Domain Warm-Up for Cold Email: What to Do After an Infra Reset

You've made the decision to replace burned infrastructure with fresh domains and inboxes. Done correctly, you'll have campaigns running cleanly within 4–6 weeks. Done wrong, you'll burn the new infrastructure before campaigns even start. Here's the right approach.

Before you buy new domains

The most important thing to do before purchasing replacement domains is understanding why the previous infrastructure burned. If you don't fix the root cause — list quality, sending volume, authentication issues, or tracking configuration — you'll burn the new domains on the same timeline as the old ones.

Root causes to identify and fix before reset:

Was list quality the problem? (high bounce rates, complaints)
Was sending volume too high? (volume spikes, too many inboxes per domain)
Was tracking configured incorrectly? (Cloudflare proxy, domain sharing)
Was authentication broken? (missing DKIM, SPF issues)

New domain selection and setup

Domain selection

Buy from reputable registrars (Namecheap, GoDaddy, Google Domains)
Avoid aged domains with unknown history unless from a verified source
The domain doesn't need to be creative — it needs to be clean
Create a basic website or redirect to your business site
Set up professional email hosting (GWS, M365, or custom SMTP)

Authentication setup (day 1)

Do this before any warmup send:

SPF: v=spf1 include:[your-esp-include] ~all
DKIM: enable in your ESP, publish DNS record, verify with DKIM checker
DMARC: v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com
MX: configure for reply receipt
Redirect: http → https, both root and www

Verify all of these before the first warmup email. Use the warmup readiness checker.

Tracking domain setup

Set up a fresh tracking domain — separate from your sending domain. Configure the CNAME for your ESP without Cloudflare proxying. Verify SSL is working. Check with the tracking domain checker.

The warmup process

Week 1 (days 1–7)

2–3 emails per day per inbox
Use warmup tool to establish initial sending pattern
Supplement with real exchanges where possible
Monitor bounce rates — should be near zero at this stage

Week 2–3 (days 8–21)

Ramp to 5–8 emails per day
Continue warmup tool sends
Run a placement test at end of week 2
If test shows spam — pause and diagnose immediately

Week 4+ (days 22+)

Ramp to provider limit (GWS: 15/day, M365: 10/day)
Run placement test before first live campaign
Start campaigns at 50% of normal volume for the first week
Monitor bounce and open rates closely

What to do with old infrastructure

Don't abandon burned domains — use them productively:

Submit blacklist delisting requests immediately
Fix any authentication issues
Let them sit for 4–8 weeks while new infrastructure warms up
After delisting is confirmed and reputation has had time to recover, add to backup pool
Use recovered domains for lower-risk sequences (follow-ups, not initial outreach)

If your campaign timeline can't accommodate a 4–6 week warmup, pre-warmed inboxes from WarmInboxes are the alternative. They skip the warmup period entirely — but the infrastructure hygiene (auth, tracking, limits) still needs to be correct for them to maintain their placement quality.