lastIncompleteCheckout field and Checkout type removed

As of Customer Account API version 2026-10, the deprecated Customer.lastIncompleteCheckout field is removed.

This also removes the now-unreachable Customer Account API Checkout type subtree, including:

• Checkout
• Checkout.appliedGiftCards
• AppliedGiftCard
• AvailableShippingRates
• CheckoutLineItem
• CheckoutLineItemConnection
• CheckoutLineItemEdge
• ShippingRate

The Customer.lastIncompleteCheckout field was previously deprecated and returned null. This change removes stale Checkout Classic schema from the Customer Account API.

Action required

If your app queries Customer.lastIncompleteCheckout or any nested fields on the returned Checkout object, update your queries before upgrading to API version 2026-10.

Remove selections such as:

customer {
  lastIncompleteCheckout {
    id
    appliedGiftCards {
      id
    }
  }
}

There is no replacement field in the Customer Account API.

If you need active cart or checkout state for a buyer storefront experience, use Storefront API cart flows instead. If you need completed customer purchase history, use the Customer Account API Customer.orders field.