How to acquire an opt-in?
Learn the rules for sending notifications through WhatsApp.
Estimated Reading Time: 03 minutes
Each time a notification is sent, either to initiate a conversation with a new user or to resume contact with a user when the 24-hour window for communication has passed, WhatsApp charges for using the template.
Please note that the 24-hour window does not start from the moment the template is submitted. If the user does not respond to the message, this does not open the 24-hour communication window period; this means that no further messages can be sent. If it is necessary to send a second or third template, regardless of whether the window is open or not, you will be charged for sending that notification.
The window opens only if the user responds to the notification. Therefore, WhatsApp will not charge you for the following messages and notifications, as long as they happen within the allowed 24-hour time-frame.
Opt-in
You can start a conversation with your users, even if they have not previously spoken to your company. In this case, you must request a subscription on your website in advance to acquire the appropriate authorization; this can be through a registration form, an email, etc.
For further specification visit Understanding How to Get Opt-in for WhatsApp