Shopify's Customer Account API version 2026-10 removes the deprecated `Customer.lastIncompleteCheckout` field and the entire `Checkout` type subtree. The field previously returned null, so this is a cleanup of stale Checkout Classic schema. Developers must update any queries that reference `lastIncompleteCheckout` or nested `Checkout` fields before upgrading. There is no direct replacement in the Customer Account API — for active cart/checkout state use Storefront API cart flows, and for purchase history use `Customer.orders`.
Table of contents
Action required156 Impressions