USPS now offers official ZIP Code boundary polygons

USPS® ZIP Code Boundaries is a national ZIP Code™ map utilizing USPS delivery address and location information to ensure accurate boundaries. Temporal fluctuation is based on changing delivery distribution for new or changed delivery locations. Many industries, such as mapping, mailing, marketing, insurance, real estate, logistics, navigation, and transportation can benefit from access to the ZIP Code boundary data.

For example:

• As the ground truth for ZIP Code boundaries, users can incorporate these polygons as joint features or correct existing ZIP Code data as changes are made.
• As a tool for organizing and displaying demographic data, ZIP Codes serve as a support structure for real estate and insurance industries.
• ZIP Codes can serve as a proxy for the delivery location groupings for optimized routing.

USPS® ZIP Code Boundaries - Internal

Four quarterly updates.

USPS® ZIP Code Boundaries - Enterprise

Four quarterly updates with limited distribution to subsidiaries and partner companies.

USPS® ZIP Code Boundaries - Publication

Four quarterly updates with limited publication.