Sending bulk mail without wrecking your reputation
Newsletters and notifications done right: lists, consent, authentication and pacing.
Bulk mail is where most domains destroy their reputation. The rules are simple, and mostly about consent.
Consent is the whole game
Send only to people who asked to hear from you.
Keep a record of when and how each person opted in.
Make unsubscribing one click, and honour it immediately.
Never buy, scrape, or "rent" a list. Not once, ever.
Separate your streams
Do not send transactional mail (password resets, receipts) and bulk marketing from the same domain or IP. A marketing complaint should never put password resets in spam. Use a subdomain or a second domain for marketing.
Authenticate
SPF, DKIM and DMARC on the sending domain — every stream. See Email DNS. Bulk mail without DMARC p=reject increasingly fails provider requirements.
Add List-Unsubscribe headers
One-click unsubscribe via List-Unsubscribe (and List-Unsubscribe-Post) headers is expected by major mailbox providers, and they reward its presence. You also need a visible unsubscribe link in the body.
Pace yourself
Warm up new IPs/domains: start small, grow over days.
Throttle sends rather than blasting millions at once.
Prune hard: remove hard bounces immediately and inactive subscribers after a defined period. Sending to people who never open mail trains filters to distrust you.
Watch the metrics that matter
Bounce rate — over ~2% is a warning; over 5% is a problem.
Complaint rate — keep it well under 0.1%.
Engagement — opens/clicks signal to providers that people want your mail.
Tooling
For self-hosted newsletters, listmonk is excellent (AGPL). For marketing automation, Mautic. Both need correct authentication and a warmed sending path — the software is the easy part.
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