| zip5 | Zip code, 5 digits | First 5 digits of zip code | Beginning, sec.C3 |
| FIPS | State + County FIPS code | 2-digit State + 3-digit County FIPS code (Federal Information Processing Standard). See also U.S. Census Bureau State & County QuickFacts. | |
| CNTYNM | County name | County name. | |
| FIPSTATE | State FIPS | Two-letter state abbreviation based on State FIPS code | |
| MSA | Metropolitan Statistical Area | Metropolitan Statistical Area (NCCS file) (list) | |
| CMSA | Consolidated MSA | Consolidated Metropolitan Statistical Area - by definition is an MSA with one million population or more. Separate component areas (PMSAs) must be defined within an MSA for the entire area to be designated a CMSA (19 CMSAs as of 1995). (list) | |
| PMSA | Primary MSA | Primary Metropolitan Statistical Area - the component areas that comprise a CMSA (76 PMSAs as of 1995). (list) | |
| FILEYR | ZIP source year | Year of ZIP Code lookup file (03=2003 only, 06=2006 only, 0306=ZIP in 2003 and 2006 lookup files) | |
