Represents a broad geographic area of the country (e.g., "0" for the Northeast, "9" for the West Coast).
Use all capital letters and avoid punctuation like periods or commas. USPS.zip
Introduced on , the ZIP ( Zone Improvement Plan ) code was designed to modernize mail delivery by enabling automated sorting. Before its adoption, mail passed through 17 sorting steps; the code reduced this significantly by providing a geographic "map" within a few digits. The 5-Digit Core: Represents a broad geographic area of the country (e
To ensure mail arrives quickly and is not returned to sender, the USPS Official Website recommends: Before its adoption, mail passed through 17 sorting
Launched in 1983 , this adds a hyphen and four extra digits to identify even smaller units like a specific city block, an office building, or even a single floor within a skyscraper. Digital "USPS.zip" Files
Pinpoint specific post offices or delivery zones within that region.
The ZIP code should always follow the state abbreviation on the last line of the address block. How to Send a Letter or Postcard: Domestic - USPS