US ZIP Codes
Canada PostalFind Any ZIP Code or Postal Code in Seconds
A ZIP code looks simple enough, five digits, nothing more. But get one number wrong and a package ends up three states away from where it should. That's the whole reason USZipLookup exists: to give shippers, movers, developers, and researchers a fast, dependable way to confirm postal information before it becomes a problem instead of after.
This site covers two postal systems. On the US side, you'll find every ZIP code across all 50 states, tied to city, county, and geographic data. On the Canadian side, you'll find postal codes across every province and territory, mapped to the same kind of detail. Type a ZIP code, a postal code, or a city name into the search bar, and you'll get a result built from data that's checked on a regular schedule, not scraped once and left to rot.
About US ZIP Codes
The ZIP code system dates back to 1963, when the Post Office Department needed a faster way to sort a growing volume of mail. "ZIP" stands for Zone Improvement Plan, and the five-digit structure was built around a simple idea: group addresses geographically so machines and mail clerks could route them without reading every line of an address by hand.
The first digit places an address in one of ten broad national zones, running roughly west to east, 0 covers parts of the Northeast, 9 covers the Pacific coast. From there, the second and third digits identify a sectional center, usually tied to a major distribution hub, and the last two digits get down to a specific town or delivery zone.
What trips people up is assuming a ZIP code lines up with a city limit or county border. It usually doesn't. A ZIP code is a mail-routing tool first, not a legal boundary, so a single code can straddle two counties, and a mid-sized city can be sliced into a dozen separate codes depending on population density and carrier routes.
About Canadian Postal Codes
Canada Post's system takes a different approach: six characters, alternating letter-number-letter, then a space, then number-letter-number, something like K1A 0B1. That alphanumeric format packs far more unique combinations into six characters than a numeric-only system could manage, which matters in a country with a small population spread across a massive land area.
The first character tells you the postal district. Toronto addresses start with M. Ottawa and the surrounding region use K. British Columbia uses V. Alberta uses T. The first three characters together form what Canada Post calls a Forward Sortation Area, narrowing things down to a city or a large chunk of a city. The last three characters, the Local Delivery Unit, get specific enough to sometimes mean a single office tower or apartment complex.
One detail worth knowing: the letters D, F, I, O, Q, and U never appear in a Canadian postal code. Canada Post excluded them because they're too easy to confuse with numbers or other letters, especially in handwriting.
How the Search Works
Type in what you know. If it's a ZIP code or postal code, you'll land on a page built around that specific location - city, region, coordinates, and nearby areas. If it's a city name, the search runs the other direction and pulls up every code associated with that place, which matters more than people expect. Search "Chicago" and you won't get one ZIP code back, you'll get dozens, because a city that size has its mail routed through many separate zones.
Every location page pulls together what's actually useful: the code itself, city and state or province, county where it applies, latitude and longitude, an estimated population figure, and a list of neighboring codes. None of that requires digging through a government PDF or cross-referencing three different sites.
ZIP Code Distance Calculator
Knowing a ZIP code is one thing. Knowing how far it is from another one is a separate, equally common question and it's the reason we built a standalone Distance Calculator. Enter two US ZIP codes and get a distance estimate based on each code's geographic coordinates.
It's a small tool, but it gets used for surprisingly practical things: a landscaping business figuring out whether a job three towns over is worth the drive, a delivery company estimating route length before committing a driver to it, a home buyer checking how far a listing actually sits from their office. None of that requires a full mapping application - just a fast, rough answer.
Browse by State
If you already know which state you're interested in, browsing beats searching. Every state page in our US ZIP Code Directory lists the cities and ZIP codes within that state, organized so you can scan a whole region at once rather than looking up one code at a time.
This is the better approach if you're comparing ZIP codes across a metro area, building out a regional sales territory, or just trying to get a feel for how a state's postal codes are distributed between its cities and rural stretches. States like California and Texas carry thousands of individual codes; smaller states like Delaware or Rhode Island carry a fraction of that.
Browse by Province
The same logic applies north of the border. Our Canada Postal Code Directory breaks down every province and territory - Ontario, Quebec, British Columbia, Alberta, and the rest into their component cities and postal codes.
Ontario and Quebec carry the largest share of Canada's postal codes by a wide margin, simply because that's where most of the population lives. The northern territories - Yukon, Northwest Territories, Nunavut, carry far fewer codes, each one often covering a much larger physical area than an urban code would.
Why USZipLookup
There's no shortage of ZIP code lookup tools online, so it's fair to ask what sets this one apart.
The data gets checked, not just published once. Postal boundaries shift, new developments get their own codes, some rural codes get merged, cities occasionally get split into additional zones as they grow. We review our database on a regular cycle instead of treating it as a static file from launch day.
Both countries, one interface. Plenty of sites handle US ZIP codes well. Fewer handle Canadian postal codes with the same depth. Having both in one place matters for anyone dealing with cross-border shipping or addresses on both sides of the line.
No dead ends. A search for a ZIP code returns location data. A search for a city returns every relevant code. Either direction gets you somewhere useful instead of a single flat result.
Built for actual use, not just browsing. The Distance Calculator, the state and province directories, and the individual location pages are designed around real tasks, confirming an address, planning a route, researching a market, rather than existing purely to rank for a keyword.
From the Blog
Postal systems have more depth than most people assume, and our blog digs into that, how ZIP codes get assigned, why some cities have dozens of codes while others have one, what a ZIP+4 extension actually does, how Canadian FSAs get used in market research, and practical guidance on formatting addresses correctly for both countries. If you want the mechanics behind the lookup tool, that's where to find them.
Where ZIP and Postal Code Data Actually Gets Used
It's worth spelling out why this data matters beyond the obvious mailing use case, because most people underestimate how many everyday decisions run through a ZIP or postal code somewhere in the background.
Retailers use it to calculate shipping cost and delivery windows before a customer even checks out. Auto and home insurers use it as one input in pricing a policy, since claims history and risk vary meaningfully by area. Banks and lenders reference it during underwriting. Streaming services and online retailers use it to determine regional pricing and content availability. School district assignment, in many US states, runs almost entirely on address-to-ZIP mapping. None of this is new, exactly, but it explains why getting the code wrong, even by a single digit can ripple into something bigger than a misdelivered letter.
For businesses specifically, a wrong ZIP code on a shipping label can misroute a package to the wrong regional sorting facility, adding days to a delivery that should have taken one. On the data side, a mismatched ZIP-to-city pairing in a customer database can throw off everything from tax calculations to marketing segmentation, and these errors tend to be invisible until something forces them to the surface, a bounced shipment, a rejected payment, a customer complaint.
A Few Things People Get Wrong
After looking at enough searches and support questions over time, a handful of recurring misconceptions stand out:
- Assuming a ZIP code maps to a single town. Plenty of ZIP codes cover several small unincorporated communities at once, especially in rural areas where population density doesn't justify separate codes.
- Treating US and Canadian formats as interchangeable. A five-digit numeric field will silently reject or mangle a six-character Canadian postal code if a form wasn't built to handle both, which is a common and avoidable bug in address forms.
- Ignoring ZIP+4 when it would actually help. For businesses sending high volumes of mail, the extended ZIP+4 code can shave real time off delivery by skipping a manual sorting step, it's underused mostly because people don't know it's there.
- Assuming ZIP code data never changes. New residential developments, decommissioned rural routes, and postal service reorganizations all shift boundaries over time. Data that was accurate five years ago isn't guaranteed to be accurate today.
Frequently Asked Questions
Q. What is a ZIP code?
- A ZIP code is a five-digit number the US Postal Service uses to route mail to a specific geographic delivery area. Beyond mailing, it's become a standard reference point for shipping calculations, market research, and location-based services of all kinds.
Q. What is a Canadian postal code?
- It's a six-character code - three letters and three numbers, alternating that Canada Post uses to identify a delivery area, which can range from an entire small town to a single building in a dense city.
Q. Can I search by city instead of by code?
- Yes. Enter a city name and the search returns every ZIP code or postal code tied to that location, which is often more useful than knowing just one code, especially for larger cities.
Q. Is there a cost to use USZipLookup?
- No. Search, the state and province directories, and the Distance Calculator are all free, with no account or sign-up required.
Q. How current is your data?
- We review it on a regular schedule to reflect changes from USPS and Canada Post. For anything legally or financially critical, always confirm directly with the postal authority - we're a reference tool, not the system of record.
Q. Why does one city have so many ZIP codes?
- Population density drives it. More residents and more mail volume mean a city gets split into smaller delivery zones so no single route gets overloaded. A town of 2,000 people might need just one code; a city of two million could need over a hundred.
Q. What's the real difference between a ZIP code and a postal code?
- Beyond the name, it's the format. ZIP codes are five digits, no letters. Canadian postal codes mix three letters and three numbers. Both exist to do the same basic job - get mail to the right place - but the systems were built independently and don't translate directly into one another.
Q. Can I find the distance btw. a US ZIP and a Canadian postal code?
- Not currently. The Distance Calculator is built around US ZIP code coordinates specifically. Cross-border distance calculations aren't supported yet.
Get Started
Search for a ZIP code, a postal code, or a city above, or head straight to the US ZIP Code Directory or Canada Postal Code Directory if you'd rather browse by state or province. If you need to compare two locations, the Distance Calculator will get you an estimate in seconds, and the blog is there if you want to understand the systems behind the numbers.
# US ZIP Code & Canadian Postal Code Lookup , # US & Canada ZIP Code Lookup - Free Postal Code Finder