---
title: >-
  New owner_type field for metafield declarations in Checkout and Customer
  Account UI extensions, required in 2027-01 - Shopify developer changelog
description: >-
  Shopify’s developer changelog documents all changes to Shopify’s platform.
  Find the latest news and learn about new platform opportunities.
source_url:
  html: >-
    https://shopify.dev/changelog/posts/metafield-owner-types-required-for-checkout-and-customer-account-ui-extensions
  md: >-
    https://shopify.dev/changelog/posts/metafield-owner-types-required-for-checkout-and-customer-account-ui-extensions.md
metadata:
  effectiveApiVersion: 2026-10
  affectedApi:
    - displayName: Checkout UI
      handle: checkout-ui-api
    - displayName: Customer Accounts
      handle: customer-accounts
  primaryTag:
    displayName: API
    handle: api
  secondaryTag:
    displayName: Update
    handle: update
  indicatesActionRequired: true
  createdAt: '2026-09-21T16:19:49-04:00'
  postedAt: '2026-10-08T13:00:00-04:00'
  updatedAt: '2026-10-09T09:03:09-04:00'
  effectiveAt: '2026-09-28T12:00:00-04:00'
---

October 8, 2026

# New `owner_type` field for metafield declarations in Checkout and Customer Account UI extensions, required in 2027-01

DateOctober 8, 2026

Version[2026-10](https://shopify.dev/changelog?api_version=2026-10)

FlagsUpdate[Action required](https://shopify.dev/changelog?action_required=true)

SurfacesAPI

Affected APIs[Checkout UI](https://shopify.dev/changelog?api_type=checkout-ui-api)[Customer Accounts](https://shopify.dev/changelog?api_type=customer-accounts)

Starting with API version `2026-10`, Checkout and Customer Account UI extensions can specify an `owner_type` for each metafield declaration in `shopify.extension.toml`. Starting with API version `2027-01`, `owner_type` is required for every metafield declaration, and deployments without it will be blocked.

## What changed

Metafield declarations in `[[extensions.metafields]]` and `[[extensions.targeting.metafields]]` accept a new `owner_type` property. `owner_type` names the resource that owns the metafield, such as `PRODUCT` or `CUSTOMER`.

Shopify uses `owner_type` to fetch only the metafields from the resource types your extension needs, which improves extension performance. On API version `2027-01` and later, every metafield declaration must include `owner_type`.

## Who's affected

Checkout and Customer Account UI extensions that declare metafields in `shopify.extension.toml` and use API version `2027-01` or later are affected.

Extensions that don't declare metafields in `shopify.extension.toml` are unaffected.

## What to do

On API version `2027-01` or later, deployments will be blocked if any metafield declaration is missing an `owner_type`. Add `owner_type` to each metafield declaration before you upgrade. You can add it now on `2026-10`.

To migrate:

1. Open your extension's `shopify.extension.toml` file and add the appropriate `owner_type` value for each metafield declaration.
2. If your extension needs the same `namespace` and `key` from multiple resource types, create a separate declaration for each `owner_type`.
3. Redeploy the extension and confirm that the deployment completes without validation errors related to metafield declarations.

## Related docs

* [Configure metafields for Checkout UI extensions](https://shopify.dev/docs/api/checkout-ui-extensions/2026-10#configuration)
* [Configure metafields for Customer Account UI extensions](https://shopify.dev/docs/api/customer-account-ui-extensions/2026-10#configuration)