Announcements
01/02/2026
INFORMATIONAL – Officer Announcement – Jason DeChambeau as Acting Vice President of Processing Operations
Data Files
01/02/2026
Undeliverable-as-Addressed (UAA) Statistics by Mailing Industry Quarterly Report (Q1 FY26)

ACS Nixie stats by industry for FY26 Q1.

Data Files
01/02/2026
December 2025 Nixie Volume

This spreadsheet contains the UAA statistics for December 2025.

Data Files
01/02/2026
Z4 Info File

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

Tech Guides
01/02/2026
Labeling Lists Technical Guide

The Labeling Lists data product assists mailers with presorting mail. It provides active, originating 3- and 5-digit ZIP Code™ data along with their destination locations [including city/state/ZIP Code] for labeling purposes. The product contains complete data files of each list found online via Postal Explorer® at https://pe.usps.com. Updates to the Labeling Lists are also published in the Postal Bulletin.

Data Files
01/02/2026
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.

 

Announcements
01/01/2026
INFORMATIONAL - Tracking API Provisioning Notification
Publications
01/01/2026
Destination Entry Service Standard Directory
Publications
01/01/2026
Combined Service Standard Directory-PRI
Publications
01/01/2026
Supplemental Service Standard Directory-PRI