County lookup
What county am I in?
- Counties covered
- 3,144
- ZIP codes mapped
- 33,642
- Source
- US Census
- Cost
- Free
Quick answer
Enter your ZIP code and this page names the county it sits in, matched against the Census 2020 ZIP-to-county file covering all 33,642 ZIP Code Tabulation Areas. Or share your location and it names the county of the nearest tracked city. A county is the administrative layer above your city: it sets property tax rates, runs the courts, records deeds and issues many permits.
Find my county by ZIP code
Exact answer, from the Census ZIP-to-county relationship file.
Use my location instead
Matched in your browser — the reading never leaves your device.
The browser asks permission first and the reading stays on your device. Nothing is uploaded or stored.
Three ways to find your county
Three reliable ways to identify the county you are standing in.
- Look up your ZIP. Fastest and exact for the ~30,000 ZIPs that sit wholly inside one county.
- Check a public record. Your property tax bill, vehicle registration, voter card or recorded deed prints the issuing county.
- Open the county directory. Browse all 3,144 counties by state and see every ZIP code inside each one.
Why the county matters
What the county layer actually controls.
The county sets the property tax rate on your home, adds a local layer on top of the state sales tax, runs the trial courts and the recorder of deeds, and issues building, marriage and business permits. Two houses a mile apart in different counties can pay materially different property tax on the same assessed value. Check the property tax rates and sales tax stack for the county before you assume they match your neighbours'.
County FAQ
What people ask about counties and ZIP codes.
Can one ZIP code cross two counties?
Yes. ZIP codes are mail delivery routes and ignore county lines. This tool reports the county holding the largest share of the ZIP's land area — the assignment the Census publishes. For tax or legal purposes, use the county printed on your property record.
How many counties are there?
3,144 county-equivalents: counties, Louisiana parishes, Alaska boroughs and census areas, Virginia's independent cities, and Connecticut's nine planning regions.
Why does Connecticut behave differently?
The Census retired Connecticut's eight counties in 2022 and replaced them with nine planning regions. Connecticut ZIPs still carry the legacy county name in the relationship file, so the tool reports that name and says so rather than guessing a region.
Is my location sent anywhere?
No. The geolocation match runs in your browser against the coordinate table shipped with the page. The ZIP lookup sends only the five digits you type.
Sources & transparency
- US Census Bureau 2020 ZCTA-to-county relationship file — ZIP Code Tabulation Area to county assignment by land-area overlap
- US Census Bureau, American Community Survey 2019-2023 5-year estimates — ZIP and county population and median household income
Last reviewed August 2026. Figures are published for reference and can change; verify with the source agency before filing or contracting. How we build and check this data.