Contact Lists
02/22/2024
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
02/22/2024
Z4 Info File

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

Applications/ Forms
02/22/2024
Mail Service Provider (MSP) Application for Full-Service Certification

The application for enrollment in a voluntary program to become a certified Mail Service Provider. 

Data Files
02/22/2024
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.

 

Tech Guides
02/21/2024
Announcements
02/21/2024