List health
What is List Hygiene?
The ongoing practice of cleaning a contact list to remove invalid, risky, or unengaged addresses before sending.
List hygiene is the process of validating and pruning a recipient list to remove invalid syntax, dead mailboxes, spam traps, role accounts, and chronically unengaged contacts. It combines pre-send verification, such as MX and SMTP checks, with ongoing suppression of bounces, complainers, and non-responders. Good hygiene lowers bounce and complaint rates, which in turn protects sender reputation and inbox placement.
Why it matters for cold email
Cold lists are often scraped or purchased and carry high rates of invalid addresses and spam traps that can blacklist a domain on the very first send. Verifying and segmenting before sending, then continuously removing non-engagers, is the difference between a durable cold program and one that burns domains.
Related terms
Stop guessing at deliverability.
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