How do carrier aliases map a channel’s shipping methods to carrier services, and what happens when one is missing?

A carrier mapping connects an integration’s shipping method or carrier codes with an Endless carrier service. Add a custom mapping on the integration’s Data mapping tab, under Shipping Carriers and Methods. Use the external values exactly as the integration expects, including capitalization and leading zeros. The Endless service can be Rate Shop or a specific service.

On the updated integration page, built-in system mappings appear alongside your custom mappings. Built-in rows remain visible when a custom mapping overrides them. You can edit your custom mappings and choose the preferred outgoing mapping where supported. The page explains whether mappings apply to incoming orders, outgoing work, or warehouse shipments, and displays outgoing fallback defaults separately.

Incoming order mappings resolve the customer’s requested shipping method. A new fulfillment copies the order’s selected carrier service, or tries mapping its shipping method. Existing fulfillments keep their own selection when you change a mapping or the order’s request.

Outgoing mappings translate the selected service into the codes the receiving integration expects. Different integrations use different fields and defaults, so follow the guidance shown for that integration. Shopify shipment reporting uses the shipment’s carrier name.

If a fulfillment has no carrier service, use Resolve carrier service to select one. Where offered, the checkbox to map the method for future orders also saves a custom mapping. Check the source integration and exact incoming text if a mapping does not apply.

Rate Shop asks the warehouse to choose the carrier and rate. Configure carrier exclusions in the warehouse system. Contact Endless support for help interpreting an integration’s carrier values.