Shipping

Shipping availability is resolved from the cart’s address and commerce context. Thor evaluates zones, shipping method channels and predicates, and eligible rates before returning the methods a buyer can select.

Shipping zones

A shipping zone is a named group of country locations. Add every country a method is meant to serve, and keep overlapping zones intentional. The cart needs a shipping address with a country before address-dependent shipping options can resolve.

Shipping methods

A shipping method has a name, SKU, optional description and metadata, associated zones and channels, an optional cart predicate, and one or more rates.

The method predicate controls whether the method is eligible for the cart. Use it for rules such as customer-group, order-value, or cart-content restrictions. See Cart predicate reference.

Rates

A rate can provide either a fixed MoneyInput price or a rateOfTotal calculation. It can have its own predicate and tax behavior. This allows one method to expose different prices for different cart conditions.

Keep rate order deterministic when multiple rates can match, and make predicates mutually clear. Test boundary amounts and missing address or customer fields explicitly.

Custom checkout flow

  1. Create or update the cart with a complete shipping address.
  2. Request availableShippingMethods from the latest cart.
  3. Show only the returned methods and rates.
  4. Add the selected shipping line with cartShippingLineAdd, or set custom shipping lines when your integration owns the rate.
  5. Render the newly returned totals and tax values.

Do not cache availability independently of the cart. Line items, discounts, address, customer identity, and market context can change the result.

Hosted checkout uses the same configured commerce rules through the cart’s checkoutUrl. See Cart and checkout.

External shipping methods

The Admin API also exposes external shipping method registrations. Use them when method resolution is supplied by an integration, and monitor that integration as checkout-critical infrastructure.

API reference