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. Ha…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.