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.
Checkers and validators#
Free lookup tools confirm that records resolve and are syntactically valid. Primary Deliverability runs SPF, DKIM, DMARC, and BIMI checks in one report and flags alignment problems.
Provider dashboards#
Google Postmaster Tools and Microsoft SNDS are free and authoritative for their networks. Register every sending domain and IP.
Report analyzers and monitoring#
DMARC aggregate reports are XML and unreadable by hand; an analyzer turns them into a per-source view. Monitoring services alert on reputation drops, blocklistings, and record changes.
Sending platforms#
Your ESP or outreach tool should expose authentication setup, bounce and complaint handling, and per-mailbox limits. For AI-drafted sequences with reply detection, Mailflow in MailMaid Engine handles the sending side.
How to choose#
- Start with the free provider dashboards and a checker.
- Add a DMARC analyzer once you have more than two sending sources.
- Add monitoring when email is revenue-critical.
- Choose sending platforms by their deliverability controls, not template libraries.
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.