USPS Shipping

This optional extension integrates with the United States Postal Service (USPS) API, allowing real time calculation of shipping costs for the USPS shipping options specified in your settings. The extension integrates seamlessly with native shipping options while providing even more choices.

USPS Shipping is a paid extension, available on the ExpressionEngine Add-on store.

Installation

1. Ensure you are running the latest version of Expresso Store
2. Upload the extension to system/user/addons/store_usps on your server
3. In the ExpressionEngine control panel, visit Add-Ons > Extensions, and click Install next to Store USPS Shipping
4. Click Settings next to the extension to configure it

USPS Setup

To use the USPS shipping extension, you will need to set up a USPS account. You can do this by visiting the USPS developer website and creating an account. Once you have created an account, you will need to set up a USPS API key. You can do this by visiting the USPS developer website and creating an account.

Once you have created an account, you will need to set up a USPS API app and add the Public Access for the newly named app. When completed it will look like this:

Configuration

The USPS Shipping extension will automatically add shipping method options to your checkout. To display the shipping options inside your checkout tag, use the {field:shipping_method} variable. For more information, see the Checkout Tag Shipping Methods.

Client ID

Your USPS Client ID.

Client Secret

Your USPS Client Secret.

Source ZIP

The ZIP where you will be sending items from.

Service

Which service options you would like to provide to your customers.

First Class Mail Type

The first class mail type only applies if you set Service to First Class.

Container

The container type you will be shipping orders in. If unsure, or you will be providing your own packaging, select “Unknown”.

Size

Set this to Large if any of your package dimensions will exceed 12”.

Machinable

Whether the package is machinable.

Version History

v2.0.0

June, 2025

• Updated to use the new USPS
• The shipping_city is once again required to calculate shipping
• Updated for use of Store version 6

v1.0.2

February 19, 2014

• Fixed shipping cost when all products in the cart have free shipping
• shipping_city is no longer required to calculate shipping

v1.0.1

October 26, 2013

• Restructured zip file layout to mirror EE direcotries
• Minor language string changes

v1.0.0

September 9, 2013

• Initial version