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

# Member access and login

> Configure how members authenticate and log in to your rewards program widgets.

<Note>
  Related articles:
  [Member opt-in & enrollment](/program/program-setup/member-opt-in-enrollment), [Custom customer authentication](/integrations/custom-customer-authentication), [Shopify](/integrations/shopify)
</Note>

The authentication method determines how members log in to your rewards program widgets. Choose a method that matches your store setup.

Navigate to [Settings -> Rewards program -> General](https://app.cevoid.com/settings/program) to configure authentication settings.

<Tip>
  Use your store's existing login system for the most native experience. Cevoid's passwordless email login is a great alternative when your store doesn't have its own login system.
</Tip>

***

## Available authentication methods

| Authentication method              | Best for                                                           | How members log in                                        |
| ---------------------------------- | ------------------------------------------------------------------ | --------------------------------------------------------- |
| **Shopify customer account**       | Shopify stores                                                     | Members use their Shopify store account credentials       |
| **Cevoid email authentication**    | Stores without a login system                                      | Members enter their email and receive a verification code |
| **Custom customer authentication** | General implementation, headless setups, and non-Shopify platforms | Members are authenticated through your own system         |

***

## Shopify customer account authentication

Members log in using their existing Shopify store account credentials. This provides a native experience where members use the same login they use for the rest of your store.

<Note>
  This method works with both Shopify legacy customer accounts and new customer accounts. Some opt-in rules are only available with legacy accounts. See [Member opt-in & enrollment](/program/program-setup/member-opt-in-enrollment) for details.
</Note>

***

## Cevoid email authentication

Members log in using a passwordless email flow. They enter their email address and receive a verification code to complete authentication.

This method is ideal when your store doesn't have its own customer account system.

***

## Custom customer authentication

Members are authenticated through your own system. This method is for general implementation, headless setups, and stores running on platforms other than Shopify where you want to connect your existing user system with Cevoid.

This method requires server-side implementation. Encrypt a payload with a key provided by Cevoid and attach the result to your widget embed code.

See [Custom customer authentication](/integrations/custom-customer-authentication) for full implementation instructions.

***

## Change the authentication method

1. Navigate to [Settings -> Rewards program -> General](https://app.cevoid.com/settings/program)
2. Find the *Authentication* dropdown under *Access and enrollment*
3. Select your preferred method
4. Click **Save**

<Warning>
  Changing your authentication method may affect how existing members access their accounts. Test before switching methods on a live program.
</Warning>