41,552 ZIP Codes

USPS
41,552

ZIP Codes

There are 41,552 ZIP Codes in the country. They range from 00501, belonging to the Internal Revenue Service in Holtsville, NY, to 99950 in Ketchikan, AK. The easiest ZIP Code to remember? How about 12345, a unique ZIP Code for General Electric in Schenectady, NY.

* | Tags: Fun facts USPS Fact #306 | July 1, 2025

Quick! What’s that ZIP Code?

The Zoning Improvement Plan (ZIP) Code was launched in 1963 to better process and deliver increasing volumes of U.S. Mail. The first number in the five-digit ZIP Code represents a general geographic area of the nation, “0” in the east, moving
to “9” in the west. The next two numbers represent regional areas, and the final two identify specific Post Offices. In 1983, the ZIP+4 Code was introduced.