What email list hygiene is#
List hygiene is the ongoing removal of invalid, inactive, and risky addresses from a mailing list, plus verification of new addresses at the point of capture.
Why it matters#
Bounces, spam traps, and disengaged recipients are the three fastest ways to damage reputation, and all three are prevented by hygiene.
What Postmark handles#
Most platforms, including Postmark, generate the records or settings you need under a domain authentication or sending settings page, and expose bounce and complaint data in reports. Confirm the exact location in Postmark's current documentation.
What you still own#
- Verify new signups in real time with an API and use double opt-in for marketing lists.
- Suppress hard bounces immediately and soft bounces after 3 consecutive failures.
- Run a re-engagement campaign at 90 days of inactivity and sunset at 180.
- Remove role accounts (info@, sales@) and disposable domains from marketing lists.
- Audit the list quarterly with a bulk verification service.
Common mistakes#
- Importing old exports without verification.
- Keeping unengaged contacts because the list size looks good in reports.
Frequently asked questions#
What is a spam trap?
An address that never opted in, maintained by providers and blocklists to catch senders with poor acquisition practices. Hitting one can blocklist your IP or domain.
What bounce rate is acceptable?
Under 2% hard bounces. Above 5% typically triggers ESP account reviews.
Does Postmark set up email list hygiene automatically?
Postmark provides the values and some checks, but publishing DNS, aligning domains, and monitoring results remain your responsibility.