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.

ACS Tables: PARS 2025

This spreadsheet contains 12 tables outlining ACS volume and cost for UAA Mail from FY2025.

Base Tables: PARS 2025

This spreadsheet contains 44 base tables focusing on postal operations, cost, and volume of handling UAA mail from FY2025.

Class Tables: PARS 2025

This spreadsheet contains 64 class tables that provide cost and volume by class of mail, presort category, and shape from FY2025.

Volume Tables: PARS 2025

This spreadsheet contains 3 volume tables that provide summary data by class of mail, shape, presort category, and disposition of UAA Mail.

Undeliverable-as-Addressed (UAA) Mail Roll-Up 1998-2025

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.

***Updated - New Areas*** - Area District 5-digit ZIP Codes (AREADIST_ZIP5.TXT)

Automated Zone Indicator (AZI) Table

The AZI table lists each five-digit ZIP Code™ and is an indicator of the type of processing that typically takes place on letter mail destined for each ZIP Code. Each number in the file is a ZIP Code appended with a numeric zone indicator. The five numeric indicators are as follows:

1. Two Pass Zones: Automated two-step sector/segment at mail processing facilities
2. 876 Carrier Route Sort Zones: Automated incoming secondary carrier route sorting at plants
3. Carrier Route Barcode Sorter (CSBCS) Zones: Automated walk sequence sorting on CSBCS machines at delivery units
4. Delivery Barcode Sorter (DBCS) Zones: Automated walk sequence sorting on DBCS machines at plants [i.e., sectional center facilities (SCFs)] or at delivery units
5. Manual/Mechanized Zones: No automated sorting; no tracking code scans should be generated from facilities matched to these ZIP Codes