| zip5 | ZIP Code | Five-digit ZIP Code | |
| 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. | |
| MSA | Metro Statistical Area | Metropolitan Statistical Area (NCCS file) (list) | |
| STATECODE | FIPS state/territory | Two-digit FIPS state/territory code | |
| COUNTY | FIPS county code | Three-digit FIPS county code | |
| Y | Latitude of ZIP | Latitude (degrees) of the center (centroid) of ZIP Code | |
| X | Longitude of ZIP | Longitude (degrees) of the center (centroid) of ZIP Code | |
| ZIP_CLASS | ZIP Classification | ZIP Classification:P=PO Box, U=Unique (large orgs/businesses/bldgs), M=Military (APOs/FPOs), Blank=Standard/non-unique | |
| CITY | City / Org Name | Name of city/organization | Beginning, sec.C3 |
| STATE | State (2 letter abbr.) | Two-letter state abbreviation | |
| STATENAME | State / territory name | Full name of state/territory | |
| COUNTYNM | County / parish name | Name of county/parish | |
| AREACODE | Single Area Code | Single Area Code for ZIP Code | |
| AREACODES | Multiple Area Codes | Multiple Area Codes for ZIP Code | |
| TIMEZONE | Time Zone | Time Zone for ZIP Code | |
| GMTOFFSET | GMT Diff (hrs) of ZIP | Diff (hrs) between GMT and time zone for ZIP Code | |
| DST | Daylight Savings | ZIP Code obeys Daylight Savings: Y-Yes N-No | |
| PONAME | P.O. Name | USPS Post Office Name: same as City | |
| ALIAS_CITY | Alternate city names | Alternate names of city separated by || | |
| ALIAS_CITYN | Alternate local names | Local - alternate names of city separated by || | |
| SOURCE | ZIP Source File | ZIP Code Source File (SAS release of ZIP Code file) | |