DELIVERY - Westpac Area – Arizona – New Mexico District Blue Post Office – Resume Operations

PROCESSING AND DISTRIBUTION - Update - Des Moines, IA Processing and Distribution Center (P&DC) Reopened

DELIVERY - Southern Area -Tennessee District - Copperhill Post Office (37317) Temporarily Suspended

INFORMATIONAL - PostalOne! Alert – November 15, 2026

INFORMATIONAL - Commercial System Releases – Week of November 14, 2026

November 15 2026 USPS Ship 31.0.0.0 Release Notes

November 15 2026 PostalOne! 64.1.3.0 Release Notes

DELIVERY - Central Area - Vining IA Post Office (52348) - Temporarily Suspending Operations

DELIVERY - Central Area - Compton IL RMPO 61318 - Closed Indefinitely 11.05.2026

PROCESSING AND DISTRIBUTION - Possible Delays – Des Moines, IA Processing and Distribution Center (P&DC)

PROCESSING AND DISTRIBUTION - Billings, MT Processing and Distribution Center (P&DC) Machine Upgrade

Known Issues List 11.3.2026

CASS™ Certified Products Guide: Residential Delivery Indicator Cycle O - (Expires July 31, 2028)

RDI™ Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)

This document outlines the CASS/MASS certified vendors list for RDI™ Cycle O.

CASS™ Certified Products Guide: M L O C R Mailers/Users Data File Cycle O - (Expires July 31, 2028)

CASS™ Certified Products Guide: M L O C R Mailers/Users Cycle O - (Expires July 31, 2028)

CASS™ Certified Products Guide: M L O C R Service Bureaus Data File Cycle O - (Expires July 31, 2028)

CASS™ Certified Products Guide: M L O C R Service Bureaus Cycle O - (Expires July 31, 2028)

CASS™ Certified Products Guide: M L O C R Hardware Manufacturers Data File Cycle O - (Expires July 31, 2028)

CASS™ Certified Products Guide: M L O C R Hardware Manufacturers Cycle O - (Expires July 31, 2028)

CASS™ Certified Products Guide: Z4CHANGE Data File Cycle O - (Expires July 31, 2028)

CASS™ Certified Products Guide: Z4CHANGE Cycle O - (Expires July 31, 2028)

CASS™ Certified Products Guide: Vendor/Service Licensees Data File Cycle O - (Expires July 31, 2028)

CASS™ Certified Products Guide: Vendor/Service Bureaus Licensees Cycle O - (Expires July 31, 2028)

CASS™ Certified Products Guide: DSF2® Licensees Data File Cycle O - (Expires July 31, 2028)

DSF2® Licensees Cycle O: Certified Products Guide - (Expires July 31, 2028)

DPV® Licensees Data File Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)

DPV® Licensees Cycle O: Certified Products Guide - (Expires July 31, 2028)

CASS™ Software Manufacturers Data File Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)

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.

PROCESSING AND DISTRIBUTION - Update - Central Processing Region - Louisville, KY (PDC) Delays

DELIVERY - Westpac Area – Arizona – New Mexico District Blue Post Office – Temporarily Closed

DELIVERY - International Resumption of Mail Service - Effective November 6, 2026

Online Postage Due Permit Creation

Enterprise Payment System (EPS) User Guide

Online Permit Creation Fact Sheet

Enterprise Payment System (EPS) FAQs

The Enterprise Payment System or EPS allows customers to pay for products and services through an Enterprise Payment Account (EPA) funded as an Automated Clearing House (ACH) Debit or Trust Account. The EPS payment account management provides enhanced security features, centralized balance and account management, and a self-service customer experience.

PCCAC National Sub-Committee Leadership Transitions and Invitation to Join

PTR2 Release Notes_DD_11_05_26

PROCESSING AND DISTRIBUTION - Update - Indianapolis, IN Regional Processing and Distribution Center (RPDC) Delays

USPS APIs Release Notes

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

MTAC UG-WG-TT Leadership Roster and Matrix

October 2026 Nixie Volume

This spreadsheet contains the UAA statistics for October 2026.

INFORMATIONAL - Commercial System Releases – November 5, 2026

INFORMATIONAL - USPS APIs System Release Notification November 12

Destination Entry Service Standard Directory

Combined Service Standard Directory-PRI