Kaspersky “support”: +1-888-238-0999
Webroot “support”: +1-877-301-0214
Norton “support”: +1-855-536-5666
Norton “support”: +1-877-301-0214 (most likely dead)
Avast “support”: +1-855-254-6999
QuickBooks “support”: +1-888-499-5520
McAfee “support”: +1-833-202-8208
Found them while browsing around Twitter.
Query: https://twitter.com/search?q=antivirus%20toll%20free