---
title: CartLineCost - Storefront API
description: >
  Cost breakdown for a single line item in a
  [cart](/docs/api/storefront/2026-01/objects/Cart). Includes the per-unit
  price, the subtotal before line-level discounts, and the final total amount
  the buyer pays.


  The
  [`compareAtAmountPerQuantity`](/docs/api/storefront/2026-01/objects/CartLineCost#field-CartLineCost.fields.compareAtAmountPerQuantity)
  field shows the original price when the item is on sale, enabling the display
  of savings to customers.
api_version: 2026-01
api_name: storefront
type: object
api_type: graphql
source_url:
  html: 'https://shopify.dev/docs/api/storefront/latest/objects/CartLineCost'
  md: 'https://shopify.dev/docs/api/storefront/latest/objects/CartLineCost.md'
---

# Cart​Line​Cost

object

Cost breakdown for a single line item in a [cart](https://shopify.dev/docs/api/storefront/2026-01/objects/Cart). Includes the per-unit price, the subtotal before line-level discounts, and the final total amount the buyer pays.

The [`compareAtAmountPerQuantity`](https://shopify.dev/docs/api/storefront/2026-01/objects/CartLineCost#field-CartLineCost.fields.compareAtAmountPerQuantity) field shows the original price when the item is on sale, enabling the display of savings to customers.

## Fields

* amount​Per​Quantity

  [Money​V2!](https://shopify.dev/docs/api/storefront/latest/objects/MoneyV2)

  non-null

  The amount of the merchandise line.

* compare​At​Amount​Per​Quantity

  [Money​V2](https://shopify.dev/docs/api/storefront/latest/objects/MoneyV2)

  The compare at amount of the merchandise line.

* subtotal​Amount

  [Money​V2!](https://shopify.dev/docs/api/storefront/latest/objects/MoneyV2)

  non-null

  The cost of the merchandise line before line-level discounts.

* total​Amount

  [Money​V2!](https://shopify.dev/docs/api/storefront/latest/objects/MoneyV2)

  non-null

  The total cost of the merchandise line.

***

## Map

### Fields with this object

* [BaseCartLine.cost](https://shopify.dev/docs/api/storefront/latest/interfaces/BaseCartLine#fields-cost)
* [CartLine.cost](https://shopify.dev/docs/api/storefront/latest/objects/CartLine#field-CartLine.fields.cost)
* [ComponentizableCartLine.cost](https://shopify.dev/docs/api/storefront/latest/objects/ComponentizableCartLine#field-ComponentizableCartLine.fields.cost)