--- title: >- Tax summary webhook created_at field now returns UTC timezone - 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/tax-summary-webhook-created-at-field-now-returns-utc-timezone md: >- https://shopify.dev/changelog/tax-summary-webhook-created-at-field-now-returns-utc-timezone.md metadata: effectiveApiVersion: 2026-01 affectedApi: - displayName: Webhook handle: webhook - displayName: Admin GraphQL API handle: admin-graphql primaryTag: displayName: API handle: api secondaryTag: displayName: Breaking API Change handle: breaking-api-change indicatesActionRequired: true createdAt: '2025-11-19T12:20:10-05:00' postedAt: '2025-11-20T12:00:00-05:00' updatedAt: '2025-11-20T12:13:38-05:00' effectiveAt: '2025-11-20T12:00:00-05:00' --- November 20, 2025 Tags: * Action Required * Webhook * Admin GraphQL API * 2026-01 # Tax summary webhook `created_at` field now returns UTC timezone ## What's new The `created_at` field from `tax_summaries/create` webhook for tax partners will now return timestamps in UTC format with the `Z` suffix, including millisecond precision. ## Action required Update your parsing logic to handle the new format. The following are examples of the format prior to and after the change: Versions prior to `2026-01`: ```json { "id": 14, "shop_id": 1, "order_id": 7, "created_at": "2025-11-19T08:16:53-05:00", "summary": { ... } } ``` Versions `2026-01` and higher. ```json { "id": 14, "shop_id": 1, "order_id": 7, "created_at": "2025-11-19T13:16:53.784Z", "summary": { ... } } ```