# Sending Code or Link via WhatsApp

By default, when the user enters a phone number, we'll send a verification code or magic link using SMS. You can add the option for your users to receive the verification code or link as a WhatsApp message.

## How to Add the WhatsApp Option

![PhoneChannels options](/files/-M4XQyDsEHvFz_lzI2ql)

In your [dashboard](https://dev.cotter.app) > Branding, **select the WhatsApp checkbox** for the Magic Link Form tab and OTP Verification Tab.

![Enabling WhatsApp to send a verification code](/files/-MEjZueJr88m3iLy-DDA)

### WhatsApp Opt-In Requirements

WhatsApp requires that your application implement explicit user opt-ins to deliver messages over WhatsApp. 

{% hint style="info" %}
⚠️[**Read WhatsApp Opt-In Requirements**](https://developers.facebook.com/docs/whatsapp/guides/opt-in/)
{% endhint %}

To do this, we provide the **WhatsApp Button Configuration > Subtitle** to explicitly inform your users that they will be receiving a verification code via WhatsApp. 

The default value for the **Subtitle** is *"If you choose to login with WhatsApp, we will send a WhatsApp message to this number with a verification code"*

{% hint style="danger" %}
We make the **Subtitle** customizable so you can **use a language that your customers understand.** 

Please make sure that your customer is informed that they will be receiving a WhatsApp message, otherwise your application may be suspended.
{% endhint %}


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