---
title: Storage
description: The API for interacting with local storage.
api_version: 2026-01
api_name: checkout-ui-extensions
source_url:
  html: https://shopify.dev/docs/api/checkout-ui-extensions/latest/apis/storage
  md: https://shopify.dev/docs/api/checkout-ui-extensions/latest/apis/storage.md
---

# Storage

The API for interacting with local storage.

## StandardApi

The base API object provided to `purchase` extension targets.

* **storage**

  **Storage**

  **required**

  The key-value storage for the extension.

  It uses `localStorage` and should persist across the customer's current checkout session.

  **Caution:** Data persistence isn\'t guaranteed and storage is reset when the customer starts a new checkout.

  Data is shared across all activated extension targets of this extension. In versions 2023-07 and earlier, each activated extension target had its own storage.

### Storage

A key-value storage object for the extension. Stored data is only available to this specific extension and any of its instances. The storage backend is implemented with \`localStorage\` and should persist across the buyer's checkout session. However, data persistence isn't guaranteed.

* delete

  Delete stored data by key.

  ```ts
  (key: string) => Promise<void>
  ```

* read

  Read and return a stored value by key. The stored data is deserialized from JSON and returned as its original primitive. Returns \`null\` if no stored data exists.

  ```ts
  <T = unknown>(key: string) => Promise<T>
  ```

* write

  Write stored data for this key. The data must be serializable to JSON.

  ```ts
  (key: string, data: any) => Promise<void>
  ```

## use​Storage()

Returns the key-value `Storage` interface for the extension target.

### Returns

* **Storage**

  ### ### StorageA key-value storage object for the extension.Stored data is only available to this specific extension and any of its instances.The storage backend is implemented with `localStorage` and should persist across the buyer's checkout session. However, data persistence isn't guaranteed.

  * **delete**

    **(key: string) => Promise\<void>**

    Delete stored data by key.

  * **read**

    **\<T = unknown>(key: string) => Promise\<T>**

    Read and return a stored value by key.

    The stored data is deserialized from JSON and returned as its original primitive.

    Returns `null` if no stored data exists.

  * **write**

    **(key: string, data: any) => Promise\<void>**

    Write stored data for this key.

    The data must be serializable to JSON.

### Storage

A key-value storage object for the extension. Stored data is only available to this specific extension and any of its instances. The storage backend is implemented with \`localStorage\` and should persist across the buyer's checkout session. However, data persistence isn't guaranteed.

* delete

  Delete stored data by key.

  ```ts
  (key: string) => Promise<void>
  ```

* read

  Read and return a stored value by key. The stored data is deserialized from JSON and returned as its original primitive. Returns \`null\` if no stored data exists.

  ```ts
  <T = unknown>(key: string) => Promise<T>
  ```

* write

  Write stored data for this key. The data must be serializable to JSON.

  ```ts
  (key: string, data: any) => Promise<void>
  ```

Examples

### Examples

* #### Storage

  ##### Preact

  ```jsx
  import '@shopify/ui-extensions/preact';
  import {render} from 'preact';
  import {useEffect, useState} from 'preact/hooks';

  export default function extension() {
    render(<Extension />, document.body);
  }

  function Extension() {
    const {storage} = shopify;
    const [tosConsent, setTosConsent] =
      useState(false);

    useEffect(() => {
      async function readFromStorage() {
        const tosConsent = await storage.read(
          'tos-consent',
        );

        setTosConsent(Boolean(tosConsent));
      }

      readFromStorage();
    }, [storage]);

    async function cacheConsent(value: boolean) {
      setTosConsent(value);
      await storage.write('tos-consent', value);
    }

    return (
      <s-checkbox
        checked={tosConsent}
        onChange={() => cacheConsent(!tosConsent)}
        label="I agree with the terms of service"
      />
    );
  }
  ```

## Related

[Reference - Targets](https://shopify.dev/docs/api/checkout-ui-extensions/targets)

[Reference - Components](https://shopify.dev/docs/api/checkout-ui-extensions/components)

[Reference - Configuration](https://shopify.dev/docs/api/checkout-ui-extensions/configuration)

[Learn - Tutorials](https://shopify.dev/apps/checkout)