CASS™ Software Manufacturers Cycle O - (Expires July 31, 2028)

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.

Z4 Info File

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

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.

Priority Mail Next Day 5D5D

INFORMATIONAL - Scheduled Commercial Systems Activities (5.18.2025)

May 18, 2025 Release Notes

DELIVERY: Atlantic Area - ME-NH-VT District - Thetford Center Post Office (05075) - Temporarily Closed

eVS to USPS Ship Migration Tech Sheet

The Postal Service is retiring the electronic verification system (eVS). eVS customers must migrate to USPS Ship or USPS APIs by February 2025. This includes customers using Premium Forwarding Services Commercial (PFSC) and Click N Ship BusinessPro (CNBPro). This document outlines the differences between the two platforms and steps to migrate from eVS to USPS Ship.

eVS and USPS Ship Online Report and IV®-MTR Data Feed Comparison

eVS and USPS Ship Online Report and Informed Visibility® Mail Tracking & Reporting IV®-MTR Data Feed Comparison