cart.updated

Lines, coupons or shipping changed, at once, before the server prices them.

CODE

next.on('cart.updated', (data, event) => {});

Data

Present: always; optional when it may be missing; campaign once the campaign is loaded; priced once the server priced the cart.

Field	Type	Present
`lines`	`CartItem[]`	always	Every line in the cart, the same package's lines merged.
`coupons`	`string[]`	always	The codes the shopper applied, uppercase. A bundle card's own codes are not listed.
`currency`	`string`	campaign	ISO 4217, such as `USD`.
`shipping_method`	`ShippingMethod`	optional	The selected shipping method, and what shipping costs.
`subtotal`	`number`	priced	The products before discounts, without shipping.
`total_discount`	`number`	priced	The discounts on the products, without shipping's: the sum of `discounts`.
`total`	`number`	priced	What the shopper pays.
`discounts`	`Discount[]`	priced	The discounts on the products, one per offer.
`discount_percentage`	`number`	priced	`total_discount ÷ subtotal × 100`, to two decimals; `0` without a discount.
`quantity`	`number`	always	Units in the cart: each line's quantity.

CartItem

A line of the cart. Its prices are there once the server priced the cart.

Field	Type	Present
`package_id`	`number`	always	The package's `ref_id` in the campaign.
`quantity`	`number`	always	Package quantity.
`is_upsell`	`boolean`	optional	`true` for a line added after the order.
`properties`	`Record<string, string>`	optional	Line properties, such as a variant picked in a bundle slot.
`product_id`	`number`	campaign	The product in the store.
`product_title`	`string`	campaign	The product's name as customers see it, as on an order line; the package's name for a package without one.
`variant_id`	`number`	campaign	The product variant, for a product with variants.
`variant_title`	`string`	campaign	The variant's name, such as `Black / M`, for a product with variants.
`sku`	`string`	campaign	The product's Stock Keeping Unit.
`image`	`string`	campaign	The package's image URL.
`price`	`number`	priced	What one package costs after discounts.
`original_price`	`number`	priced	What one package costs before discounts; equal to `price` when nothing is taken off.
`total_discount`	`number`	priced	The discount on the line.
`total`	`number`	priced	`price × quantity`.
`subtotal`	`number`	priced	The line before discounts: `total = subtotal − total_discount`.
`discount_percentage`	`number`	priced	`total_discount ÷ subtotal × 100`, to two decimals; `0` without a discount.
`discounts`	`Discount[]`	priced	The discounts on the line.
`subscription`	`Subscription`	campaign	For a package billed again every interval.

ShippingMethod

The selected shipping method, and what shipping costs.

Field	Type	Present
`id`	`number`	always	The method's `ref_id`.
`code`	`string`	campaign	Such as `standard`.
`name`	`string`	priced	The method's name.
`price`	`number`	priced	What shipping costs after discounts; `0` is free shipping.
`original_price`	`number`	priced	What shipping costs before discounts.
`discounts`	`Discount[]`	priced	The discounts on shipping, such as a free-shipping offer.

Discount

A discount on the cart's products or on its shipping. Amounts are in the cart's currency.

Field	Type	Present
`name`	`string`	always	The offer's name.
`amount`	`number`	always	The amount taken off.
`source`	`"offer"` \| `"coupon"`	always	`coupon` for a code the shopper entered (it is in `coupons`); `offer` for an automatic offer or a bundle card's own code.
`code`	`string`	optional	The code, for a coupon.
`offer_id`	`number`	always	The offer that gave it.
`percentage`	`number`	optional	The percentage the offer is set to take off, as the API reports it, such as `20`. Its configured value, for a label such as “20% off”; the amount actually taken off is `amount`.

Subscription

A package billed again every interval.

Field	Type	Present
`interval`	`"day"` \| `"month"`	always	The unit of the renewal interval.
`interval_count`	`number`	always	How many `interval`s between renewals.
`price`	`number`	priced	What each renewal charges, after discounts.
`original_price`	`number`	priced	What each renewal charges before discounts.

Example

The second argument, with data inside. See Events for the envelope's fields.

CODE

{
  "event_id": "3f2b8c1d9e7a4b6c8d5e2f1a0b9c8d7e",
  "event_type": "cart.updated",
  "object": "cart",
  "data": {
    "lines": [
      {
        "package_id": 1,
        "quantity": 1,
        "product_id": 400,
        "product_title": "Olympus Earbuds",
        "variant_id": 4001,
        "variant_title": "Black",
        "image": "https://cdn.test/1.png"
      },
      {
        "package_id": 2,
        "quantity": 1,
        "product_id": 400,
        "product_title": "Olympus Earbuds",
        "variant_id": 4002,
        "variant_title": "Black",
        "image": "https://cdn.test/2.png"
      }
    ],
    "coupons": [],
    "quantity": 2,
    "currency": "USD"
  },
  "created_at": "2026-11-04T08:30:00.000Z",
  "session_id": "0b8f3c2d1e4a4f6b9c7d5e3f2a1b0c9d",
  "sdk_version": "0.5.0"
}