New SubscriptionContractCalculation API for subscription management
Shopify developer change
MerchantDiff detected this entry in Shopify's official developer changelog on October 01, 2026.
This Shopify update is categorized as Action Required, API, New, GraphQL Admin API, Functions, 2026-10.
What changed
A new SubscriptionContractCalculation API is now available to manage subscriptions. This new API runs subscription contract edits through Shopify's checkout engine, enabling new capabilities: Shopify Functions, including cart transforms and delivery customizations are supported during contract calculations Contract edits align with what the subscriber sees during billing Get a preview of the full calculated contract (totals, delivery options, and warnings) before persisting any changes Developers using the SubscriptionDraft API should migrate to SubscriptionContractCalculation API. The SubscriptionDraft API will remain available but will not support the new capabilities. See the migration guide and updated subscriptions build guides and API docs.
Who is affected
Apps using the affected Shopify GraphQL API surface should review this change.
What action may be needed
Review the official Shopify entry and test the affected integration. Apply any required code or configuration changes before deploying.
Use the official Shopify entry below as the source of truth for technical implementation details, affected APIs, migration instructions and deadlines.
Want the actionable version?
MerchantDiff monitors Shopify API changes, deprecations, deadlines and ecosystem updates, then turns them into developer-focused release intelligence: what changed, who is affected and what action may be needed.
Get MerchantDiff →