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New USPS Version 3 Integration for v5.5

ProductCart now offers USPS newest "Version 3" shipping integration. This will ensure future compatibility.

The United States Postal Service (USPS) has announced the retirement of its legacy Web Tools API platform, which includes various online shipping integrations. The official sunset date for these services is January 25, 2026. It is best to read line up all the necessary IDs and keys before installing v5.5 to ensure no break in service after upgrading.

IMPORTANT NOTE:  Part of the onboarding service is receiving a Enterprise Payment System (EPS) number, which can take 2 to 3 days to verify. Given the nature of this, give yourself plenty of time to set this up before upgrading your version to v5.5. 

Existing USPS customers need to do the onboarding to connect their USPS account with and signup for the Business Customer Gateway through USPS Customer Onboarding Portal (COP).  This process will be able to get/create/review all of the required numbers for the new USPS shipping integration. These numbers include your EPS, CRID, MID and Manifesting MID information, which you'll need to both return rates and create shipping labels. You may also use Endicia to create shipping labels too for USPS.

To begin the onboarding, or, once you have your API Keys, EPS, CRID, MID and Manifest MID you can connect your account through your ProductCart control panel main menu under SHIPPING > ADD & VIEW SHIPPING SERVICES, then open the United States Postal Service (USPS) tab and click the link to add the service.

NOTE: You Only need your Keys and EPS for returning rates. If you don't use Endicia for shipping labels, then you will need to include your CRID,  MID, and Manifest MID to create labels through ProductCart.


Screenshots below of what the new USPS interface looks like in ProductCart version 5.5.