Data Files
05/11/2026
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
05/01/2026
April 2026 Nixie Volume

This spreadsheet contains the UAA statistics for April 2026.

Data Files
05/01/2026
ZIP Codes by Area and District codes

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

Data Files
04/30/2026
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
04/24/2026
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
04/07/2026
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.

Data Files
04/02/2026
Data Files
04/01/2026
March 2026 Nixie Volume

This spreadsheet contains the UAA statistics for March 2026.

Data Files
04/01/2026
Informed Visibility Mail Tracking & Reporting Machine Count

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

Data Files
03/27/2026
Labeling List Changes Effective May 1, 2026

Effective May 1, 2026, the Postal Service™ will revise Labeling List(s) L007, L012, L014, L016, L051, L201, and L606 to reflect changes in mail processing operations. Mailers are expected to label according to these revised lists for mailings inducted on or after the May 1, 2026, effective date through June 30, 2026, expiration date. The changes will be published in the Postal Bulletin, Issue #22700.

Data Files
03/02/2026
February 2026 Nixie Volume

This spreadsheet contains the UAA statistics for February 2026.

Data Files
02/27/2026
Undeliverable-as-Addressed (UAA) Mail Roll-Up 1998-2025

This spreadsheet provides a breakdown of Total UAA mail by mail class from FY1998 thru FY2025.

Data Files
02/25/2026
Labeling List Changes Effective April 1, 2026

Effective April 1, 2026, the Postal Service™ will revise Labeling List(s) L002, L005, L007, L012, L016, L051, L201, and L606 to reflect changes in mail processing operations. Mailers are expected to label according to these revised lists for mailings inducted on or after the April 1, 2026, effective date through May 31, 2026, expiration date. The changes will be published in the Postal Bulletin, Issue #22698.

Data Files
02/24/2026
Pending Route Adjustment File

This Excel sheet details route adjustments for February 2026 thru April 2026.

Data Files
02/02/2026
January 2026 Nixie Volume

This spreadsheet contains the UAA statistics for January 2026.

Data Files
01/27/2026
Updated List: Service Type Codes for Intelligent Mail® Package Barcode (IMpb)

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

Data Files
01/06/2026
ACS Tables: PARS 2025

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

Data Files
01/06/2026
Base Tables: PARS 2025

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

Data Files
01/06/2026
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.

Data Files
01/06/2026
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.

Data Files
01/02/2026
Data Files
01/02/2026
December 2025 Nixie Volume

This spreadsheet contains the UAA statistics for December 2025.

Data Files
12/29/2025
Labeling List Changes Effective February 1, 2026

Effective February 1, 2026, the Postal Service™ will revise Labeling List(s) L002, L005, L012, L016, L051, L201, and L606 to reflect changes in mail processing operations. Mailers are expected to label according to these revised lists for mailings inducted on or after the February 1, 2026, effective date through March 31, 2026, expiration date. The changes will be published in the Postal Bulletin, Issue #22694.