United States Postal Service (USPS) provides trusted mail and shipping services across the country. USPS enables businesses to validate, standardize, and enhance address data with accurate postal information. By ensuring deliverability and reducing errors, USPS helps organizations improve customer satisfaction, optimize shipping processes, and streamline operations.
Where You’ll Use USPS Address Validation
USPS address validation is available in two key areas of EvolutionX:
Checkout
During checkout, customers can use USPS to look up and standardize their address. This optional step helps ensure accurate shipping details and reduces delivery errors.
Address List View
In the address list view, customers can use USPS to look up new addresses when adding them. This optional step helps ensure the saved addresses are accurate and consistent.
Installation
Get Credentials from USPS Developer Portal
Follow the instructions from the USPS APIs Onboarding Guide:
All customers can skip Step 2: Add Payment Account, which is only required to generate labels using USPS, and this feature is not supported by EvolutionX.
Customers who already have a USPS Business Account can go directly to Step 3: Login to USPS Developer Account.
In Step 4: Create an App, the “Callback URL” is not required and can be left empty.
⚠️ Important: By default, the USPS product allows 60 API calls per hour per API. To request higher limits review this page in USPS.
Setting Up OAuth 2.0 Credentials
Enter the following values in the OAuth 2.0 By EvolutionX Integration app to connect your USPS account.
OAuth Endpoint: https://apis.usps.com/oauth2/v3/token
OAuth Token Life: 6 hours
OAuth Grant Type: Client Credentials
OAuth Client ID: Credentials from USPS Developer Portal (see here)
OAuth Client Secret: Credentials from USPS Developer Portal (see here)
OAuth Resource Body Key: resource
OAuth Resource: https://www.usps.com/
OAuth Scope: addresses
JSONata Token Response: access_token
Install From The App Store
Enable the USPS V2 App from the App Store under the Address category.
Go to EvolutionX Admin → App Store → USPS V2 Integration.
Authentication Type: OAuth 2.0 using EvoX
Error Messages
"System error. Address cannot be verified." — This can indicate that the USPS API limit was exceeded or the system is down. Check the event logs for more information.
"Address cannot be verified." — This error means the USPS system is working but could not find a match for the address entered. Please check your inputs or enter your address using the manual option.