counties containing the core. Metropolitan and Micropolitan Statistical Areas are the two categories of Core Based Statistical Areas.