Find ZIP codes info...

ZIP Code Lookup

ZIP Code Lookup

Find all types of zip code in America. Unique, Standar, PO Box, Military.

About Zip Codes

A Zip Code is a numeric code that the United States Postal Service uses to maintain a more efficient rout mail. ZIP stands for Zone Improvement Plan. At first the code was used by the USPS only, but after proving the efficiency of this method, the code was embraced by other shipping companies such as: United Parcel Service (UPS), Federal Express (FedEx), DHL, and others.

There are different types of Zip Codes, among them, you can find the Standard, the Military, the PO Box (that is an unique number issued for a specific business or brand), and the Unique or single high volume address.

In 1963 the USPS introduced a basic 5-digit format, after a trial period, they decided to add 4 more digits. The final formula was a ZIP+4 code, this way they improved the precision in the group's mailing.

When reading a ZIP code, first you have to understand that the first number represents a group of States. After this number, the rest of the digits are generally assigned from east to west. With some exemptions, when you observe the number 0, it indicates a place more to the east, and the 9 indicates one more to the west. Following this interpretation, reading the first 3 numbers, it will indicate a “Sectional Center Facility” (sec center). This sec center is the place where all the mail is processed and then sended to the post office near you.

ZIP Code by states

States ZIP codes

Military ZIP codes

Other territories ZIP codes

Most requested ZIP codes

Recent ZIP code Searches