Contact Lists
02/12/2026
CASS™ Software Manufacturers Cycle O - (Expires July 31, 2028)
Contact Lists
02/12/2026
CASS™/MASS™ Certified Products Guide - All Sections Data Files Cycle O - (Expires July 31, 2028)

This document contains the certified vendors list for CASS™ and MASS™ products for Cycle O.

Data Files
02/12/2026
Z4 Info File

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

Data Files
02/12/2026
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
02/11/2026
INFORMATIONAL - USPS APIs System Deployment CR# TBD February 21, 2026
Announcements
02/11/2026
INFORMATIONAL - USPS APIs System Deployment March 1, 2026
Announcements
02/11/2026
INFORMATIONAL - USPS APIs System Deployment February 15, 2026
Release Notes
02/11/2026
Tracking API Access Control Changes Release Overview
Announcements
02/10/2026
INFORMATIONAL: USPS Ship (Package Platform) - [INCIDENT # 10397797] USPS Ship January Monthly Assessment Collections are Delayed
Presentations
02/10/2026
PCCAC: News You Need to Know From MTAC

 

https://usps.zoomgov.com/rec/share/dVCexGXMF6yLvnuvYhgUTaad1LGeVzq5wnLhayMM61B7KJWOs0OLuDWw7jHZ986K.8DuPlxtBw4Hoz62Y

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