US state FIPS code

The code was FIPS 5-2 until the National Institute of Standards and Technology withdrew that standard in 2008. It continues as INCITS 38 under the InterNational Committee for Information Technology Standards, and the Census Bureau assigns and publishes it. The Bureau's own code lists note that INCITS codes are formerly known as FIPS codes, which is why the old name survives everywhere in practice.

Two digits, assigned alphabetically: Alabama 01, Wyoming 56, with the District of Columbia and the territories interleaved. The leading zero is part of the code, and storing it as a number is the most common way these values are corrupted.

At state level there is no parent code to prefix, so the US state GEOID is the same two digits under a different name.