Cold email deliverability: the 12-point pre-send checklist

Deliverability is binary: either your email reaches the inbox or nothing else you did matters. The subject line, the copy, the offer — all irrelevant in the spam folder. Run this checklist before your first send, and again any time reply rates drop.

Infrastructure (do once)

1. SPF record set. Tells receivers which servers may send for your domain. One line of DNS; without it you fail authentication instantly.
2. DKIM signing on. Cryptographic proof the mail wasn't tampered with. Gmail and Yahoo require it for bulk senders since 2024.
3. DMARC policy published. Start with p=none and monitoring; move to quarantine once reports are clean. Receivers now distrust domains without it.
4. Separate sending domain. Cold outreach lives on a cousin domain (get-yourbrand.com), never your primary. If reputation burns, your product email survives.
5. Domain aged 30+ days, with a real page on it and normal traffic. New domain = spam suspect. (More in how many cold emails per day.)

List quality (do every time)

6. Verify every address before sending. Hard bounces above ~3% mark you as a list-buyer. Verification is cheap; a burned domain is not.
7. No catch-all gambling. "Accept-all" domains can't be verified — segment them and send at low volume, or skip.
8. Suppress past bounces and unsubscribes permanently. Re-mailing a hard bounce is self-harm.

Sending behavior

9. Warm up before volume. 10–20/day for two weeks on any new mailbox, ramping only while bounces stay low.
10. Pace like a human. Sends spread across the workday with jitter — not 200 emails at 9:00:00 sharp.
11. Stop on reply, always. Sequences that keep firing after an answer generate spam reports, and one report outweighs a hundred silent deletes.

Content

12. Send text, not a brochure. Minimal HTML, at most one link, no tracking-heavy footers, no attachment on the first touch. Spam-trigger vocabulary is listed in our subject lines guide.

The monitoring loop

Deliverability isn't set-and-forget. Watch three numbers weekly: bounce rate (<2%), reply rate trend (a sudden drop at stable volume = spam placement), and spam-folder tests to seed accounts you control.

If placement slips: halve volume, tighten to your best-verified segment, and rebuild slowly. Reputation recovers on the scale of weeks, not days — which is why every item above is cheaper as prevention than as cure.