What commerce operators should check this week.

A free, source-backed operating brief. This issue contains only reviewed changes with a concrete audience and action; empty sections are stated instead of filled with unverified news.

01 · High-impact changes

Changes worth opening

DeprecationSep 11, 2026confirmed

Customer Address APIs adopt ISO countryCode; territoryCode deprecated in 2026-10

CustomerAddressInput and CustomerAddress gain a countryCode field taking ISO 3166-1 alpha-2 values (US, CA) across the Customer Account API and Checkout UI surfaces, effective September 8, 2026. The existing territoryCode field is deprecated in API version 2026-10 but keeps working with no removal deadline announced. Apps adopting 2026-10 should switch address reads/writes to countryCode and retest address flows.

DeprecationSep 11, 2026confirmed

Discounts Allocator Function API removed after preview; apps must drop the extension target or deploys fail

The Discounts Allocator Function API developer preview ended without release: the discountsAllocatorFunctionRegister/Unregister mutations are removed from the unstable Admin GraphQL API, previously registered functions are auto-unregistered, and the docs are gone. From September 29, 2026 any app still declaring the purchase.discounts-allocator.run extension target fails shopify app deploy for the whole app with an API-not-found error. Shopify points affected use cases at the released Discount Function API.

Api ChangeSep 11, 2026confirmed

Product variants support multiple barcodes; legacy barcode field deprecated in Admin GraphQL 2026-10

Admin GraphQL API 2026-10 lets a product variant carry up to 20 barcodes (255 chars each, optional UPC/EAN/ISBN/GTIN/ASIN type validation) via a new barcodes connection and barcodes input on productSet and the variant bulk mutations. The legacy single barcode field is deprecated: reads return only the first barcode and writes update only the first position, so integrations that sync identifiers can silently drop data once variants carry multiple barcodes. Removal date not yet announced.

02 · Fees, payouts and refunds

Settlement-adjacent changes

No reviewed signal in this issue names a payout or report category.

03 · What to check this week

Concrete next actions

Shopify
When upgrading to 2026-10, replace territoryCode references with countryCode (alpha-2 values) in address integrations and retest customer address operations.View reasoning →
Shopify
Remove the purchase.discounts-allocator.run extension target from app configuration before September 29, 2026, and rebuild the logic on the Discount Function API — otherwise every deploy of the app fails.View reasoning →
Shopify
Move barcode reads to the barcodes connection and writes to the barcodes input before adopting 2026-10, so multi-barcode variants do not silently lose identifier data in syncs.View reasoning →

04 · Upcoming deadlines

Changes with a clock

2026-09-29Discounts Allocator Function API removed after preview; apps must drop the extension target or deploys fail

05 · Report format and operations

Fields and workflows changing

No reviewed report-schema change appears in this issue.

06 · Original sources

Verify at the source

Customer Address APIs adopt ISO countryCode; territoryCode deprecated in 2026-10shopify.dev ↗Discounts Allocator Function API removed after preview; apps must drop the extension target or deploys failshopify.dev ↗Product variants support multiple barcodes; legacy barcode field deprecated in Admin GraphQL 2026-10shopify.dev ↗

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