What is a ZIP Code?

A ZIP Code is a postal code used in the United States. It helps postal systems sort, route, and deliver mail more efficiently.

What ZIP stands for

ZIP stands for Zone Improvement Plan. A basic ZIP Code has five digits, and an extended ZIP+4 format adds four more digits for more specific delivery routing.

ZIP Code versus postal code

ZIP Code is the U.S. term. Postal code is the broader term used in many countries, and formats differ around the world.

ZIP Codes are practical addressing tools, not exact boundaries of neighborhoods or cities.