Informed Visibility Mail Tracking & Reporting Machine Count

List of US Postal Service machines by site, including a description of each machine.

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

Labeling List Changes Effective September 1, 2026

Effective September 1, 2026, the Postal Service™ will revise Labeling List(s) L007, L008, L012, L016, L201, L606, and L607 to reflect changes in mail processing operations. Mailers are expected to label according to these revised lists for mailings inducted on or after the September 1, 2026, effective date through October 31, 2026, expiration date. The changes will be published in the Postal Bulletin, Issue #22708.

 

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.

Undeliverable-as-Addressed (UAA) Statistics by Mailing Industry Quarterly Report (Q3 FY26)

ACS Nixie stats by industry for FY26 Q3.

June 2026 Nixie Volume

This spreadsheet contains the UAA statistics for June 2026.

ZIP Codes by Area and District codes

The Excel spreadsheet lists ZIP Codes with the associated Area and District Codes.  

Informed Delivery® Post-Campaign (IDPC) Data through IV-MTR® Data Dictionary

This document describes the Informed Delivery Post-Campaign (IDPC) data fields available through the IV-MTR application.

Updated List: Service Type Codes for Intelligent Mail® Package Barcode (IMpb)

This document provides the updated service type codes for  Intelligent Mail® Package Barcodes.

May 2026 Nixie Volume

This spreadsheet contains the UAA statistics for May 2026.