03/11/2026
Merchant Onboarding and Authorization Tech Guide
Merchants need to follow a two-step process to authorize a Label Provider to generate shipping labels on their behalf.
1. Log in or create a USPS business account on the Customer Onboarding Portal (COP) to get Customer Registration ID (CRID), Mailer ID (MID), and Enterprise Payment Account (EPA). A CRID is a unique identifier for your company. A MID is another identifier which can be part of the barcode on a piece of mail.
2. Authorize Label Provider in COP. Before the merchant’s account can be used by Label Provider, Label Provider must be authorized. This will also enable Label Provider to generate package labels on behalf of NSA Holders at their NSA rates.
03/10/2026
01/09/2026
01/06/2026
01/06/2026
USPS Ship Tech Sheet
USPS Ship is a modernized platform enabling commercial package payment, verification, and end-to-end visibility for a wide array of domestic and international products.
01/02/2026
Labeling Lists Technical Guide
The Labeling Lists data product assists mailers with presorting mail. It provides active, originating 3- and 5-digit ZIP Code™ data along with their destination locations [including city/state/ZIP Code] for labeling purposes. The product contains complete data files of each list found online via Postal Explorer® at https://pe.usps.com. Updates to the Labeling Lists are also published in the Postal Bulletin.
11/26/2025
PostalOne! Release 63.0.0.0 Mail.XML TEM WSDLs
This ZIP file contains the Web Services Description Language (WSDL) and XML Schema Definition (XSD) files for Mail.XML™ TEM Release 63.0.0.0
11/26/2025
11/26/2025
PostalOne! Release 63.0.0.0 Mail.XML PROD WSDLs
This ZIP file contains the Web Services Description Language (WSDL) and XML Schema Definition (XSD) files for Mail.XML™ PROD Release 63.0.0.0
11/26/2025
PostalOne! Release 63.0.0.0 Mail.XML CAT WSDLs
This ZIP file contains the Web Services Description Language (WSDL) and XML Schema Definition (XSD) files for Mail.XML™ CAT Release 63.0.0.0
10/06/2025
10/06/2025
Intelligent Mail Container Barcode Technical Specifications
Technical specifications for printing the USPS Intelligent Mail® Container barcode (IM™ Container barcode). The Intelligent Mail Container barcode is used on mailer-generated pallet labels to uniquely identify pallets and similar containers (i.e. All Purpose Containers, hampers, pallet boxes, etc.) in addition to identifying the mail owner.
07/24/2025
07/07/2025
Intelligent Mail Tray Label Technical Fact Sheet
This document provides fact sheet providing technical specifications on the acquisition, implementation, and benefits of the Intelligent Mail Tray Label.
06/18/2025
PostalOne! Release 62.0.0.0 Mail.XML CAT WSDLs
This ZIP file contains the Web Services Description Language (WSDL) and XML Schema Definition (XSD) files for Mail.XML™ CAT Release 62.0.0.0
06/18/2025
06/18/2025
PostalOne! Release 62.0.0.0 Mail.XML TEM WSDLs
This ZIP file contains the Web Services Description Language (WSDL) and XML Schema Definition (XSD) files for Mail.XML™ TEM Release 62.0.0.0
06/18/2025
PostalOne! Release 62.0.0.0 Mail.XML PROD WSDLs
This ZIP file contains the Web Services Description Language (WSDL) and XML Schema Definition (XSD) files for Mail.XML™ PROD Release 62.0.0.0
06/13/2025
Informed Delivery Mail.XML Mailer Guide
This is a guide for submitting campaigns to PostalOne! via Mail.XML electronic documentation (eDoc).
06/13/2025
Informed Delivery Mail.dat Mailer Guide
This is a mailer guide for creating campaigns via PostalOne! through Mail.dat eDoc submission.
05/06/2025
eVS to USPS Ship Migration Tech Sheet
The Postal Service is retiring the electronic verification system (eVS). eVS customers must migrate to USPS Ship or USPS APIs by February 2025. This includes customers using Premium Forwarding Services Commercial (PFSC) and Click N Ship BusinessPro (CNBPro). This document outlines the differences between the two platforms and steps to migrate from eVS to USPS Ship.
05/06/2025
03/07/2025
Secure Destruction Technical Guide
A technical reference for implementing the Secure Destruction process
02/21/2025
ACS™ Electronic Product Fulfillment (EPF) Fulfillment File Access
Learn the different methods of accessing your ACS™ files from EPF.
01/23/2025