On July 1, 1963, zip codes were introduced to improve mail delivery in the United States
July 1, 2025
An event every year that begins at 12:00 am on day 1 of July, repeating indefinitely
On July 1, 1963, zip codes were introduced to improve mail delivery in the United States. 📬📨💌📬 This aim is reflected in the name – the “ZIP” in “zip codes” is an abbreviation for “zone improvement plan.”
Did you know? You may know that zip code numbers get higher as one moves geographically from east to west, but did you know that each number in your zip code means something?
The first number indicates one of ten regions of the United States. The second and third digits, indicate the state and major postal destination (such as a city post office). The last two digits relate to a smaller destination, such as your local post office. (Most people do not write out additional digits, but these oft-forgotten extra numbers can help pinpoint neighborhoods even further.)
The Artist’s Letter Rack, William Harnett, 1879
-Written by Anna Zemaitaitis, Communications and Design Officer