Cold Email Deliverability Checklist: 17 Things to Check

9 min read

Cold Email Deliverability Checklist — 17 Things to Check Before Sending

Your cold email campaign is ready. You've written compelling copy, identified your targets, set up your sequences. But if your emails land in spam, none of it matters.

Here's the complete checklist for cold email deliverability. Check every item before hitting send.

Domain Setup and Authentication

☐ 1. Your Domain Is At Least 30 Days Old

Why it matters: Brand new domains sending cold emails is the #1 sign of a spammer. ISPs don't trust domains registered yesterday.

How to check: 

whois yourdomain.com | grep "Creation Date"

What to do if your domain is too new:

Best practice: Use a domain that's 60+ days old for cold outreach.

Test your domain setup → checkyouremail.online

☐ 2. SPF Record Is Configured Correctly

Why it matters: Without SPF, receiving servers can't verify you're authorized to send from this domain.

How to check: 

nslookup -type=TXT yourdomain.com

Look for a record starting with v=spf1.

What the record should look like:

If sending from Google Workspace: 

v=spf1 include:_spf.google.com -all

If sending from your own server: 

v=spf1 ip4:203.0.113.10 -all

If using multiple services: 

v=spf1 include:_spf.google.com include:sendgrid.net -all

What to fix:

☐ 3. DKIM Signing Is Enabled

Why it matters: DKIM proves your emails haven't been tampered with and actually came from your domain.

How to check:

Send yourself a test email. View full headers. Look for: 

DKIM-Signature: v=1; a=rsa-sha256; d=yourdomain.com

And in authentication results: 

dkim=pass

What to fix:

For Google Workspace: 1. Admin Console → Apps → Gmail → Authenticate email 2. Generate new record 3. Add TXT record to DNS at google._domainkey.yourdomain.com

For other providers, follow their DKIM setup documentation.

☐ 4. DMARC Policy Is Set (Minimum p=none)

Why it matters: DMARC ties SPF and DKIM together. Gmail and Yahoo require it for bulk senders.

How to check: 

nslookup -type=TXT _dmarc.yourdomain.com

What the record should look like:

Start with monitoring: 

v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com

After 2 weeks of clean reports: 

v=DMARC1; p=quarantine; rua=mailto:dmarc@yourdomain.com; pct=100

What to fix:

Test authentication → checkyouremail.online

☐ 5. Domain Warmup Is Complete (If Domain Is New)

Why it matters: Sending high volume immediately from a new domain gets you spam filtered.

Warmup schedule:

During warmup:

What to fix:

☐ 6. Your Domain Isn't on Any Blacklists

Why it matters: Blacklisted domains get automatically filtered to spam or rejected entirely.

How to check:

Major blacklists to monitor:

Or use comprehensive checkers like checkyouremail.online.

What to fix:

List Quality and Targeting

☐ 7. You're Not Using Purchased or Scraped Lists

Why it matters: Bought lists contain spam traps and unengaged recipients. You'll get blacklisted within days.

What qualifies as a good list:

What to avoid:

What to fix:

☐ 8. Email Addresses Are Verified

Why it matters: High bounce rates (20%+) signal poor list hygiene and tank your sender reputation.

How to verify:

Use email verification tools:

What they check:

What to fix:

☐ 9. Removed Role Addresses and Catch-Alls

Why it matters: Role addresses (info@, support@) and catch-all addresses rarely engage and often mark as spam.

What to remove:

Role addresses:

Why they're problematic:

What to keep:

What to fix:

☐ 10. Personalization Goes Beyond First Name

Why it matters: {{FirstName}} personalization fools no one. Real personalization improves response and reduces spam reports.

Weak personalization: 

Hi {{FirstName}},
I noticed your company needs help with email deliverability...

Strong personalization: 

Hi John,
I saw TechCorp recently launched the new customer portal. 
Quick question about how you're handling email notifications 
for the 10,000+ daily active users...

Variables to use:

What to fix:

Check your email content → checkyouremail.online

Email Content and Structure

☐ 11. Subject Line Is Under 50 Characters and Not Salesy

Why it matters: Subject lines affect both open rates and spam filtering.

Bad subject lines:

Good subject lines:

Best practices:

What to fix:

☐ 12. Email Body Is 50-150 Words

Why it matters: Long emails get ignored. Short emails get read and have higher response rates.

Ideal cold email length: 50-150 words

Structure: 1. Personal greeting (Hi John,) 2. Reason for reaching out (1 sentence) 3. Brief value proposition (2-3 sentences) 4. Simple ask (1 sentence) 5. Sign-off

Example (118 words):

Hi John,
I saw TechCorp launched the new customer portal last week—congrats on that.
Quick question: How are you handling email deliverability for the password 
reset and notification emails? We work with SaaS companies at your scale and 
noticed a common issue where transactional emails hit spam during high-volume 
periods.
We built a tool that specifically solves this for customer portal notifications. 
Would it make sense to show you how it works? I can record a 3-minute video 
for your team.
Let me know if you're interested.
Best,
Sarah

What to fix:

☐ 13. Text-to-Image Ratio Above 80/20

Why it matters: Image-heavy emails look like marketing and get filtered.

For cold email:

What to fix:

☐ 14. 2 or Fewer Links Per Email

Why it matters: Multiple links signal marketing content and reduce trust.

Link best practices:

What to fix:

Test your email content → checkyouremail.online

☐ 15. Sender Address and Reply-To Match

Why it matters: Mismatched addresses look suspicious and hurt deliverability.

Correct setup:

Incorrect setup:

What to fix:

Sending Behavior and Volume

☐ 16. Starting Volume Is 50 Emails/Day or Less

Why it matters: Volume spikes trigger spam filters. Start small and ramp gradually.

Recommended ramp:

New domain/new sending:

Established domain:

What to fix:

☐ 17. Consistent Daily Sending (No Large Gaps)

Why it matters: Inconsistent sending patterns look suspicious. Daily consistency builds reputation.

Good pattern:

Bad pattern:

What to fix:

Monitoring and Engagement

☐ Bonus: Engagement Monitoring Is Set Up

Why it matters: You need to see what's working and catch issues early.

What to monitor:

Delivery metrics:

Engagement metrics:

Reputation metrics:

What to fix:

Test your complete setup → checkyouremail.online

Red Flags That Mean Don't Send Yet

Stop and fix these issues before sending:

🚩 Sender Score below 70 Your reputation is damaged. Rebuild before cold outreach.

🚩 Bounce rate above 10% on test sends Your list quality is terrible. Verify emails first.

🚩 Domain registered less than 30 days ago Wait. Age your domain with regular use.

🚩 No SPF, DKIM, or DMARC Set up authentication first. This is non-negotiable.

🚩 You're on any major blacklist Get delisted and fix the cause before sending.

🚩 You bought the email list Delete it. Build a proper targeted list.

🚩 Planning to send 1,000+ emails on day 1 Start with 50/day and ramp gradually.

The Pre-Send Test Protocol

Before launching any cold email campaign:

Day -7:

Day -3:

Day -1:

Day 1:

Week 1:

Week 2+:

When to Stop and Reassess

Pause your campaign immediately if:

Fix the issue before resuming. Continuing to send when metrics are bad only makes things worse.

The Complete Pre-Launch Checklist

Domain & Authentication:

List Quality:

Email Content:

Sending Behavior:

Cold email deliverability isn't luck. It's process. Check every item on this list before sending, and your emails will reach the inbox.

Run a free deliverability check right now at checkyouremail.online — no signup, results in 30 seconds.