You’ve clicked the ‘unsubscribe’ button. So, now what happens to your email address? Is it just deleted?
The answer is: no, it isn’t deleted. Your email goes to what’s called a ‘suppression list’. A suppression list is a list of emails where the owner doesn’t want marketing communications. Unless you can remember everyone who has opted out, you will need to have a suppression list.
Holding emails in a suppression list when someone has opted out is lawful. Your legal basis is legitimate interest — it is in your legitimate interest to hold that person’s email so that you don’t send them emails in the future and run afoul of the Privacy and Electronic Communications Regulations (PECR).
A person can object to you holding their email in a suppression list after they have opted out but you can decline their request to remove the email.
It is good practice to have a suppression list. Just make sure that you tell people in your Privacy Notice that you have one and are using legitimate interest as the legal basis.
You will need to have a retention period for your suppression list and this will depend upon your business requirements.