Basic City and County Zip Code Database

This dataset allows you to link cities and counties to their appropriate zip code.  This database has a unique city assigned to each 5 digit zip code, based on the USPS preferred mailing city for that 5 digit zip code destination.  The Basic City and County Zip Code Database allows you to:

• Find out what zip codes are in which cities
• Find out what zip codes are in which counties
• Find out what FIPs / ANSI codes are associated with each zip code
• Find out what zip codes are in each state
• Find out what the primary city is for each zip code
• Build robust address verification tools
• Create customized, zip code level demographic files

Our Basic City and County Zip Code Database has over 40 thousand 5 digit zip code records and is available for instant download in a simple .CSV file which can be imported into virtually every database available.

Data fields and definitions

The following are the fields included in the Basic City and County Zip Code Database.   The rows are unique by 5 digit zip code.  The database contains over 42 thousand records.

Example layout and records

Each zip code database comes in a flat file layout in .CSV (comma separated values.)  The first row is the header row.  The table below is an example of a few rows of the data.

About our zip code data

We are zip code data specialists licensed to sell zip code data by the USPS.  We update every record in our zip code databases monthly.  You will always receive the latest and most up-to-date zip code data - guaranteed. Every file is hand edited to create the most accurate zip code data available.

We’ve built our 5 digit zip code database from data we receive under license from the United States Postal Service.  Just like the postal service, we start from the bottom up with detailed, house level Zip+4 data. The zip code datasets we receive from the postal service contain over 80 million rows of data. As our IT guy said, to paraphrase the immortal words of Roy Scheider as Brody in Jaws, "I think you'll need a bigger computer!"

Because of the detailed nature of the USPS zip code data, we have to conduct an exhaustive analysis of the data to get it into a format which is actually usable for everyone who is not a mailman. (In layman's terms, we "crunch" the database.) This produces a set of files which are actually manageable and extract the most useful data elements you would want to use from zip code data to link to your datasets or use in your applications.

And because all of this changes so frequently, we do all our analysis each month to ensure that we are delivering the best quality data in the easiest to use format straight to you.

Our guarantee

We believe our zip code data is best in the business and stand by it unconditionally. We are licensed by the USPS to sell their zip code datasets. We have a rigorous process to scrub the zip code data and make it usable in a business and programming context. We offer a satisfaction guarantee on all our products, no questions asked. We are proud of what we do and hope our efforts help you get to insight faster and more accurately.