Publications
10/01/2026
3D Base Service Standard Directory
Data Files
10/01/2026
Z4 Info File

A downloadable ZIP file containing information related to the Z4 Info File

Data Files
10/01/2026
Early Warning System (EWS002C0.ZIP)

This file is the EWS production file and is updated weekly. This file contains the Early Warning System data file for the CASS™ and MASS™ certification process.

 

Announcements
09/30/2026
INFORMATIONAL - USPS APIs System Release Notification - October 14, 2026
Announcements
09/30/2026
INFORMATIONAL - USPS Expands Addressing and Geospatial Data Offerings
Announcements
09/30/2026
DELIVERY - International Resumption of Mail Service - Effective October 2, 2026
Announcements
09/30/2026
INFORMATIONAL - Mail Spoken Here - September Issue
User Guides
09/30/2026
Provisioning EMAS API Invoices Data in Informed Visibility® Mail Tracking & Reporting (IV®-MTR)

This guide provides instructions for receiving EMAS API Invoices data through the IV Mail Tracking & Reporting application.

Release Notes
09/30/2026
USPS APIs Release Notes

For the latest updates, please review the USPS APIs Release Notes.

Announcements
09/29/2026
INFORMATIONAL: REMINDER: Electronic Verification System (eVS) Retirement