Email deliverability is the single most important factor in cold email performance. You can have the best prospect list and the most compelling messaging in the world, but if your emails land in spam, none of it matters. Instantly provides several tools and features that help you maintain strong deliverability, but using them effectively requires understanding what drives deliverability in the first place.
The Factors That Affect Deliverability
Email deliverability is determined by several factors including your sender reputation, your domain age, your email authentication setup, your sending volume and patterns, your email content, and your engagement rates. Each of these factors sends signals to internet service providers about whether your emails are legitimate and wanted by recipients.
Email Authentication
The foundation of good deliverability is proper email authentication. Every sending domain must have SPF, DKIM, and DMARC records configured correctly. SPF tells receiving mail servers which servers are authorized to send email from your domain. DKIM adds a cryptographic signature to your emails that verifies they have not been tampered with. DMARC tells receiving servers what to do with emails that fail SPF or DKIM checks. Set these up correctly before sending a single cold email.
Sending Volume and Patterns
Send conservatively and consistently. Sudden spikes in sending volume are a major red flag for spam filters. Start with low daily sending limits and increase them gradually over several weeks. Maintain consistent sending patterns rather than sending in bursts. Instantly’s sending schedule settings allow you to control exactly when and how many emails are sent each day.
Content and Engagement
Email content affects deliverability in ways that many senders underestimate. Avoid spam trigger words, excessive links, and large images in your cold emails. Keep your emails plain text or minimal HTML. High engagement rates including opens and replies signal to internet service providers that your emails are wanted, which improves your deliverability over time. Low engagement and high unsubscribe rates have the opposite effect.
