Data Files
04/16/2026
USPS Ship Data Dictionary

Detailed information on the USPS Ship (Formerly Package Platform) data elements available through the Informed Visibility Mail Tracking & Reporting (IV-MTR) application. Please note that items in bold text were updated or added recently.

Data Files
04/16/2026
Z4 Info File

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

Data Files
04/16/2026
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.

 

Data Files
04/15/2026
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.

Data Files
04/15/2026
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
04/13/2026
Data Files
04/13/2026
Cumulative Listing of ZIP Codes Covered by the LACS Database

This document provides a cumulative listing of ZIP Codes covered by the LACS database for LACSLink®.