All Drift Paid plans come with unlimited contacts. Only the free Drift account has a contact limit. If you do go over your contact limit on the free plan, this is what happens:
First and foremost, we will not disable or turn off your ability to have conversations or to capture email addresses.
We will let you know that you are over your contact limit on your Drift dashboard.
Deleting Contacts to Stay Within your Limit
You may decide you'd rather delete contacts. That's perfectly fine!
Contacts can easily be deleted in app in the Contacts view. Simply select the contact(s) that you would like to delete and the option to delete them will appear towards the center of your screen.
You can also choose to delete any and all of the contacts within a segment, from the Segments view. Simply click the name of the desired segment, click Manage members, and finally, click Delete all contacts in segment. You'll see a green success message in the bottom left of your window.
If you're deleting multiple contacts at a time or large segments of contacts, the Contacts/Segments view may take a few minutes to update!