How to Improve Your Email Deliverability Score in 2026

If your emails land in spam, bounce, or vanish entirely, your email deliverability score is the problem. This single number determines whether your messages reach inboxes — and fixing it is simpler than you think.

In this guide, you'll learn exactly what affects your score, how to fix each problem, and how to monitor your deliverability going forward. Let's fix your email.

📊 What Is an Email Deliverability Score?

Your deliverability score is a composite rating (typically 0-100) that measures how likely your domain's emails are to reach inboxes rather than spam folders. It's calculated from:

• DNS Authentication — SPF, DKIM, and DMARC records (50 points)
• Mail Server Configuration — MX records with proper priorities (30 points)
• Blacklist Status — Whether your IPs appear on spam blocklists (-15 per listing)
• Content Quality — Spam trigger words, link ratios, header formatting

🔧 Step 1: Set Up SPF (Sender Policy Framework)

SPF tells receiving servers which IPs are allowed to send email for your domain. Without it, anyone can spoof your domain — and spam filters know it.

How to fix it: Add a TXT record to your DNS with this format:

Replace _spf.google.com with your email provider's SPF include. Common providers:

• Google Workspace: include:_spf.google.com
• Microsoft 365: include:spf.protection.outlook.com
• ProtonMail: include:_spf.protonmail.ch
• SendGrid: include:sendgrid.net

🔐 Step 2: Enable DKIM Signing

DKIM adds a cryptographic signature to every outgoing email. The receiving server verifies this signature against a public key in your DNS. It proves the email wasn't tampered with in transit.

How to fix it: Your email provider generates a DKIM key pair. They keep the private key; you publish the public key as a DNS TXT record under:

The selector (e.g., "google") varies by provider. Check your admin panel for exact values.

🛡️ Step 3: Deploy DMARC

DMARC combines SPF and DKIM and adds a policy: what should receiving servers do when authentication fails? It also gives you weekly reports showing who's sending email from your domain.

How to fix it: Start with monitoring mode:

After monitoring for 1-2 weeks, tighten the policy:

• p=quarantine — suspicious emails go to spam
• p=reject — suspicious emails are blocked entirely

Use our free DMARC record generator to create the correct record instantly.

📬 Step 4: Verify MX Records

MX records tell the world where your domain receives email. If they're missing or misconfigured, email simply won't arrive.

Common issues:

• Missing MX records entirely
• Pointing to a decommissioned mail server
• Wrong priority values (lower = higher priority)
• Using CNAME instead of proper A/AAAA for mail hosts

Check yours with our free DNS lookup tool — select MX record type.

🚫 Step 5: Check Blacklists

Even with perfect DNS setup, if your sending IP is on a spam blacklist, your email won't reach inboxes. The major blacklists to check:

• Spamhaus ZEN — the most widely used blocklist
• SpamCop — user-reported spam database
• Barracuda — enterprise email security
• SORBS — dynamic/spam source list

Use our free blacklist checker to scan your IPs against all major DNSBLs instantly.

If you're listed: Most blacklists have a removal/delisting form. Fix the underlying issue first (usually compromised accounts or misconfigured sending), then request removal.

✍️ Step 6: Optimize Email Content

Content triggers account for a significant portion of spam scoring. Avoid these common mistakes:

• ❌ ALL CAPS subject lines — reads as shouting
• ❌ Excessive punctuation — "!!!!!" or "???"
• ❌ Spam trigger words — "FREE!!!", "Act now!", "Limited offer!!!"
• ❌ Image-only emails — no text body means spam filters can't read content
• ❌ URL shorteners — common in phishing, use full URLs instead
• ❌ Missing text/plain version — always include a plain-text alternative

Run your email through our free spam score checker before sending to catch content issues.

📈 Step 7: Monitor Ongoing Health

Deliverability isn't "set and forget." DNS records expire, IPs get listed, and configurations drift. Set up monitoring:

• Domain expiry monitor — alerts before your domain expires
• SSL certificate reminders — 30/14/7 day renewal alerts
• DNS change detection — notified when records change
• Monthly PDF health reports — full audit with fix guide (€9)

❓ FAQ