---
title: cartSetIdDefault
description: Creates a function that returns a header with a Set-Cookie on the cart ID.
api_version: 2025-07
api_name: hydrogen
source_url:
  html: https://shopify.dev/docs/api/hydrogen/latest/utilities/cartsetiddefault
  md: https://shopify.dev/docs/api/hydrogen/latest/utilities/cartsetiddefault.md
---

# cart​Set​Id​Default

Creates a function that returns a header with a Set-Cookie on the cart ID.

## cart​Set​Id​Default([cookieOptions](#cartsetiddefault-propertydetail-cookieoptions)​)

### Parameters

* cookieOptions

  CookieOptions

### CookieOptions

* domain

  ```ts
  string
  ```

* expires

  ```ts
  Date | number | string
  ```

* httponly

  ```ts
  boolean
  ```

* maxage

  ```ts
  number
  ```

* path

  ```ts
  string
  ```

* samesite

  ```ts
  'Lax' | 'Strict' | 'None'
  ```

* secure

  ```ts
  boolean
  ```

```ts
{
  maxage?: number;
  expires?: Date | number | string;
  samesite?: 'Lax' | 'Strict' | 'None';
  secure?: boolean;
  httponly?: boolean;
  domain?: string;
  path?: string;
}
```

Examples

### Examples

* #### example

  ##### Description

  This is the default example

  ##### JavaScript

  ```js
  import {data} from 'react-router';
  import {cartGetIdDefault, cartSetIdDefault} from '@shopify/hydrogen';

  // server.js
  export default {
    async fetch(request) {
      const cart = createCartHandler({
        storefront,
        getCartId: cartGetIdDefault(request.headers),
        setCartId: cartSetIdDefault(), // defaults to session cookie
        // setCartId: cartSetIdDefault({maxage: 60 * 60 * 24 * 365}), // 1 year expiry
      });
    },
  };

  // Some route
  export async function action({context}) {
    const {cart} = context;

    // Usage
    const result = await cart.updateNote('Some note');

    const headers = cart.setCartId(result.cart.id);

    return data(result, {headers});
  }
  ```