> ## Documentation Index
> Fetch the complete documentation index at: https://dev.smile.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Customer ready method

> `SmileUI.customerReady()`

<Danger>
  This method is deprecated and will be removed on August 1, 2026. Refer to the [migration guide](/guides/use-cases/custom-frontend/js-sdk-migration#3-update-customer-ready-calls) for instructions on choosing the appropriate replacement.
</Danger>

This method is used to detect when customer identification has completed and is useful for wrapping any code (or other Smile UI methods) that require a logged-in customer. It can also be used to decide when to render a logged-in vs. logged-out state.

## Returns

This method returns a `Promise` that resolves once customer identification has occurred (even if there is no logged-in customer) and does not wait for other dependencies. If customer identification has already occurred, the `Promise` will resolve immediately.

The `Promise` will resolve with:

* On success, a [customer](/ui/objects/customer) object when there is a currently logged-in customer, or `null` if no customer is currently logged-in.
* On failure, an error object.

<Panel>
  ```javascript JavaScript lines theme={null}
  SmileUI.customerReady().then(customer => {
    if (customer) {
      // A customer is logged in
    } else {
      // No customer was identified (user needs
      // to log in or create an account)
    }
  }).catch(err => {
    // An error has occurred will trying to
    // identify a customer
  });
  ```
</Panel>