DELIVERY - WestPac Area - CO-WY District - Mesa Verde National Park Post Office - Resume Operations

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.

USPS APIs Release Notes

For the latest updates, please review the USPS APIs Release Notes.

USPS® Approved Manufacturers of Mailing Containers for Adult Birds

A list of contact information for adult bird container manufacturers that have been certified by USPS.

Informational - USPS Webinar on AI, Direct Mail and Mailing Promotions

July 2026 Release Overview

Note: For the latest technical specifications, please see the July 2026 Price Change Release Notes as they are published. Mail.dat and Mail.XML updates required for this release. 

Pending Route Adjustment File

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

INFORMATIONAL: USPS Modernization through Package Equipment Upgrades in February and March 2026

PROCESSING AND DISTRIBUTION: USPS Closures Due to Weather Impacts Across the Northeastern United States

Periodicals Application Process FAQ