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ZIP codes by county or city

Pick a state, then one of its counties or cities, and get every ZIP code in it on the map and in a list with its population. 28% of ZIP codes cross a county line, so each one shows how much of it lies inside.

By the All Map Tools Team

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County

Travis County, TX

 

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Hover over or tap a ZIP code

  • Entirely inside (99%+ of its land)
  • Shared, mostly inside
  • Shared, mostly outside

ZIP codes are Census ZCTAs (2020 boundaries); population from the ACS 2020–2024. Residents inside a county are estimated for shared ZIPs.

ZIP codes (0)

How to use it

Choose a state, then “A county” or “A city or town”, and type its name: the lists of the 3,144 counties and 31,608 cities, towns and CDPs are built into the page, one state at a time. It opens on Travis County, TX, which has 60 ZIP codes, 23 of them shared with other counties.

The map draws each ZIP code’s area in color: green if it lies entirely inside, yellow if it’s shared but mostly inside, orange if most of it is outside. Hover or tap one to see its population and how much of it falls inside; the list next to the map has the same ZIP codes, sortable by number, population or share.

“Download CSV” gives you every ZIP code with its main city, population, land area, share inside and coordinates. “Copy ZIP codes” copies the list separated by commas, ready to paste in a form or a spreadsheet, and “Copy one per line” does it one under another. “Copy link” saves what you picked in the address.

Why a ZIP code can be in two counties

ZIP codes are delivery routes drawn by the Postal Service, not political boundaries, so they ignore county lines. Of the 33,642 ZIP codes with an area of their own, 9,399 have at least 1% of their land in more than one county, and 117 even cross a state line. A list that puts each ZIP code in a single county leaves out or misplaces all of them.

That’s why each ZIP code here comes with the share of its land inside the county or city, exact from the Census relationship files. For counties you also get how many of its residents live inside: the whole ZIP if it’s entirely in the county, and an estimate for shared ones. ZIP codes with under 1% of their land inside are usually just touching the border; they’re hidden unless you tick the box above the list.

Los Angeles County, CA has the most ZIP codes of any county, 301. The 538 most populous counties also have a page of their own with a printable map and the full table.

Where the data comes from

Everything is from the U.S. Census Bureau and in the public domain. The ZIP codes are the ZIP Code Tabulation Areas (ZCTAs) of the 2020 census, the areas the Census draws to approximate USPS ZIP codes; ZIPs with no area of their own, like PO boxes and single buildings, aren’t included. Which ZIP codes touch each county and city, and how much land they share, comes from the 2020 relationship files (in Connecticut, from the 2022 file for its towns, which fall within its new planning regions). Population is the American Community Survey 2020–2024 five-year estimate.

The residents of a shared ZIP code are split between counties using its census tracts: the people of each tract are spread over the land it shares with the ZIP code, and the result is scaled to the ZIP code’s population. The areas on the map come live from the Census TIGERweb map service; if it doesn’t answer, the ZIP codes show as points.

ZIP codes in each state

Each state has a page with a map of its counties, how many ZIP codes each one has and the full list. All states and the counties with the most ZIP codes.

Frequently asked questions

How many ZIP codes are in a county?

It ranges from one to 301 (Los Angeles County, CA). Pick a county to see its full list, with the ones it shares with its neighbors.

Can a ZIP code be in more than one county?

Yes: 28% of them are. The list shows the share of each ZIP code’s land inside the county, and the map colors the shared ones yellow or orange.

Why is a ZIP code I know missing?

Because it has no area of its own: PO box ZIPs, single buildings and some large companies get a ZIP code from the Postal Service but no ZCTA from the Census. Those can’t be drawn on a map.

How do I get the ZIP codes of a city?

Choose “A city or town” and type its name. Big cities often spread over several counties; the list gives every ZIP code that touches the city limits, with the share of its land inside.

Can I use the list in Excel or a CRM?

Yes. Download the CSV, or copy the ZIP codes separated by commas or one per line. The data is public domain from the Census Bureau.

Related tools

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County lookup by address Type any US address to see which county and state it’s in, with the county drawn on the map. What is my ZIP code? Get the ZIP code for where you are right now or for any US address, shown on the map. What state am I in? Find out which US state you’re in from your location, useful on road trips and near state lines. What county am I in? See which US county you’re in right now, along with its state, straight from your location. What country am I in? Check which country you’re in from your location, handy near a border or when you’ve just landed. What city am I in? Find out which city or town you’re in right now, with its region and country, from your location.

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