• Overview
• Creating Your FedEx Freight Developer Account
• Adding Your FedEx Freight Shipping Account
• Getting Your FedEx Freight API Credentials
• Connecting FedEx Freight to Cart.com
• Configuring FedEx LTL Freight Options
• Testing Your FedEx Freight Integration
• Error Messages and Troubleshooting

Overview

Your store can automatically calculate Less-Than-Truckload (LTL) freight shipping rates using FedEx Freight. To set up this integration, you will need an active FedEx Freight shipping account and API credentials obtained through the FedEx Freight Developer Portal. 

FedEx Freight has transitioned to a separate developer platform for its LTL freight APIs. The newer FedEx Freight APIs use a different authentication service and credentials from the standard FedEx parcel shipping APIs.

Important: If your store currently uses FedEx for standard parcel shipping, your existing FedEx provider settings should remain unchanged. FedEx Freight requires its own API configuration.

For standard FedEx parcel shipping, please refer to our How to Set Your FedEx Shipping Provider article.

Creating Your FedEx Freight Developer Account

To begin, create an account or sign in through the FedEx Freight Developer Portal.

• Navigate to the FedEx Freight Developer Portal.
• Click Create Account to register, or Log In if you already have an account

• Complete any required account registration and verification steps.
• Once signed in, navigate to My Integrations.

If you have not yet created or joined an organization, the portal may prompt you to do so.

• Create an organization using your company information, or join an existing organization if your business already has one.
• Complete the required organization details.
• Confirm that your developer account has permission to manage projects and shipping accounts.

Note: If your company already has a FedEx Freight developer organization, you may need an invitation or assistance from the existing organization administrator.

FedEx Freight Shipping Account

You will need an active FedEx Freight shipping account to use the FedExLTL shipping provider in Cart.com.

Your FedEx Freight account number will be entered separately when configuring the shipping provider in your Cart.com Storefront administration panel.

Note: Depending on your existing FedEx Freight developer account and integration configuration, additional account verification may be required before production API access is available.

If your shipping account is not associated with your integration, or you cannot request production credentials, contact your FedEx Freight Account Manager or FedEx Freight support for assistance.

Important: The billing information must match the information associated with your FedEx Freight shipping account. Incorrect account information may prevent successful verification.

Once your shipping account has been successfully linked, you can proceed with creating an API project.

Getting Your FedEx Freight API Credentials

The FedEx Freight Developer Portal provides API credentials used to authenticate requests to FedEx Freight services.

You will need a Client ID (also referred to as an API Key) and a Client Secret (also referred to as a Secret Key).

Creating an API Project

• Log in to the FedEx Freight Developer Portal.
• Navigate to My Integrations.

• Select the option to create a new integration.
• When asked why you need API access, select the option for Shipper interacting with Freight APIs, then click continue. 
• Enter a descriptive project name, such as Cart.com Storefront Freight.
• Check the box for Rates under APIs to include.
• Select the Countries you plan to ship from. 
• Read/Accept the Terms and Conditions and click Continue. You'll be brought to a page with test credentials. Do not use sandbox or test credentials when configuring the live shipping provider on your storefront. 
• Scroll down and click "Back to My Integrations" to request production access for the new integration. 

Generating Production API Credentials

After creating your project, locate the production credentials that will be used with your live Cart.com store.

• Return to My Integrations and select your newly created Integration.
• Open the Details section below the integration and select Request production access. 

• Copy your Client ID (API Key) and Client Secret (Secret Key).

  Important: Your Client ID and Client Secret are only shown once. Copy these credentials directly into your storefront's FedEx Freight shipping provider settings, or store them somewhere secure (a secrets manager, password vault, etc.). If you lose them, you can rotate to new ones later from integration settings.

Customer Identifier (x-client-id): In addition to your Client ID and Client Secret, FedEx Freight assigns a unique Customer Identifier to your organization. This value is provided separately by email after registering through the FedEx Freight Developer Portal.

Look for an email from the FedEx Freight Developer Portal Team containing your assigned Customer Identifier. You will need this value when configuring the FedExLTL shipping provider in Cart.com.

Important: The Customer Identifier is used in the x-client-id HTTP request header for both test and production environments. Requests without the assigned identifier may be rejected with a 403 Access Denied error.

If you have not received your Customer Identifier, contact your FedEx Freight Account Manager or the FedEx Freight Help Desk at 1-800-435-7949.

Connecting FedEx Freight to Cart.com

Once you have obtained your production API credentials, you can configure the FedEx Freight shipping provider in your Cart.com store.

• Log in to your Cart.com Storefront administration panel.
• Navigate to Settings > Shipping > Shipping Providers.
• Locate FedExLTL and click the edit icon.
• Enter your FedEx Freight Account Number, Client ID, Client Secret, and the Customer Identifier (x-client-id). 
• Set the shipping provider to Active.
• Click Save.

Important: The new FedEx Freight credentials are separate from your standard FedEx parcel shipping credentials. Do not overwrite the credentials configured for your existing FedEx parcel provider.

After saving, review the shipping services available for the FedEx Freight provider at the bottom of Settings > Shipping > Shipping Providers and enable the services you want to offer at checkout.

For additional information, see our Shipping Provider Live Rate Setup article.

Configuring FedEx LTL Freight Options

In addition to configuring your FedExLTL shipping provider credentials, you will need to review the additional freight settings for your store.

• Navigate to Settings > Shipping > Shipping Provider Settings.
• Scroll down to the FedEx LTL Freight Options section.
• Configure the following settings:
  • Account Number: Enter your FedEx Freight shipping account number.
  • Billing Address: Enter the billing street address associated with your FedEx Freight account.
  • Billing City, State, and Zip: Enter the billing location associated with your FedEx Freight account.
  • Freight Class: Select the appropriate freight classification for your shipments. Available classes range from 050 through 500, including intermediate classifications such as 077.5 and 092.5.
  • Rate Type: Select the type of freight rates returned by the FedEx Freight integration:
    • Retail: Returns both account-specific (discounted) rates and standard published rates.
    • Account: Returns account-specific rates in the currency specified.
• Click Save to apply your changes.

Note: The freight class selected should match the classification applicable to your shipments. Incorrect freight classifications may affect the accuracy of the returned shipping rates.

Testing Your FedEx Freight Integration

Once your credentials have been saved, test the provider to verify that your store can communicate with FedEx Freight.

• Navigate to Storefront > Settings > Shipping > Shipping Providers.
• Edit the FedExLTL provider.
• Scroll to the bottom and click Test Connection
• Review the response for any authentication or configuration errors.

After successfully testing the provider connection, we recommend testing freight rates using an example shipment that qualifies for LTL service.

Verify the following shipment details:

• Shipping origin ZIP code and address.
• Shipping destination ZIP code and address.
• Shipment weight and dimensions.
• Freight classification and other required LTL details.
• Available freight service types.
• Applicable account-specific rates.

Note: Successfully authenticating with FedEx Freight does not guarantee that a freight rate will be available for every shipment. Rate availability depends on shipment details, account configuration, and available services.

Error Messages and Troubleshooting

Invalid API Credentials or Authentication Errors

If you receive an authentication error when saving or testing your FedEx Freight provider, verify the following:

• Your credentials were generated through developer.fedexfreight.com, rather than the standard FedEx Developer Portal.
• You entered the correct production Client ID and Client Secret.
• Your Client Secret has not been revoked, rotated, or regenerated.
• Your API project is authorized to access the necessary FedEx Freight rating APIs.
• Your FedEx Freight shipping account is associated with the correct developer organization and integration.

403 Access Denied

If you receive a 403 Access Denied error when testing your FedEx Freight connection, verify that the Customer Identifier (x-client-id) field contains the unique value assigned to your organization by FedEx Freight.

FedEx Freight requires this identifier in API request headers for traffic identification, monitoring, and troubleshooting. Missing or incorrect values may cause requests to be rejected.

If you do not have your assigned Customer Identifier, contact your FedEx Freight Account Manager or the FedEx Freight Help Desk at 1-800-435-7949.

No Freight Rates Returned

If your credentials are accepted but freight rates are not displayed at checkout, verify the following:

• The FedEx Freight shipping provider is active.
• The appropriate freight shipping services are enabled.
• Your product weights and required freight information are accurate.
• The shipment qualifies for the available FedEx Freight services.
• Your FedEx Freight account is authorized for the requested service.

For additional troubleshooting, see our Troubleshooting No Shipping Options article.

For assistance with your FedEx Freight developer account, API access, or shipping account authorization, please visit the FedEx Freight Developer Portal.