---
title: DMARC
description: Domain-based Message Authentication, Reporting and Conformance — email policy that tells receivers what to do when SPF/DKIM fail alignment.
url: https://www.factualminds.com/glossary/dmarc/
publishDate: 2026-07-22
updateDate: 2026-07-22
---

# DMARC

> Domain-based Message Authentication, Reporting and Conformance — email policy that tells receivers what to do when SPF/DKIM fail alignment.

## Definition

**DMARC** (Domain-based Message Authentication, Reporting and Conformance) is a DNS TXT policy on `_dmarc.example.com` that tells receiving mail systems what to do when a message claiming your domain fails **SPF** and/or **DKIM** alignment. Policies climb a ladder: `p=none` (monitor), `p=quarantine`, `p=reject`. Aggregate (`rua`) and forensic (`ruf`) reports help you find unauthorized senders before enforcement.

## When to use it

- Any domain that sends production email (transactional or marketing)
- Meeting Google/Yahoo/Microsoft **bulk-sender** minimums (at least `p=none` with working SPF+DKIM)
- As a prerequisite for **BIMI** (typically needs enforcement-level DMARC)

## When not to use it

- Jumping straight to `p=reject` before all legitimate senders (ESPs, CRMs, ticketing) are aligned — you will quarantine your own mail
- Publishing DMARC without collecting and reading `rua` reports for several weeks

## Tips

- Start at `p=none`, inventory failures, then raise `pct` and policy carefully
- Require **alignment** (organizational domain match) — SPF/DKIM “pass” alone is not enough for DMARC pass
- Prefer a dedicated reporting mailbox or SaaS parser; raw XML volume grows fast

## Gotchas

### Serious

- Multiple ESPs sending as `@brand.com` without DKIM/SPF alignment → enforcement blocks real campaigns
- Treating `p=none` as “done” forever while spoofing continues

### Regular

- Forgetting subdomains (`sp=` policy) used by legacy apps

## Related FactualMinds content

- [BIMI on Amazon SES](/blog/bimi-amazon-ses-implementation-guide/)
- [SPF](/glossary/spf/) · [DKIM](/glossary/dkim/) · [BIMI](/glossary/bimi/) · [Amazon SES](/glossary/amazon-ses/)

## Related AWS Services

- aws-ses
- aws-ses-migration

## Related Posts

- bimi-amazon-ses-implementation-guide
- amazon-ses-cold-email-b2b-compliance-deliverability-2026
- how-to-migrate-from-sendgrid-to-amazon-ses

---

*Source: https://www.factualminds.com/glossary/dmarc/*