---
title: CartLinesAddPayload - Storefront API
description: Return type for `cartLinesAdd` mutation.
api_version: 2026-04
source_url:
  html: 'https://shopify.dev/docs/api/storefront/latest/payloads/CartLinesAddPayload'
  md: >-
    https://shopify.dev/docs/api/storefront/latest/payloads/CartLinesAddPayload.md
api_name: storefront
api_type: graphql
type: payload
---

# Cart​Lines​Add​Payload

payload

Return type for `cartLinesAdd` mutation.

## Fields

* cart

  [Cart](https://shopify.dev/docs/api/storefront/latest/objects/Cart)

  The updated cart.

* user​Errors

  [\[Cart​User​Error!\]!](https://shopify.dev/docs/api/storefront/latest/objects/CartUserError)

  non-null

  The list of errors that occurred from executing the mutation.

* warnings

  [\[Cart​Warning!\]!](https://shopify.dev/docs/api/storefront/latest/objects/CartWarning)

  non-null

  A list of warnings that occurred during the mutation.

***

## Mutations with this payload

* [cart​Lines​Add](https://shopify.dev/docs/api/storefront/latest/mutations/cartLinesAdd)

  mutation

  Adds one or more merchandise lines to an existing [`Cart`](https://shopify.dev/docs/api/storefront/2026-04/objects/Cart). Each line specifies the [product variant](https://shopify.dev/docs/api/storefront/2026-04/objects/ProductVariant) to purchase. Quantity defaults to `1` if not provided.

  You can add up to 250 lines in a single request. Use [`CartLineInput`](https://shopify.dev/docs/api/storefront/2026-04/input-objects/CartLineInput) to configure each line's merchandise, quantity, selling plan, custom attributes, and any parent relationships for nested line items such as warranties or add-ons.

  * cart​Id

    [ID!](https://shopify.dev/docs/api/storefront/latest/scalars/ID)

    required

    ### Arguments

    The ID of the cart.

  * lines

    [\[Cart​Line​Input!\]!](https://shopify.dev/docs/api/storefront/latest/input-objects/CartLineInput)

    required

    A list of merchandise lines to add to the cart.

    The input must not contain more than `250` values.

  ***

***

## Map

### Mutations with this payload

* [cart​Lines​Add](https://shopify.dev/docs/api/storefront/latest/mutations/cartLinesAdd)