List hygiene is the cheapest deliverability upgrade most teams skip. Use this checklist monthly.
Remove immediately. Hard bounces signal invalid addresses; continued sending trains filters to distrust you.
Retry with limits, then suppress. Chronic soft bounces often mean full mailboxes or greylisting — still not “engaged subscribers.”
Define inactivity (e.g., no open/click in 90–180 days depending on frequency). Run a re-permission campaign once, then sunset non-responders. Your open rate will look “worse” temporarily and your inbox placement often improves.
Be careful with info@, admin@, and legal@ for marketing blasts. Use double opt-in when reputation is fragile. Catch typos at signup with confirmation.
Honor unsubscribes quickly and make the link obvious. Hidden unsubscribe is a short path to spam folder hell.
Tools differ in automation for suppression and sunset flows — that is a legitimate reason to pay for a stronger ESP. See our comparison.