Suppression List
The do-not-email list: unsubscribes, bounces, complaints. Your ESP maintains it automatically; importing around it is the cardinal sin.
Free · no signup · last reviewed August 29, 2026
The definition
The do-not-email list: unsubscribes, bounces, complaints. Your ESP maintains it automatically; importing around it is the cardinal sin.
Why it matters to an owner
When switching ESPs, migrate the suppression list FIRST. Accidentally re-mailing people who unsubscribed is a complaint spike with legal edges.
Keep going
Email Service Provider (ESP)The platform that sends your marketing email. Mailchimp, Klaviyo, ConvertKit, and kin. Han…Spam Complaint RateThe share of recipients clicking 'report spam.' Gmail's bulk-sender threshold: stay under …List HygieneThe practice of keeping an email list clean: removing bounces, validating addresses, sunse…
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Everything here is free to use yourself. That’s the point. If you’d rather a senior marketer just handle it, in your accounts and your name: 20-minute call, no pitch deck.