Cold email outreach: master deliverability from A to Z
· Email · 7 min
Cold email outreach is one of the most scalable prospecting channels — but it’s also one of the most technical. An email that lands in spam is an entire campaign that disappears into thin air. Mastering deliverability is the sine qua non condition for your outreach to work.
1. Configure DNS records (SPF, DKIM, DMARC)
SPF (Sender Policy Framework) authorizes your server to send emails on behalf of your domain. DKIM (DomainKeys Identified Mail) adds a cryptographic signature to each email. DMARC defines the policy to apply if SPF and DKIM checks fail. These three records are non-negotiable to reach the primary inbox.
Practical tip: use a subdomain or a secondary domain for your cold emailing (e.g., outreach.yourcompany.com). This isolates the reputation of your main domain.
2. Warm-up: heat up your domain before sending
A new domain can’t send 200 emails per day on day one — spam filters will detect it immediately. Warm-up means gradually increasing your sending volume over 3 to 6 weeks. Tools like Lemwarm or Warmbox automate this process by simulating natural email exchanges.
3. List quality: reduce bounces
A bounce rate above 3% tells ISPs that you’re sending to invalid addresses — a sign of a purchased or poorly maintained list. Systematically verify your lists with email validation tools (NeverBounce, ZeroBounce) before any sending. The goal: a bounce rate below 2%.
4. Copywriting: avoid spam filters
Avoid classic spam triggers: uppercase words, too many links, images without text, and aggressive sales phrases ("exclusive offer", "click now", "free"). Write like a human talking to another human — a high-performing prospecting email looks like a real email, not a newsletter.
5. Tracking key metrics
Target open rate: above 40%. Target reply rate: above 8%. Bounce rate: below 2%. Unsubscribe rate: below 0.5%. If a campaign drops below these thresholds, pause and diagnose before continuing.
Measurable results: email outreach with our clients
Careful deliverability directly drives the results of an email campaign: without it, messages never reach the inbox.
Deliverability isn’t a setup you do once and forget — it’s an asset you maintain continuously. A well-configured domain, regular warm-up, a clean list, human copy: these four elements are the foundation of any profitable cold email campaign.