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Regő Botond Ronyecz
Regő Botond Ronyecz

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DMARC Failed, SPF Passed: Why?

Teaser only. This is not the full article. Complete guide with alignment modes and envelope-from fixes: DMARC Alignment Failed, SPF Passed

DMARC Failed, SPF Passed: Why?

Your aggregate report shows spf=pass and dmarc=fail on the same row. That confuses teams who treat SPF as the whole job.

SPF authorizes an IP for the envelope-from domain (Return-Path). DMARC asks whether that domain aligns with the visible From: header. Mailchimp can pass SPF on sendgrid.net while your customer sees @yourcompany.com. SPF passes. DMARC fails.

Check alignment in headers:

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Fix the envelope-from, enable DKIM on your domain, or move marketing to a subdomain with its own policy.

In the full post on zerohook.org:

  • Strict vs. relaxed alignment (aspf= / adkim=)
  • HubSpot, SendGrid, and M365 alignment patterns
  • When to fix Return-Path vs. DKIM d=
  • Reading DMARC XML for alignment failures

Read the full guide: DMARC Alignment Failed, SPF Passed

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SealedMail •

The key concept here is identifier alignment. DMARC doesn't just need SPF to pass, it needs the domain in the SPF-authenticated MAIL FROM to match the header From: domain (in relaxed mode, the organisational domain). If your ESP uses their own return-path, SPF passes for them, not for you, so DMARC still fails despite the SPF result being green. DKIM is usually easier to align correctly with third-party senders.