---
title: The cartDiscountCodeUpdate mutation now requires the discountCodes field - 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/the-cartdiscountcodeupdate-mutation-now-requires-the-discountcodes-field
  md: https://shopify.dev/changelog/the-cartdiscountcodeupdate-mutation-now-requires-the-discountcodes-field.md
---

[Back to Developer changelog](https://shopify.dev/changelog)

October 30, 2025

Tags:

* Action Required
* Storefront GraphQL API
* 2026-01

# The `cartDiscountCodeUpdate` mutation now requires the `discountCodes` field

As part of the [GraphQL Storefront API 2026-01 release](https://shopify.dev/docs/api/storefront/2026-01/mutations/cartdiscountcodesupdate), the `cartDiscountCodesUpdate` mutation now requires the `discountCodes` agrument to be included. Previously, the `cartDiscountCodesUpdate` mutation would accept a mutation with no `discountCodes` argument, which would not actually modify the cart in any way.

For more information about the `Cart` object and its related mutations, visit [Shopify.dev](https://shopify.dev/api/storefront/unstable/objects/Cart).