10 Best Practices for Improving Email Deliverability

Email deliverability is the foundation of any successful email strategy. Without it, your carefully crafted messages never reach your audience. Here are 10 proven practices to maximize your inbox placement.

1. Authenticate Your Domain

Email authentication is non-negotiable. Implement these three protocols:

SPF (Sender Policy Framework) tells receiving servers which IP addresses are authorized to send email on behalf of your domain. Without SPF, your emails may be rejected outright.

DKIM (DomainKeys Identified Mail) adds a digital signature to your emails, proving they haven't been tampered with in transit. This builds trust with email providers.

DMARC (Domain-based Message Authentication, Reporting & Conformance) tells receiving servers what to do with emails that fail SPF or DKIM checks. Start with a "none" policy to monitor, then gradually move to "quarantine" and "reject" as you gain confidence.

2. Warm Up Your IP Address

If you're using a new dedicated IP, don't blast thousands of emails on day one. ISPs view sudden spikes in volume from unknown IPs as suspicious.

Start with 50-100 emails per day to your most engaged recipients. Gradually increase volume over 4-6 weeks. This builds a positive sending reputation.

3. Maintain a Clean Email List

Your list hygiene directly impacts deliverability. Remove these addresses immediately:

Hard bounces (invalid addresses)
Spam complainers
Unsubscribes
Addresses with no engagement for 6+ months

Consider using email verification services before importing new lists. A bounce rate above 2% signals problems to ISPs.

4. Monitor Your Sender Reputation

Your sender reputation is a score that ISPs use to determine whether to deliver your emails. Check your reputation regularly using:

Google Postmaster Tools (for Gmail)
Microsoft SNDS (for Outlook/Hotmail)
Third-party tools like SenderScore

Address any reputation issues immediately. A damaged reputation can take months to recover.

5. Use a Consistent "From" Name and Address

Recipients should instantly recognize who the email is from. Consistency builds trust and reduces spam complaints.

Use your brand name, not generic addresses like "noreply@"
Stick with the same "From" address across campaigns
Match your "From" domain to your website domain

6. Write Engaging Subject Lines

Subject lines that trigger spam filters often contain:

ALL CAPS words
Excessive punctuation (!!!, ???)
Spam trigger words ("Free!!!", "Act Now", "Limited Time")
Misleading claims

Instead, write clear, honest subject lines that match your email content. Personalization (using the recipient's name) can improve open rates.

7. Optimize Your Email Content

The content inside your emails matters for deliverability:

**Balance text and images**: Avoid image-only emails. Aim for a 60/40 text-to-image ratio.
**Include a plain text version**: Some email clients prefer plain text, and spam filters like seeing both versions.
**Test your links**: Broken links and links to suspicious domains hurt deliverability.
**Add an unsubscribe link**: It's legally required and reduces spam complaints.

8. Send at the Right Frequency

Finding the optimal sending frequency depends on your audience:

Too many emails → spam complaints and unsubscribes
Too few emails → subscribers forget they signed up, leading to complaints

Monitor engagement metrics to find your sweet spot. If open rates decline, you might be over-sending.

9. Segment Your Audience

Not every subscriber wants every email. Segment your list by:

Engagement level (highly engaged vs. dormant)
Interests or preferences
Purchase history
Sign-up source

Send relevant content to each segment. This improves engagement and reduces complaints.

10. Monitor and Iterate

Deliverability isn't a "set it and forget it" task. Continuously monitor:

Bounce rates by domain
Spam complaint rates
Open and click rates by ISP
Inbox placement rates

When metrics dip, investigate immediately. Small issues can snowball into major deliverability problems.

Conclusion

Email deliverability requires ongoing attention, but the fundamentals remain constant: authenticate your domain, maintain list hygiene, send relevant content, and monitor your metrics. Master these practices, and your emails will consistently reach the inbox.

At Postalynk, we provide built-in tools to help you implement all of these practices. From automatic bounce handling to real-time deliverability monitoring, we've got you covered.