Launching a cold email campaign without warming up your domain is like skydiving without a parachute — fast, dangerous, and almost guaranteed to crash.
Warming up your domain is the most important step before sending cold emails. If you skip it, your emails will land in spam, get flagged, or your domain/IP could even get blacklisted.
In this guide, we’ll walk you through exactly how to warm up your domain step-by-step — the right way — so your cold emails actually get delivered, opened, and replied to.
🧠 What Is Domain Warmup?
Domain warmup is the process of gradually building your domain’s sender reputation by sending low volumes of legitimate, engaging emails over time — before you launch a full cold outreach campaign.
Think of it like training before a marathon. You build trust with email providers like Gmail, Outlook, Yahoo, etc., to show you’re not a spammer.
🚀 Step-by-Step Domain Warmup Guide
✅ Step 1: Register a Fresh Domain for Outreach
Never use your main business domain (e.g., frozenreach.com) for cold emailing.
Instead:
- Buy a variation like
getfrozenreach.comorfrozenreachhq.com. - Use this exclusively for outreach.
👉 This protects your main brand reputation in case anything goes wrong.
✅ Step 2: Set Up Proper DNS Authentication (SPF, DKIM, DMARC)
Email providers check your domain’s records to verify legitimacy.
Set up:
- SPF: Authorizes IPs allowed to send emails from your domain.
- DKIM: Digitally signs your emails to prevent spoofing.
- DMARC: Gives ISPs instructions on how to handle unauthenticated emails.
💡 Use tools like MxToolbox to verify your DNS records.
✅ Step 3: Create 1–2 Mailboxes
Set up professional-looking inboxes like:
Avoid generic addresses like sales@ or info@ — they look spammy.
✅ Step 4: Use a Warmup Tool or Manual Strategy
You have two options:
Option A: Use an Automated Warmup Tool
Tools like:
- Mailwarm
- Instantly
- Lemwarm
- Warmbox
- Mailreach
They simulate real email conversations (sending and replying) with other inboxes to build reputation fast.
✅ Pros: Hands-off, fast, smart.
❌ Cons: Paid.
Option B: Manual Warmup
- Start by sending 10–15 emails per day to friends, coworkers, or verified inboxes.
- Write real, short messages.
- Ask recipients to reply — engagement matters.
- Gradually increase by 5–10 emails every few days.
- Track open/reply rates and ensure bounces stay under 3%.
🔄 Keep this up for 2–3 weeks minimum.
✅ Step 5: Gradually Ramp Up Cold Email Volume
After 2–3 weeks of warmup:
- Start cold campaigns with very low volume: 20–30 emails/day.
- Use a high-deliverability SMTP (like FrozenReach’s Cold Email SMTP).
- Continue tracking opens, bounces, and replies.
⚠️ Never jump from 20 to 200 emails overnight. Sudden spikes look suspicious and damage your domain’s reputation.
✅ Step 6: Maintain a Healthy Sending Reputation
Even after warmup, deliverability can drop if you’re careless.
Ongoing best practices:
- Always verify your lead list.
- Avoid spammy keywords and aggressive language.
- Respect opt-outs and replies.
- Monitor bounce/spam reports regularly.
🔥 Bonus Tips
- 📨 Use plain-text emails with minimal links or attachments.
- 📆 Send during business hours, not weekends or holidays.
- 🧪 A/B test subject lines — low open rates may hurt deliverability.
- 🎯 Use multiple inboxes across domains if scaling.
🧊 FrozenReach Pro Tip
We offer done-for-you domain warmup services along with:
✅ Domain setup
✅ Authentication
✅ Mailboxes
✅ Warmup automation
✅ Ongoing deliverability monitoring
👉 [Let Us Warm Up Your Domain — Start Now »]
✍️ Conclusion
Domain warmup isn’t optional — it’s essential.
If you want your cold emails to land in inboxes (and not get buried in spam), follow this step-by-step warmup plan carefully.
Investing just 2–3 weeks upfront can save months of frustration and lost leads.
Whether you’re a founder, marketer, or agency, start your outreach the right way — with a domain that’s trusted, warm, and ready to deliver.