Release Notes
11/14/2026
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.

Announcements
11/12/2026
INFORMATIONAL: U.S. Postal Service Recommends Shipping Price Adjustments for 2027
Announcements
11/12/2026
INFORMATIONAL: U.S. Postal Service Recommends Shipping Price Adjustments for 2027
Contact Lists
11/12/2026
CASS™ Certified Products Guide: Residential Delivery Indicator Cycle O - (Expires July 31, 2028)
Contact Lists
11/12/2026
RDI™ Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)

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

Contact Lists
11/12/2026
CASS™ Certified Products Guide: M L O C R Mailers/Users Data File Cycle O - (Expires July 31, 2028)
Contact Lists
11/12/2026
CASS™ Certified Products Guide: M L O C R Mailers/Users Cycle O - (Expires July 31, 2028)
Contact Lists
11/12/2026
CASS™ Certified Products Guide: M L O C R Service Bureaus Data File Cycle O - (Expires July 31, 2028)
Contact Lists
11/12/2026
CASS™ Certified Products Guide: M L O C R Service Bureaus Cycle O - (Expires July 31, 2028)
Contact Lists
11/12/2026
CASS™ Certified Products Guide: M L O C R Hardware Manufacturers Data File Cycle O - (Expires July 31, 2028)
Contact Lists
11/12/2026
CASS™ Certified Products Guide: M L O C R Hardware Manufacturers Cycle O - (Expires July 31, 2028)
Contact Lists
11/12/2026
CASS™ Certified Products Guide: Z4CHANGE Data File Cycle O - (Expires July 31, 2028)
Contact Lists
11/12/2026
CASS™ Certified Products Guide: Z4CHANGE Cycle O - (Expires July 31, 2028)
Contact Lists
11/12/2026
CASS™ Certified Products Guide: Vendor/Service Licensees Data File Cycle O - (Expires July 31, 2028)
Contact Lists
11/12/2026
CASS™ Certified Products Guide: Vendor/Service Bureaus Licensees Cycle O - (Expires July 31, 2028)
Contact Lists
11/12/2026
CASS™ Certified Products Guide: DSF2® Licensees Data File Cycle O - (Expires July 31, 2028)
Contact Lists
11/12/2026
DSF2® Licensees Cycle O: Certified Products Guide - (Expires July 31, 2028)
Contact Lists
11/12/2026
DPV® Licensees Data File Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)
Contact Lists
11/12/2026
DPV® Licensees Cycle O: Certified Products Guide - (Expires July 31, 2028)
Contact Lists
11/12/2026
CASS™ Software Manufacturers Data File Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)
Contact Lists
11/12/2026
CASS™ Software Manufacturers Cycle O - (Expires July 31, 2028)
Contact Lists
11/12/2026
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.

Applications/ Forms
11/12/2026
Informed Visibility® Mail Tracking & Reporting (IV®-MTR) Piece-Level One-Time Query Request

This form is to help users prepare to submit a one-time query for piece-level data, either on their own through the IV-MTR web application or assistance from the IV Solutions Center.

Data Files
11/12/2026
Informed Visibility® Mail Tracking & Reporting (IV®-MTR) Operation Codes List

This spreadsheet provides a list of operation codes (opcodes), also known as Scan Event Codes, for the IV-MTR application.

Data Files
11/12/2026
Z4 Info File

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