User Guides
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USPS Verification of Periodicals Advertising Percentage – Alternate Marked Copy Program
User Guides
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Domestic Merchant Returns API: User Guide

This user guide provides examples of XML transactions to the USPS Merchant Returns web service and guidance for installation.

User Guides
08/25/2025
Enterprise Payment System (EPS) User Guide
User Guides
08/08/2025
Premium Forwarding Service Commercial External User Guide
User Guides
07/31/2025
Mailing and Shipping Solutions Center (MSSC) Topics

List of topics the MSSC can assist with. To reach the MSSC, email us at MSSC@usps.gov or call 1-877-672-0007 from 7:00AM – 7:00PM CT.

User Guides
07/25/2025
July 2025 PCC Membership Best Practices Guide
User Guides
07/24/2025
Informed Delivery Add-On Batch Upload Guide Video
User Guides
07/24/2025
Integrated Technology Batch Upload Guide Video
User Guides
07/24/2025
Integrated Technology Batch Upload Guide
User Guides
07/24/2025
Informed Delivery Add-On Batch Upload Guide