A hard bounce refers to an email sent to a non-existent, incorrect, or invalid email address due to a permanent error. Such emails are not delivered and instead returns a bounce error.
Hard email bounce may be due to a non-existent recipient email address or a complete delivery block on the recipient email server.
Your deliverability is at risk if your email list comprises a high volume of email addresses that return hard bounces. Most spam filters identify this as a red flag. But with Campaign Monitor, you can automatically remove hard bounces from your email list so you don’t get to send them messages anymore.
Soft bounces are not as damaging to sender reputation as hard bounces, but having good list hygiene is considered a top email marketing best practice.