Implement email list hygiene — remove hard bounces and unengaged contacts

Email list hygiene means actively removing hard bounces (addresses that no longer exist) and unengaged contacts (people who never open your email) rather than continuing to send to them, since sending to bad or unengaged addresses directly damages your sender reputation.

Mail providers watch engagement rates as a real signal, a list full of dead addresses and disengaged contacts drags down your overall deliverability for everyone on the list, including your genuinely engaged subscribers.

How to do it

1. 1
   Remove hard bounces immediately

   An address that hard bounces once genuinely does not exist, continuing to send to it only hurts your reputation.
2. 2
   Identify genuinely unengaged contacts

   Typically defined as no opens or clicks over 6 to 12 months, depending on your typical sending frequency.
3. 3
   Attempt a re-engagement campaign before removing

   One genuine last attempt to win back attention before cutting someone from the list.
4. 4
   Remove or suppress those who remain unengaged

   Protects your sender reputation for everyone still genuinely receiving and reading your email.