Metafields now require a definition to be accessed through the Customer Account API
Shopify developer change
MerchantDiff detected this entry in Shopify's official developer changelog on June 16, 2026.
This Shopify update is categorized as Action Required, Platform, Update.
What changed
Starting today, metafields stored on the app resource must have a metafield definition and customer accounts permissions to be accessible through the Customer Account API. Going forward, when calling the Customer Accounts API, app metafields without a definition will no longer return a value. If your app has functionality which depends on these fields, update those metafields to use definitions with the Customer Account API permission to avoid disruption.
Who is affected
Developers building customer account experiences or extensions should review this change.
What action may be needed
You must ensure that every metafield your app uses for customer account UI extensions, a Hydrogen or a Headless store, has a definition. Run the metafieldDefinitionCreate for every store that installs your app to ensure the metafields are correctly defined. For app-owned metafields, configure declarative metafields in your app’s TOML file. Configure the access settings on your definition to allow customer accounts API access.
Use the official Shopify entry below as the source of truth for technical implementation details, affected APIs, migration instructions and deadlines.
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