What it is
List hygiene keeps the recipient set current, permissioned, and reachable. It combines acquisition controls, suppression, bounce processing, and inactivity policy.
Why it matters
Repeated sends to invalid or unwilling recipients create complaints and negative reputation signals that affect wanted mail too.
How to implement
Record the source and time of consent, confirm risky sign-ups, suppress hard bounces and complaints immediately, and define when inactive recipients stop receiving campaigns.
Common mistakes
- Buying or scraping addresses.
- Re-importing suppressed recipients from another system.
- Retrying permanent failures as though they were temporary.
Verification
Trace sample recipients from acquisition through suppression. Confirm every send path applies the same central suppression data before queueing.
Sources
- Gmail email sender guidelines — Google