🔐 Authentication

What is DMARC?
Complete Setup Guide

📅 Updated March 2026⏱ 6 min read📋 Beginner-Friendly

DMARC (Domain-based Message Authentication, Reporting & Conformance) ties your SPF and DKIM together and tells receiving mail servers what to do when authentication fails. It's the final piece of the email authentication puzzle.

⚠️Required since 2024: Gmail and Yahoo now require DMARC for all senders sending over 5,000 emails per day. Even lighter senders benefit from better deliverability.

How DMARC Works

When someone receives an email claiming to be from your domain, their mail server:

  1. Checks if the email passes SPF (is it from an authorized server?)
  2. Checks if the email passes DKIM (is the signature valid?)
  3. Looks up your DMARC record to see what to do if either fails
  4. Optionally sends you a report about the authentication result
📋SPFWho can send
🔑DKIMSignature verification
🛡️DMARCPolicy + reporting

DMARC Policies Explained

The p= tag in your DMARC record tells receiving servers what to do with emails that fail authentication:

p=none— Monitor Only

Don't change delivery, just send reports. Start here to see what's happening.

p=quarantine— Send to Spam

Failed emails go to spam folder. Good middle ground after monitoring.

p=reject— Block Completely

Failed emails are rejected entirely. Maximum protection against spoofing.

How to Set Up DMARC

DMARC is a DNS TXT record. Here's how to add it:

  1. 1
    Make sure SPF and DKIM are workingDMARC depends on these. Test at CheckEmailDelivery.com first.
  2. 2
    Go to your DNS providerCloudflare, GoDaddy, Namecheap, Route53, etc.
  3. 3
    Add a new TXT record
    Record Name_dmarc
    Record Value (Start Here)v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com
  4. 4
    Wait and review reportsAfter 2–4 weeks of monitoring, upgrade to p=quarantine, then p=reject.

Example DMARC Records

Basic (Monitoring Only)
v=DMARC1; p=none; rua=mailto:dmarc@example.com
Intermediate (Quarantine)
v=DMARC1; p=quarantine; pct=100; rua=mailto:dmarc@example.com
Strict (Full Protection)
v=DMARC1; p=reject; pct=100; rua=mailto:dmarc@example.com; ruf=mailto:forensics@example.com
🎯Test your DMARC: Run a free email test at CheckEmailDelivery.com to verify your DMARC record is set up correctly.

Related Guides

AUTHENTICATIONSPF Record Setup GuideAUTHENTICATIONHow to Fix DKIMDELIVERABILITYWhy Emails Go to Spam