If you're registered with USPS to receive live shipping rates on your store's checkout page, these service codes will be pre-programmed into your store's shipping table by default. However, we recommend you double-check your settings against our list below to avoid any unnecessary shipping snafus.
USPS updated their Live Rate API on January 25th, 2026.
In order to avoid any interruption you are required to re-connect your account within your Volusion admin dashboard. You'll need to ensure you have a Business account with USPS.
The onboarding process is much smoother if you are logged into your USPS account first.
To get started follow the steps below:
1. Go to cop.usps.com and log into your account.
2. Ensure you have enabled the shipping rate API and that your account is fully set up. The page will show a green check mark that says
‘Your account was transitioned from EVS to SHIP/USPS APIs’
3. In the same browser, open a new tab and Login to your Volusion Admin Dashboard and go to Settings > Shipping
4. Go to the Live Rate Section and select USPS in the drop down and then click on 'connect'.
5. This should take you to an authorization screen, check the box to agree to the terms and click submit.
6. You should be redirected to your admin dashboard with a message stating you have successfully onboarded.
There should not be any other necessary steps until we get closer to the official transition, at which time we will send out additional notices and information.
Not yet registered with USPS to offer live rate shipping in your Volusion store? Check out our main Shipping article, particularly the Shipping Methods and Live Rate Shipping Methods sections.
USPS Service Codes
In the list below, the text in bold corresponds to each shipping method's default name, while the text to the right corresponds to that method's service code.
Domestic Codes
USPS Library: Library Mail Machinable Single-piece
USPS Media Mail: Media Mail Machinable Single-piece
USPS BPM (Bound Printed Matter): Bound Printed Matter Machinable Presorted
USPS Ground Advantage: USPS Ground Advantage
USPS First-Class Mail Large Envelope: First-Class Mail Large Envelope
USPS First-Class Mail Letter: First-Class Mail Letter
USPS Priority Mail Flat Rate Envelope: Priority Mail Flat Rate Envelope
USPS Priority Mail: Priority Mail
USPS Priority Mail Padded Flat Rate Envelope: Priority Mail Padded Flat Rate Envelope
USPS Priority Mail Legal Flat Rate Envelope: Priority Mail Legal Flat Rate Envelope
USPS Priority Mail Small Flat Rate Box: Priority Mail Small Flat Rate Box
USPS Priority Mail Medium Flat Rate Box: Priority Mail Medium Flat Rate Box
USPS Priority Mail Large Flat Rate Box: Priority Mail Large Flat Rate Box
USPS Priority Mail Military Large Flat Rate Box: Priority Mail Large Flat Rate APO/FPO/DPO
USPS Priority Mail Express: Priority Mail Express
USPS Priority Mail Express Flat Rate Envelope: Priority Mail Express Flat Rate Envelope
USPS Priority Mail Express Padded Flat Rate Envelope: Priority Mail Express Padded Flat Rate Envelope
USPS Priority Mail Express Legal Flat Rate Envelope: Priority Mail Express Legal Flat Rate Envelope
USPS First-Class Mail Stamped Letter: First-Class Mail Stamped Letter
USPS First-Class Mail Metered Letter: First-Class Mail Metered Letter
First-Class Mail Postcards: First-Class Mail Postcards
First-Class Mail Large Postcards: First-Class Mail Large Postcards
International Codes
USPS First-Class Mail International Letter: First-Class Mail International Letter
USPS First-Class Mail International Large Envelope: First-Class Mail International Large Envelope
USPS First-Class Package International Service: First-Class Package International Service Machinable ISC Single-piece
USPS Priority Mail International: Priority Mail International Machinable ISC Single-piece
USPS Priority Mail International Flat Rate Envelope: Priority Mail International ISC Flat Rate Envelope
USPS Priority Mail International Small Flat Rate Box: Priority Mail International Machinable ISC Small Flat Rate Box
USPS Priority Mail International Padded Flat Rate Envelope: Priority Mail International Machinable ISC Padded Flat Rate Envelope
USPS Priority Mail International Medium Flat Rate Box: Priority Mail International Machinable ISC Medium Flat Rate Box
USPS Priority Mail International Legal Flat Rate Envelope: Priority Mail International ISC Legal Flat Rate Envelope
USPS Priority Mail International Large Flat Rate Box: Priority Mail International Machinable ISC Large Flat Rate Box
USPS Priority Mail Express International: Priority Mail Express International Machinable ISC Single-piece
USPS Priority Mail Express International Flat Rate Envelope: Priority Mail Express International ISC Flat Rate Envelope
USPS Priority Mail Express International Padded Flat Rate Envelope: Priority Mail Express International ISC Padded Flat Rate Envelope
USPS Priority Mail Express International Legal Flat Rate Envelope: Priority Mail Express International ISC Legal Flat Rate Envelope
To note:
*If you need to adjust the service codes for your shipping methods, reach out to Support for assistance.
⚠️ Don’t Delete.
Deleting a record from your store’s Shipping Table is permanent. We recommend de-activating any shipping methods you don’t want to offer at checkout. Simply deselect the Active check box within each method or on the main Shipping page and click save.