Doing some spring cleaning? If you’d like to get rid of a list without deleting the contacts themselves, just follow these steps. If you want to delete the contacts permanently from your subscribers, see the instructions, here.
First, make sure you're in your Subscribers area, of your account.
Step 1. Select your list from the left sidebar.
Step 2. Click the little trashcan icon, next to the list name.
Step 3. Click OK to confirm.
Remember! Deleting a list does not delete the contacts contained in the list. Those folks will remain in any other lists they’re members of and in your All contacts list. Learn more, here.