The Cold Email Deliverability Checklist: 25 Checks Before You Hit Send

Most deliverability problems are avoidable, and most are caused by skipping one boring step. Run through this checklist before every new campaign or new batch of inboxes. Bookmark it, copy it into your launch doc, share it with your team.

Domains

1. Cold email is sent from separate domains, never your main company domain.
2. Domains are close variations of your brand (getacme.com, tryacme.com), ideally .com.
3. Every domain redirects to your main website.
4. Domains were registered at least a couple of weeks before sending.

Authentication

5. SPF is published and includes only the services you actually send from.
6. DKIM is enabled and passing for every sending domain.
7. DMARC is published (p=none is fine to start) with a reporting address.
8. The From domain aligns with SPF or DKIM. See what Gmail, Yahoo and Microsoft require.
9. A custom tracking domain is set up, or tracking is off.

Inboxes

10. Two or three inboxes per domain, not ten.
11. Each inbox has a real name, profile photo and signature.
12. You have enough inboxes for your volume at 30 to 50 emails each per day. Use this formula.
13. Inboxes are on reputable infrastructure (Google Workspace or Microsoft 365), not a cheap shared SMTP pool.

Warmup

14. New inboxes have been warming for two to four weeks. See the timeline.
15. Warmup stays on while campaigns run.
16. An inbox placement test shows you landing in the primary inbox.

List

17. Every address is verified within the last 30 days.
18. Expected bounce rate is under 2%.
19. The list is tightly targeted. Relevance is the best protection against spam complaints.
20. Unsubscribes and "not interested" replies from past campaigns are suppressed.

Copy

21. Plain text, at most one link, no attachments or images in the first email.
22. The first line is genuinely personalised, and you use a few variants rather than one identical email.
23. There is an easy way to opt out, and you honour it.

Sending and monitoring

24. Volume ramps up over the first week of a campaign instead of starting at full speed.
25. You check bounces, replies and Google Postmaster Tools weekly, and pause any inbox that starts landing in spam.

When something goes wrong

If placement drops, work through the 12 most common causes. Pause the affected inboxes, fix the cause and keep warmup running until tests come back clean.

Tick half the list automatically

inboxy handles checks 5 to 7, 13, 14 and 15 for you: Google Workspace mailboxes with SPF, DKIM and DMARC configured, free connection to your sequencer and warmup with real inboxes, at a flat $3 per mailbox a month. See pricing.