DFY GTM Systems

Cold Email Deliverability Guide

By Abdul Sami, GTM Engineer · 8 min read · Last updated

Deliverability is decided by four inputs, roughly in this order: sender reputation (complaints, bounces, engagement), authentication (SPF/DKIM/DMARC), list quality, and content. Authentication is the entry ticket perfect records on a domain with 0.3% complaints still land in spam.

Reputation is the master variable

Mailbox providers score your domain and IPs on recipient behavior: spam complaints (keep under 0.1%), hard bounces (under 2%), and engagement (opens, replies). Complaints weigh heaviest 3 complaints per 1,000 sends can junk an entire domain.

The authentication floor

SPF, DKIM, and DMARC are table stakes since the 2024 Google/Yahoo bulk-sender rules. Missing or failing records are an automatic filter strike. Verify with the Email Deliverability Checker before any campaign.

List quality as deliverability

  • Verify every email before it enters a sequence.
  • Drop role accounts and catch-alls when volume is tight.
  • Never send to scraped, unverified lists one bad batch can burn a domain.

Content and engagement signals

Spam-trigger words matter less than they used to, but link-heavy, image-heavy, identical-blast emails still pattern-match to bulk mail. Plain-text-looking, varied (spintax), reply-inviting emails generate the engagement signals filters reward.

FAQ

Why are my cold emails going to spam?
Most often: new/unwarmed domain, high bounce or complaint rates, missing authentication, or identical high-volume content. Check in that order the Domain Health Checker covers the third instantly.
What is a good inbox placement rate?
90%+ on warmed, well-managed infrastructure. Below 80%, pause and diagnose before sending more more volume makes it worse, not better.
Do warm-up tools still work?
Yes for establishing baseline engagement history on new mailboxes. They're not a deliverability fix for burned domains only rest and root-cause fixes do that.
AS

Abdul Sami

GTM Engineer, DFY GTM Systems

7+ years building outbound systems for B2B companies across the US, UK, Australia, and DACH. Specializes in Clay workflows, cold email infrastructure, intent-based lead sourcing, and deliverability.

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