The following instructions apply to setting up integration credentials for the USPS REST API integration. The USPS REST API integration is native in Znode versions 9.9 and later. REST API access is used for shipping rate estimates and for address validation. Access to shipping rate APIs is free but as of July 12, 2026, USPS requires a paid subscription to access the Enhanced Addresses API. If you plan on using Address Validation in Znode, there are additional steps required to get access in Step 5. 

Step 1: Log In or Create USPS Business Account 

Use the USPS Customer Onboarding Portal (COP), sign into your USPS Business Account, or create a new USPS Business Account. The COP will ensure that your USPS Business Account is configured for the USPS APIs. If you do not have an account, click the “Create New Account” link on the portal and follow the steps. Once completed, continue to Step 2. 

Step 2: Create a Developer Portal App 

After you login to the USPS Business Account, if you do not already have a Znode App created, create a USPS App by navigating to the My Apps page.  

Use the following values when adding the App: 

• Enter a value for the “App name”. This value names the software that is connecting to the USPS APIs. 

• Leave the “Callback URL” blank. 

• Review the Terms and Conditions and Privacy Policy documentation. The ability to continue creating the app is contingent on your agreement. If you agree, check the box. 

• Add a “Description” for the app, if desired. 

After the app has been created, you will be returned to the App listing screen and the newly created App should appear in the list as an “Approved” App. 

Step 3: Retrieve your Consumer Key and Secret 

Within COP, select your App and retrieve your Consumer Key and Consumer Secret from the Credentials section. These credentials are required for generating the OAuth Token. 

Step 4: Configure Znode USPS Shipping  

The USPS environment URL is configured in the web.config file. The production URL value should already be configured, however, please verify the value. 

web.config file Snippet 

<!--USPS Rest Base URL -->
<add key=”USPSRestBaseUrl” value=”https://apis.usps.com” /> 

This configuration is needed for each store that uses USPS shipping. In the Znode Admin, browse to the “Stores & Reps” > “Stores” > “Shipping Origin” screen and scroll to the “USPS” section. 

• USPS Consumer Key. The value associated with the “Consumer Key” heading of the USPS App in the Developer Portal.  
• USPS Consumer Secret. The value associated with the “Consumer Secret” heading of the USPS App in the Developer Portal. 

Step 5: Required Steps for Address Validation 

USPS launched an upgraded Enhanced Addresses API on July 12, 2026, at which time a paid license is required to access. 

1. Follow the steps to add an Addresses API License 
   1. USPS Business Portal → My Account > API Licenses > Add License
2. Set up payment(if not already in place) 
   1. Create an Enterprise Payment Account (EPA) that can be linked to the license.
3. Sign license agreement 
   1. USPS will send a DocuSign agreement for completion
4. Link your API credentials to the license(after USPS countersignature) 
   1. USPS Business Portal → API Licenses > Set Up Address on license