About the EasyPost shipping calculation in coreFORCE

coreFORCE integrates with EasyPost to provide real-time shipping rate calculations from multiple carriers. When enabled, EasyPost returns the lowest available rate based on product weight, store location, and the customer’s shipping address.

This article explains when and how EasyPost is used, what exclusions apply, and how the final shipping charge is calculated.

Prerequisites

Signature requirement

If applicable, coreFORCE checks whether a product requires a signature upon delivery. Some carriers may apply an additional charge for shipments that require a signature. To enable a product signature requirement, the following settings must be configured.

Setup of the RETAIL_STORE_REQUIRE_SIGNATURE preference

The RETAIL_STORE_REQUIRE_SIGNATURE preference is configured by the Coreware Support Team for coreFORCE Advanced users. Contact the Coreware Support Team to verify that this preference is set up for you.

Specifying the FFL Required product tag

For coreFORCE Basic users:

1. On the sidebar, select Products > Products.
2. On the Products Maintenance page, select a product in the table.
3. Select the Categories tab.
4. In the Tags section, click the Add button.
5. In the Product Tag column, select FFL Required.
6. Click Save.

For coreFORCE Advanced users:

1. On the sidebar, select Products > Products > Products.
2. On the Products Maintenance page, select a product in the table.
3. Select the Options tab.
4. In the Tags section, click the Add button.
5. In the Product Tag column, select FFL Required.
6. Click Save.

Verifying your connection to EasyPost

1. For coreFORCE Basic users, select Setup > Site Defaults. For coreFORCE Advanced users, select Orders > Setup.
2. On the Site Defaults or Order Settings page, select the EasyPost tab.
3. In the EasyPost API Key field, enter the API key you received from EasyPost.
4. Click Test EasyPost API.

Requiring signatures by default using department codes

1. For coreFORCE Basic users, select Setup > Site Defaults.  For coreFORCE Advanced users, select Orders > Setup. 
2. On the Site Defaults or Order Settings page, select the EasyPost tab.
3. In the Signature required for these departments (comma separated list of department codes) field, specify the department of the product. To know the department of the product, view its Categories Summary section on the Categories tab of the Products Maintenance page.
4. Click Save.

Product availability

EasyPost is used only when one of the following conditions is met:

• The product is available at a local store location.
• The product is available from a distributor location configured as a local source.

Configuring a distributor as a local source

1. On the sidebar, select Orders > Setup. 
2. On the Orders Settings page, select the Settings tab.
3. In the Product distributors as local for shipping field, enter the coreFORCE ID of the product distributor. For details about the ID, contact the Coreware Support Team.
4. Click Save.

Using EasyPost for shipping calculation

1. For coreFORCE Basic users, select Setup > Shipping Charges. For coreFORCE Advanced users, select Orders > Settings > Shipping Charges.
2. On the Shipping Charges page, select a charge in the table.
3. Select the Use EasyPost to calculate shipping checkbox.
4. Enter the following information:

• • Shipping Service Flat Rate (required): Flat rate added to each box during shipping service calculations
  • Shipping Service Percentage: Percentage added to each box during shipping service calculations
  • Shipping Service Maximum Weight: Maximum weight allowed per box for shipping service calculations

5. Click Save.

EasyPost shipping calculation workflow

1. Dimensions and weights

coreFORCE collects the product’s physical characteristics, including height, width, length, weight, and volume. If the product weighs less than 0.25 lbs or has no defined weight, coreFORCE bypasses EasyPost.

2. Package count calculation

When a value specified in the Shipping Service Maximum Weight field:

• coreFORCE divides the total order weight by the maximum weight allowed per package.
• The result is rounded up to determine the total number of packages.

If no maximum weight is set, coreFORCE defaults to 1 package. This may cause EasyPost to fail if the package exceeds the carrier’s weight limit.

3. Shipping carrier exclusions

Some carriers may be excluded from EasyPost calculations from restrictions based on product, category, or department. Excluded shipping carriers are configured through the following:

• Prohibited shipping carrier by product categories: Products > Taxonomy > Categories > [Select a category in the table] > Shipping tab > [Select a checkbox in the Prohibited Shipping Carriers section].

• Prohibited shipping carrier by product: Products > Products > [Select a product in the table] > Shipping tab > [Select a checkbox in the Prohibited Shipping Carriers section].

For details, learn more about shipping charge exclusions in coreFORCE.

Final shipping rate adjustments

After EasyPost returns a valid shipping rate, coreFORCE applies final adjustment based on the following fields (if configured):

• Shipping Service Flat Rate: Flat rate added to each box during shipping service calculations
• Shipping Service Percentage: Percentage added to each box during shipping service calculations
• Minimum Shipping Charge: This amount will be used as shipping charge if the calculated charge is less than this.

If the final shipping rate is greater than zero, it is used for that method and no further calculations are performed.

Fallback behavior

If EasyPost doesn’t return a valid rate (for example, due to excessive weight or missing data), coreFORCE uses the default shipping charges configured for the selected method.

This ensures that customers still see valid shipping options at checkout, even when EasyPost is temporarily unavailable or cannot process the order.

Summary

coreFORCE integrates with EasyPost to deliver real-time shipping rates based on product availability, physical dimensions, and store or distributor location. EasyPost is used only when conditions such as minimum product weight and inventory rules are met. Users can fine-tune the calculation by setting flat rates, percentage-based fees, and maximum box weight limits.

If EasyPost does not return a valid rate because of carrier restrictions, data issues, or product settings, coreFORCE uses the default shipping charges as a fallback. This ensures consistent and dependable shipping rate display during checkout.

Updated on: 08/15/2025