SPF and DMARC explained for marketers

What is SPF?

SPF (Sender Policy Framework) is a DNS record that lists which mail servers are allowed to send email on behalf of your domain. When you send an email, the recipient's server checks whether your sending IP is in the SPF record. If it isn't, the email may be marked as spam or rejected.

What is DMARC?

DMARC (Domain-based Message Authentication, Reporting, and Conformance) builds on SPF and DKIM. It tells receiving servers what to do when an email fails authentication — reject it, quarantine it (send to spam), or do nothing. It also enables reporting so you can see who is sending email using your domain.

Why they matter for email validation

When you're validating a list, domains without SPF or DMARC records are a signal of lower legitimacy. A business domain with no email authentication configured is more likely to be:

• A newly registered domain with no real operations
• A parked or abandoned domain
• A domain used for spam or phishing

BounceProtect checks SPF and DMARC for every domain and factors them into the spam risk score and send recommendation.

How to check SPF and DMARC

You can look up any domain's SPF record with: nslookup -type=txt yourdomain.com

And DMARC with: nslookup -type=txt _dmarc.yourdomain.com

Or use BounceProtect's Deep Analysis feature to see SPF, DMARC, SSL, domain age, and business legitimacy score in one view.

What to do if a domain has no SPF or DMARC

For your own domain: set up SPF and DMARC records immediately. Most ESPs provide step-by-step instructions. Without them, your emails are more likely to land in spam.

For addresses on your list: emails from domains with no SPF or DMARC are flagged by BounceProtect as "Risky" — they may still deliver, but they carry higher spam risk.