Data Files
05/21/2026
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
05/20/2026
INFORMATIONAL - Updated 5-20-2026 - 2026 Labeling List and Mail Direction File (MDF) Timeline
Announcements
05/20/2026
DELIVERY - Diplomatic Post Office (DPO) May 20, 2026
Announcements
05/20/2026
INFORMATIONAL - USPS APIs System Release May 21, 2026
Technical Specifications
05/20/2026
Mail.xml Technical Specifications R64.0.0.0