Deliverability is the silent killer of cold outreach. You can write the most compelling email in the world, but if it lands in spam — or worse, gets silently dropped — nothing else matters. Most senders don’t discover the problem until their open rates collapse.
Here’s what to check before your first send.
1. SPF Record
Your SPF record tells receiving mail servers which IPs are allowed to send on behalf of your domain. A missing or broken SPF record is the fastest way to get flagged.
Check it: Run nslookup -type=TXT yourdomain.com or use MXToolbox. You should see a record starting with v=spf1.
What you want: Something like v=spf1 include:_spf.google.com ~all for Google Workspace.
2. DKIM Signature
DKIM adds a cryptographic signature to outgoing emails. Receiving servers use the public key in your DNS to verify the message wasn’t tampered with in transit.
Check it: Send a test email to mail-tester.com and review the DKIM result. It should show a pass with your domain’s selector.
Common mistake: Using the default selector (google) instead of a custom one. Not a dealbreaker, but a custom selector gives you better control.
3. DMARC Policy
DMARC tells receiving servers what to do when SPF and DKIM checks fail. Without it, anyone can spoof your domain, and some receiving servers will treat your legitimate emails with extra suspicion.
Start with: v=DMARC1; p=none; rua=mailto:[email protected]
The p=none policy means no action is taken on failures — you just get reports. Move to p=quarantine or p=reject once you’ve confirmed your legitimate mail is passing.
4. Domain Age and Warmup
New domains have no sending reputation. Sending 500 emails on day one will get you blocked almost immediately.
Warmup schedule: Start with 20 emails per day per account in week one, 50 in week two, 100 in week three. After 4-6 weeks of consistent, engaged sending, you can approach normal volume.
Tools: Use a dedicated warmup tool or do it manually by sending to addresses you control that will open and reply.
5. Sending Account Ratio
The cold outreach industry standard is 30-50 emails per account per day after warmup. More than that and you’re burning reputation you’ve spent weeks building.
If you need to send 500 emails/day, you need 10-15 Google Workspace accounts. This is a real infrastructure cost — factor it into your planning.
6. Plain Text vs HTML
Heavy HTML templates with images and complex formatting are a major spam signal. Cold emails should look like they were written by a human, not designed in Mailchimp.
Best practice: Plain text or minimal inline styles. One CTA. No images in the first sequence step.
7. Unsubscribe Mechanism
You’re legally required to offer an unsubscribe option (CAN-SPAM, GDPR). A simple line like “Reply STOP to unsubscribe” at the bottom of your email keeps you compliant without hurting deliverability.
8. Bounce Rate
If your bounce rate exceeds 2-3%, your sending reputation will crater quickly. Validate email addresses before sending using tools like Hunter.io or ZeroBounce.
PitchGale handles this automatically — lead enrichment includes email verification before any contact enters a campaign.
9. Spam Trigger Words
Words like “free”, “guaranteed”, “no cost”, “act now”, “limited time” in subject lines are reliable spam triggers. Keep subject lines curious and conversational, not promotional.
Test before sending: Use mail-tester.com to score your email. Aim for 9+/10.
10. Reply-to Address
Your reply-to address should be real and actively monitored. If recipients reply and you don’t respond, it hurts your domain reputation over time (positive signals from replies are one of the strongest deliverability factors).
Deliverability isn’t a one-time setup — it’s an ongoing practice. Check these items before every new campaign domain and review your sending reputation monthly using Google Postmaster Tools.
PitchGale’s deliverability assistant automates most of this: DNS verification, warmup guidance, and real-time bounce monitoring are built into the dashboard.