---
title: BaseCartLine - Storefront API
description: Represents a cart line common fields.
api_version: 2025-10
api_name: storefront
type: interface
api_type: graphql
source_url:
  html: https://shopify.dev/docs/api/storefront/latest/interfaces/BaseCartLine
  md: https://shopify.dev/docs/api/storefront/latest/interfaces/BaseCartLine.md
---

# Base​Cart​Line

interface

Represents a cart line common fields.

## Fields

* attribute

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

  An attribute associated with the cart line.

* attributes

  [\[Attribute!\]!](https://shopify.dev/docs/api/storefront/latest/objects/Attribute)

  non-null

  The attributes associated with the cart line. Attributes are represented as key-value pairs.

* cost

  [Cart​Line​Cost!](https://shopify.dev/docs/api/storefront/latest/objects/CartLineCost)

  non-null

  The cost of the merchandise that the buyer will pay for at checkout. The costs are subject to change and changes will be reflected at checkout.

* discount​Allocations

  [\[Cart​Discount​Allocation!\]!](https://shopify.dev/docs/api/storefront/latest/interfaces/CartDiscountAllocation)

  non-null

  The discounts that have been applied to the cart line.

* id

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

  non-null

  A globally-unique ID.

* merchandise

  [Merchandise!](https://shopify.dev/docs/api/storefront/latest/unions/Merchandise)

  non-null

  The merchandise that the buyer intends to purchase.

* quantity

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

  non-null

  The quantity of the merchandise that the customer intends to purchase.

* selling​Plan​Allocation

  [Selling​Plan​Allocation](https://shopify.dev/docs/api/storefront/latest/objects/SellingPlanAllocation)

  The selling plan associated with the cart line and the effect that each selling plan has on variants when they're purchased.

* estimated​Cost

  [Cart​Line​Estimated​Cost!](https://shopify.dev/docs/api/storefront/latest/objects/CartLineEstimatedCost)

  non-nullDeprecated

***

## Types implemented in

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

  OBJECT

  Represents information about the merchandise in the cart.

  * attribute

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

    An attribute associated with the cart line.

  * attributes

    [\[Attribute!\]!](https://shopify.dev/docs/api/storefront/latest/objects/Attribute)

    non-null

    The attributes associated with the cart line. Attributes are represented as key-value pairs.

  * cost

    [Cart​Line​Cost!](https://shopify.dev/docs/api/storefront/latest/objects/CartLineCost)

    non-null

    The cost of the merchandise that the buyer will pay for at checkout. The costs are subject to change and changes will be reflected at checkout.

  * discount​Allocations

    [\[Cart​Discount​Allocation!\]!](https://shopify.dev/docs/api/storefront/latest/interfaces/CartDiscountAllocation)

    non-null

    The discounts that have been applied to the cart line.

  * id

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

    non-null

    A globally-unique ID.

  * instructions

    [Cart​Line​Instructions!](https://shopify.dev/docs/api/storefront/latest/objects/CartLineInstructions)

    non-null

    The instructions for the line item.

  * merchandise

    [Merchandise!](https://shopify.dev/docs/api/storefront/latest/unions/Merchandise)

    non-null

    The merchandise that the buyer intends to purchase.

  * parent​Relationship

    [Cart​Line​Parent​Relationship](https://shopify.dev/docs/api/storefront/latest/objects/CartLineParentRelationship)

    The parent of the line item.

  * quantity

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

    non-null

    The quantity of the merchandise that the customer intends to purchase.

  * selling​Plan​Allocation

    [Selling​Plan​Allocation](https://shopify.dev/docs/api/storefront/latest/objects/SellingPlanAllocation)

    The selling plan associated with the cart line and the effect that each selling plan has on variants when they're purchased.

  * estimated​Cost

    [Cart​Line​Estimated​Cost!](https://shopify.dev/docs/api/storefront/latest/objects/CartLineEstimatedCost)

    non-nullDeprecated

* [Componentizable​Cart​Line](https://shopify.dev/docs/api/storefront/latest/objects/ComponentizableCartLine)

  OBJECT

  Represents information about the grouped merchandise in the cart.

  * attribute

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

    An attribute associated with the cart line.

  * attributes

    [\[Attribute!\]!](https://shopify.dev/docs/api/storefront/latest/objects/Attribute)

    non-null

    The attributes associated with the cart line. Attributes are represented as key-value pairs.

  * cost

    [Cart​Line​Cost!](https://shopify.dev/docs/api/storefront/latest/objects/CartLineCost)

    non-null

    The cost of the merchandise that the buyer will pay for at checkout. The costs are subject to change and changes will be reflected at checkout.

  * discount​Allocations

    [\[Cart​Discount​Allocation!\]!](https://shopify.dev/docs/api/storefront/latest/interfaces/CartDiscountAllocation)

    non-null

    The discounts that have been applied to the cart line.

  * id

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

    non-null

    A globally-unique ID.

  * line​Components

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

    non-null

    The components of the line item.

  * merchandise

    [Merchandise!](https://shopify.dev/docs/api/storefront/latest/unions/Merchandise)

    non-null

    The merchandise that the buyer intends to purchase.

  * quantity

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

    non-null

    The quantity of the merchandise that the customer intends to purchase.

  * selling​Plan​Allocation

    [Selling​Plan​Allocation](https://shopify.dev/docs/api/storefront/latest/objects/SellingPlanAllocation)

    The selling plan associated with the cart line and the effect that each selling plan has on variants when they're purchased.

  * estimated​Cost

    [Cart​Line​Estimated​Cost!](https://shopify.dev/docs/api/storefront/latest/objects/CartLineEstimatedCost)

    non-nullDeprecated

***

```json
{
	"attribute": {
		"key": ""
	},
	"attributes": "",
	"cost": "",
	"discountAllocations": "",
	"estimatedCost": "",
	"id": "",
	"merchandise": "",
	"quantity": "",
	"sellingPlanAllocation": ""
}
```

##### Variables

```
{
	"attribute": {
		"key": ""
	},
	"attributes": "",
	"cost": "",
	"discountAllocations": "",
	"estimatedCost": "",
	"id": "",
	"merchandise": "",
	"quantity": "",
	"sellingPlanAllocation": ""
}
```

##### Schema

```
interface BaseCartLine {
  attribute: Attribute
  attributes: [Attribute!]!
  cost: CartLineCost!
  discountAllocations: [CartDiscountAllocation!]!
  estimatedCost: CartLineEstimatedCost!
  id: ID!
  merchandise: Merchandise!
  quantity: Int!
  sellingPlanAllocation: SellingPlanAllocation
}
```