DELIVERY: WestPac Area: CO-WY District - Hasty Post Office (81044) - Temporarily Closed

INFORMATIONAL - Business Customer Gateway Issues

INFORMATIONAL - RESOLVED - USPS Applications - INCIDENT 10942833 Intermittent Unavailability and Errors

INFORMATIONAL - Hawaii - Tropical Storm Lala – Operations Weather Advisory

INFORMATIONAL -UPDATE - PostalOne! Release – August 16, 2026

Business Acceptance Solutions & Major Mailer Support Directory

This document provides a contact list for Business Acceptance Solutions (formerly Business Mailer Support) & Major Mailer Support

MPE (Mail Processing Equipment) Service Provider Licensees

Marketing contact information for certified Mail Processing Equipment (MPE) licensees 

PCCAC Certification Webinar-Beyond the Stamp: Unlocking the Power of Marketing Mail with Zach Bowden

https://usps.zoomgov.com/rec/share/M8XcQJAuA3G2nw5PNXY5tuOd0a5YLGFV04x5KqF5fEwwQKA-p09zQ6zXnuSha_RM.z-oSaN6SmJXz-dWF

Passcode: z1@T4?Lp

PROCESSING AND DISTRIBUTION - Update - Central Region – Upper Midwest and Ohio Valley- Severe Weather Impacts

INFORMATIONAL - Cancellation of Daily Addressing and NCOA + Webinars

DELIVERY - WestPac Area - Washington District - Mead and Nine Mile Falls Post Offices – Resume Operations

PROCESSING AND DISTRIBUTION - Central Region – Upper Midwest and Ohio Valley- Severe Weather Impacts

Addresses API - Tech Sheet

Known Issues List 8.6.2026

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.

INFORMATIONAL - USPS APIs System Release Notification – August 31, 2026

DELIVERY - La Villa Post Office (78562) - Temporarily Suspended

DELIVERY: WestPac Area - NV-UT District - Nixon Post Office (89424) - Office Temporarily Closed

Request to Lead or Participate - MTAC User Group and Work Group

USPS PTR2 API Known Issues

Mailers Technical Advisory Committee (MTAC) Membership Roster and Vacancies

Informed Visibility® Mail Tracking & Reporting (IV®-MTR) Development Tracker

This document provides a list of active IV-MTR work to be as well as items completed in FY25.

*Please note, Postal Pro is the only source for a current IV-MTR Development log as updates will be made on an ongoing basis.

USPS APIs Release Notes

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

Informed Visibility® Mail Tracking & Reporting (IV®-MTR) Release Notes

These release notes summarize new features and enhancements implemented in deployments to the IV-MTR application.

Mini Cafe Part Two - Informed Delivery for PCCs

Mail Service Provider (MSP) - Full-Service Certified Mailers

A Mail Service Provider (MSP) offers a variety of solutions to prepare and present Full-Service presort mailings. For more information regarding Certified MSPs, please follow this link: https://postalpro.usps.com/full-service-cert/fact-sheet

Modernization of Address Processing with APIs - Q & A

USPS Addresses API - Completing PS Form 3553

INFORMATIONAL - Commercial System Releases – Week of August 15, 2026

INFORMATIONAL - PostalOne! Release – August 16, 2026