List Hygiene: Sending Less to Earn More
Nobody enjoys removing subscribers. List size is the number that gets reported upward, and cutting it feels like destroying an asset. But mailbox providers decide inbox placement partly on how the people you mail behave, and a large dormant tail drags down delivery for the audience that is still paying attention.
Start at the point of capture
Most list quality problems are created at signup. Add real-time validation on the form, reject known disposable domains, catch the obvious typo domains, and use confirmed opt-in where the list quality matters more than the raw count. Everything you block here is a bounce you never have to clean up.
| Stage | Action | Cadence |
|---|---|---|
| Capture | Syntax check, domain check, typo correction | Real time |
| Ongoing | Remove hard bounces immediately | Every send |
| Ongoing | Suppress after repeated soft bounces | Rolling |
| Periodic | Re-engagement then sunset for dormant | Quarterly |
Write the sunset policy down
A policy removes the argument. For example: subscribers with no open or click in 180 days enter a three-message re-engagement flow; non-responders are suppressed from campaigns but retained in the database. Written down, it runs automatically. Undocumented, it becomes a debate every quarter and never happens.
Suppress rather than delete. You keep purchase history and the record of consent, and you stop sending.
Spam traps and why they matter
Recycled traps are abandoned addresses that providers reactivate specifically to catch senders who never clean their lists. Hitting them is a direct reputation hit. The defence is not a trap-detection service; it is simply not mailing addresses that have shown no sign of life for a year.
Handle the reporting
Agree in advance how you will present the drop. The honest framing is that you are removing addresses that were never going to convert in order to protect delivery to the ones that will. Bring the before-and-after inbox placement figures; they make the case better than any argument.
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