Emptying a list
When you empty a list, you delete all subscribers from that list at once. The list itself remains in place, including its name, extra fields and sign-up form.
In addition to emptying a list, you can also create, rename, delete or copy a list. Copying is similar, except that it creates a second list alongside your existing list.
The subscribers you delete will remain in the ‘deleted’ tab of the list for 30 days. Within those 30 days, you can restore them all at once using the ‘Restore all’ button. You can read how this works in Restoring deleted subscribers and lists. After those 30 days, they are permanently deleted.
If you want to keep the data, export your subscribers before emptying the list. If you only want to delete some of your subscribers, take a look at Deleting subscribers and Deleting inactive subscribers first.