Data Files
02/13/2026
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
02/12/2026
Z4 Info File

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

Data Files
02/12/2026
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
02/09/2026
***Updated - New Areas*** - Area District 5-digit ZIP Codes (AREADIST_ZIP5.TXT)
Data Files
02/09/2026
City/State ZIP Code Weekly Compare
Data Files
02/09/2026
3 Digit ZIP/AISU Office List (AISUREPT.TXT)
Data Files
02/09/2026
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®.

Data Files
02/09/2026
AIS Congressional District File (CONG_DIST.TXT)
Data Files
02/09/2026
AIS County Name Table Layout (AISCNTY.TXT)
Data Files
02/09/2026
AMS County Name Table (COUNTY_NAME_TABLE.TXT)