Desk research · Shopify platform

Which Shopify platform changes and deadlines open or close app opportunities in 2026?

In 2025–2026 Shopify moved its AI-agent endpoints to the Universal Commerce Protocol, gave B2B and customer accounts new surfaces, and set hard end dates for Shopify Scripts, script tags and older catalog and cart APIs. We checked every date against Shopify's developer changelog and Help Center, and list what the AI research report we started from got wrong.

Published 2026-10-11

Key points

Shopify Scripts stopped running on 30 June 2026; published Scripts were deactivated and the replacement is Shopify Functions.
From 1 October 2026 Shopify apps can no longer create or update script tags, and on 1 March 2027 Shopify stops injecting script tags into storefronts for every API version.
Shopify's Storefront Catalog MCP implements the Universal Commerce Protocol on the store's /api/ucp/mcp endpoint, and the older Storefront MCP cart tools were maintained only until 31 August 2026.
Draft-order deposits (API version 2026-07) and the Checkout and Accounts Configuration API (2026-04) are available only to Shopify Plus stores.
Since 16 June 2026, app-owned metafields need a definition with Customer Account API access, or they return no value through that API.

The short answer

The Shopify changes that open room for new apps in 2026 are the move of storefront AI-agent endpoints to the Universal Commerce Protocol (UCP, an open specification for how AI agents query a store's catalog and cart), store credit for B2B company locations, deposits on draft orders, and a single branding API for checkout and customer accounts. The changes that close doors are dated: Shopify Scripts stopped running on 30 June 2026, script tags can no longer be created from 1 October 2026 and stop running on 1 March 2027, the old Storefront MCP cart tools were kept only until 31 August 2026, and the Global Catalog REST API stops on 2 November 2026.

Several of the new surfaces are limited to Shopify Plus or are read-only on the customer side, which narrows who can use an app built on them. We checked each date on 11 October 2026 at Shopify's developer changelog, its documentation or its Help Center.

AI agents: from Storefront MCP to UCP

Catalog. Shopify's changelog lists 22 April 2026 as the date the Storefront Catalog MCP server began implementing the UCP Catalog capability. The current documentation confirms that the Storefront Catalog MCP implements the UCP Catalog capability, exposes the tools search_catalog, lookup_catalog and get_product on the store's /api/ucp/mcp endpoint, and requires an agent profile in every request.

Cart. On 24 June 2026 Shopify deprecated the older Storefront MCP cart tools, get_cart and update_cart, and said it would maintain them until 31 August 2026. The replacements are the UCP Cart MCP tools on the same UCP endpoint, which create, read, update and cancel a cart. On 4 September 2026 Shopify announced that storefronts support UCP version 2026-08-25.

Global Catalog. On 9 October 2026 Shopify announced that the Global Catalog REST API, deprecated in April 2026, stops serving traffic on 2 November 2026. The replacement is the Global Catalog MCP, which also implements UCP.

Outside Shopify. OpenAI launched Instant Checkout in ChatGPT, together with the Agentic Commerce Protocol, on 29 September 2025. In March 2026 OpenAI changed course: it said the first version of Instant Checkout did not offer the flexibility it wanted and that merchants could use their own checkout while it focused on product discovery. For an app builder, the lesson from both platforms is the same: agent-facing endpoints changed several times within a year, so a product that only wraps one endpoint has a short life.

B2B: store credit, payment-method intents and deposits

Store credit per company location. On 15 September 2025, with API version 2025-10, Shopify let B2B company locations own store credit accounts. Merchants can issue credits, refund to credit and manage balances per location in multiple currencies; B2B buyers signed in to the new customer accounts can see and spend that credit at checkout for the locations they may order for.

Payment-method updates. On 26 January 2026 Shopify added an Intents API to customer account UI extensions that lets a buyer replace the payment method on a subscription contract without leaving the extension. Shopify's native flow handles the card details, so the app never stores them.

Deposits on draft orders. On 1 July 2026, with API version 2026-07, Shopify added deposit fields to draft orders. Apps can set a deposit through the Admin API, splitting what is due at checkout from what is due later, for example on fulfilment. The Customer Account API exposes the deposit read-only. The feature is available only to Shopify Plus stores.

Together these let an app build a B2B quote, deposit and credit flow on native objects instead of a parallel invoicing system. The limit is the audience: a deposit-based workflow can be sold only to Plus merchants.

Customer accounts become an app surface

Announcement bar. On 28 August 2025 Shopify added an announcement bar extension for the Thank you page and for customer account pages such as order status, order index and profile, starting with UI extension API version 2025-07.

Market-aware sign-in. On 24 February 2026 Shopify added optional locale and country parameters to the Customer Account API sign-in URL, so headless stores can show the login screen in the right language and market context.

One branding API. On 13 May 2026, with API version 2026-04, Shopify introduced the Checkout and Accounts Configuration API for shared branding across checkout, customer accounts and sign-in, with per-market settings. It replaces the Checkout Branding API and the Checkout Profile API, which are now deprecated, and is available only to Shopify Plus merchants.

Metafield definitions. Since 16 June 2026, app-owned metafields without a definition no longer return a value through the Customer Account API. Apps must create a definition, with Customer Account API access, on each store that installs them. Metafields owned by customers or orders are not affected. On 8 October 2026 Shopify added that every metafield declaration in a checkout or customer account extension needs an owner_type from API version 2027-01, or deployment is blocked.

Doors that closed or are closing

Shopify Scripts. Shopify's changelog set the end of editing and publishing for 15 April 2026 and the end of execution for 30 June 2026. The Help Center now says that any Scripts still published on a store have been deactivated and no longer work, and points merchants to Shopify Functions, either through apps or a custom build.

Script tags. On 24 August 2026 Shopify announced that from 1 October 2026 the scriptTagCreate and scriptTagUpdate mutations return an error, and that on 1 March 2027 Shopify stops injecting script tags into storefronts. The change covers every API version, so pinning an older version does not delay it. The replacements are app embed blocks in theme app extensions, or web pixels for analytics and conversion scripts.

Every app that still relies on a script tag needs a migration before 1 March 2027. Deadlines like these create short-lived demand for migration help and remove apps that are not maintained, which changes the competition in a category without anyone launching anything.

How to read these changes as an app builder

Three questions sort the list. First, who can use the surface: deposits and the branding API are limited to Shopify Plus, which is a small slice of stores. Second, is the buyer-facing side read-only: the deposit is visible to buyers but only an app with Admin access can set it. Third, has the surface already changed once: the AI-agent endpoints changed in April, June, August and October 2026, so an app built on them needs a budget for keeping up.

Deprecations are as useful as launches. A dated end of life, such as the one for script tags, tells you which existing apps must change and when merchants will notice.

Method

We started from an AI deep-research report on Shopify app opportunities created by platform changes and compliance deadlines. We treated every claim as unverified. On 11 October 2026 we checked each Shopify date on the developer changelog entry, the developer documentation or the Help Center, and the OpenAI dates on OpenAI's own announcement pages and their published quotations. We also read the most recent changelog entries and added the closing deadlines the report did not mention: script tags, the Global Catalog REST API and Shopify Scripts.

We dropped all App Store review counts and the report's opportunity scores: review counts change daily and the scores were the report author's own judgement. We could not find at a primary source the report's claims about web pixels on customer account pages or a December 2025 tightening of protected customer data scopes, so they are not included. The regulatory deadlines in the report are covered, with corrections, in our separate EU checklist.

Where the report was wrong

It missed the biggest closing deadlines. The report described only new surfaces. It did not mention that Shopify Scripts stopped on 30 June 2026 or that script tags stop on 1 March 2027, both of which force existing apps and stores to change.

It omitted the plan limits. Draft-order deposits and the Checkout and Accounts Configuration API are available only to Shopify Plus, and the Customer Account API side of deposits is read-only. The report presented them as general building blocks.

It overstated the payment-method feature. The report described native payment-method updates inside customer accounts in general. Shopify's entry is specific to replacing the payment method on a subscription contract.

It treated OpenAI's checkout as an expanding channel. The report cited an expansion of product discovery in April 2026 as momentum for agent checkout. OpenAI's own change in March 2026 moved merchants back to their own checkout. It also dated store credit for company locations only as late 2025; the entry is dated 15 September 2025.

Limitations

The changelog is Shopify's own record and shows when a feature was announced, not when every store received it. Availability by plan, region or API version can change after we checked. We did not test any API ourselves, and we did not measure demand for apps on any of these surfaces. All dates were checked on 11 October 2026.

Sources

Questions and answers

When do Shopify script tags stop working?

Shopify announced on 24 August 2026 that from 1 October 2026 the scriptTagCreate and scriptTagUpdate mutations return an error, and that on 1 March 2027 it stops injecting script tags into storefronts. The change applies to all API versions. Shopify's replacements are app embed blocks in theme app extensions, or web pixels for analytics and conversion tracking.

Do Shopify Scripts still work?

No. Shopify ended editing and publishing of Scripts on 15 April 2026 and ended execution on 30 June 2026. The Help Center says Scripts still published on a store have been deactivated. Merchants recreate the same discounts, shipping and payment customisations with Shopify Functions, through an app from the App Store or a custom app.

What is UCP on Shopify?

UCP, the Universal Commerce Protocol, is an open specification for how AI agents query a store's catalog and cart. Shopify's Storefront Catalog MCP implements its catalog capability on the store's /api/ucp/mcp endpoint with search_catalog, lookup_catalog and get_product tools, and requires an agent profile in each request. Cart tools moved to the UCP Cart MCP.

Can apps set deposits on Shopify draft orders?

Yes, from API version 2026-07, announced on 1 July 2026. Apps set a deposit through the Admin API, splitting the amount due now from the amount due later. Buyers see it through the Customer Account API, which is read-only. The feature is available only to Shopify Plus stores.

What replaced the Checkout Branding API?

The Checkout and Accounts Configuration API, introduced on 13 May 2026 with API version 2026-04. It sets shared branding for checkout, customer accounts and sign-in, with overrides per surface and per market. It replaces the Checkout Branding API and the Checkout Profile API, which are deprecated, and is available only to Shopify Plus merchants.

How to cite this

Going Stellar (2026). Which Shopify platform changes and deadlines open or close app opportunities in 2026?. GOING STELLAR S.R.L..
https://goingstellar.ro/research/shopify-platform-changes-deadlines-2026/

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