Bounce messages are any Message Delivery Notification (MDN) that indicates that the original message could not be delivered. Any bounce messages related to a mailing list message are counted for the affected subscriber.

Realistically, there is no way to reliably determine that a mailing list message has successfully been delivered to a recipient. As such, SmarterMail does not clear out bounces when a message is delivered to a recipient.

If you would like to have bounces cleared out, the best approach would be to use the bounce threshold settings - "Enable threshold for bounce removal" and "Bounce Threshold (Days)" - which are found on Mailing Lists card of the General page in Domain Settings. With these settings configured for the domain, only bounces that fall within the specified time frame will be counted toward subscriber removal.