I'm building an app that sends verification emails and need good deliverability

To improve verification email deliverability, focus on authentication, sender reputation, message quality, and sending behavior.

1) Use proper email authentication

Set up all three:

• SPF — authorizes your sending service/IP
• DKIM — cryptographically signs messages
• DMARC — tells inbox providers how to handle failures and gives you reports

Also make sure:

• Your From domain matches your authenticated domain
• You use a custom domain for sending, not a generic shared one if possible

2) Send from a reputable email provider

For verification emails, use a provider with strong deliverability infrastructure:

• SendGrid
• Postmark
• Amazon SES
• Mailgun
• Resend

If you’re early-stage, Postmark or Amazon SES are often strong choices for transactional mail.

3) Keep the content simple and consistent

Verification emails should be:

• Short and clearly transactional
• Plain text + lightweight HTML
• Free of spammy language like “FREE,” “ACT NOW,” excessive punctuation, etc.
• Branded consistently with your app domain and logo

Include:

• Clear subject line
• Single prominent verification button/link
• Fallback raw link
• Support/contact info
• No attachments

4) Use a dedicated sending subdomain

A common best practice:

• Main site: example.com
• Email sending: mail.example.com or auth.example.com

This helps isolate reputation and simplifies DNS setup.

5) Protect your reputation

Verification traffic should be clean, but still:

• Rate-limit signups and verification sends
• Prevent bot abuse and email bombing
• Don’t resend too aggressively
• Remove hard bounces and invalid addresses immediately
• Handle complaints/unsubscribes if you ever send more than transactional mail

6) Make sure users can find it

To improve engagement signals:

• Send immediately after signup
• Make the “Verify your email” CTA obvious
• Avoid delays of more than a few minutes
• Resend only on request

7) Monitor deliverability

Track:

• Bounce rate
• Spam complaint rate
• Open/click rates
• Inbox placement if your provider offers it

Use tools like:

• Google Postmaster Tools
• Microsoft SNDS
• DMARC reports
• Mail-tester.com for test messages

8) Technical best practices

• Use a stable From name and From email
• Set Reply-To only if needed
• Ensure your links use HTTPS
• Avoid URL shorteners
• Use consistent sending IPs if on dedicated infrastructure
• Warm up new domains/IPs gradually

Good default setup

If you want a strong starting point:

1. Register auth.yourdomain.com
2. Configure SPF, DKIM, DMARC
3. Use Postmark or SES
4. Send short transactional verification emails only
5. Monitor bounces and complaints
6. Gradually increase volume if needed

If you want, I can also give you:

• a DNS record checklist for SPF/DKIM/DMARC,
• a recommended email template for verification,
• or a deliverability setup for a specific provider like SES, SendGrid, or Postmark.