Good question! But first, what is a "hard bounce"?
A hard bounce occurs when an email has failed permanently due to an invalid email address.
So how does Tout handle a hard bounce?
(1) If emails are going through ToutApp servers, we manage hard bounces.
(2) If emails are going through your own servers instead, you'll want to check with your SMTP provider. In this case, Tout isn't notified about hard bounces, but your own service provider does, so you will want to check with them to see how this is handled.
Want to set up Tout to go through your own SMTP provider? Just go here.