ZIP Code to County Finder
Enter a 5-digit U.S. ZIP Code to see the Census ZIP Code Tabulation Area and every county it intersects.
ZIP 00000
Map data © OpenStreetMap contributors. ZCTA and county geography: U.S. Census Bureau TIGERweb.
ZIP Codes and counties do not always match one-to-one
USPS ZIP Codes are designed for mail delivery, not as legal geographic boundaries. A ZIP Code can cross county lines, and some USPS ZIP Codes do not correspond to a Census ZIP Code Tabulation Area.
This finder uses Census ZIP Code Tabulation Areas, commonly called ZCTAs, for geographic analysis. When a ZCTA intersects more than one county, County Map Pro lists all intersecting counties instead of forcing a single answer. To look up an identifier separately, use the County FIPS Code Lookup.
What is a ZCTA?
A ZIP Code Tabulation Area is a Census Bureau geographic product designed to approximate the geographic distribution of USPS ZIP Codes for mapping and statistical analysis. It is not the same thing as an official USPS delivery route.
Frequently asked questions
Can one ZIP Code be in two counties?
Yes. Postal delivery areas can cross county boundaries. This tool checks the Census ZCTA against county geography and can return multiple counties.
Why does a valid ZIP Code sometimes return no ZCTA?
Some USPS ZIP Codes, including certain PO Box or unique ZIP Codes, may not have a corresponding Census ZCTA because ZCTAs are generalized geographic areas rather than a complete USPS ZIP Code directory.
Should I use this for legal or property decisions?
Use it as a geographic reference. For taxes, voting, property boundaries, emergency services, or legal matters, confirm the county with the appropriate local government or official parcel records.