US ZIP Code System

The introduction of the ZIP Code system revolutionized mail delivery in the United States by streamlining the sorting and distribution process.

The Zone Improvement Plan (ZIP) Code system was introduced by the United States Postal Service (USPS) on July 1, 1963. This system was implemented by Postmaster General J. Edward Day, who recognized the need for a more efficient method of sorting and delivering the growing volume of mail in the country.

The ZIP Code system is a five-digit code that identifies a specific geographic area within the United States. The first three digits represent a Sectional Center Facility (SCF), a central mail processing facility serving a particular region. The next two digits represent a specific region’s post office or delivery area.

An extended ZIP+4 Code was introduced in 1983 to improve the system’s efficiency further. The additional four digits help identify a more precise location, such as a particular building or group of apartments.

Introducing the ZIP Code system greatly improved the speed and accuracy of mail delivery in the United States. It allowed for the automation of mail sorting and enabled the USPS to handle the ever-increasing volume of mail more effectively. Today, the ZIP Code system remains an essential part of the postal service infrastructure in the United States, and it is widely used for various purposes beyond mail delivery, including demographic analysis and marketing.