For every contact, we store the date of their most recent subscription.
This information can be useful when dealing with contacts individually – for example, if they contact you to find out more about their subscription.
Finding a contact’s last subscription date
To find the most recent subscription date of a contact navigate to Contacts > Contact Lists > Browse Contacts.
You'll see all contacts within the selected contacts list with information like source type (import, form etc.), subscribe status (subscribed or unsubscribed), subscription date - which is exactly what you're looking for, bounce status (soft or hard) as well as the amount of times the bounce occurred, suppression status and data fields.
If a contact requests to be removed/unsubscribed from a contact list you can easily do that simply by selecting the contact and clicking on the ‘unsubscribe’ button.
Once you unsubscribe them, their subscribe status will change and be highlighted in red.