May 22nd, 2025
Email is one of the most powerful tools your organization uses, but it's also one of the most targeted by cybercriminals. If you're sending email from a custom domain and haven't implemented DMARC, your messages could be going to spam, or worse, used by attackers to impersonate your brand.
In this article, we'll break down what DMARC is, why it's now a requirement for reliable email delivery, and how your organization can get started quickly and securely.
What is DMARC?
DMARC (Domain-based Message Authentication, Reporting & Conformance) is an open email authentication protocol. It helps protect your domain from being spoofed or abused by verifying that only approved senders can send emails on your behalf.
DMARC works alongside:
- SPF (Sender Policy Framework): Verifies that emails come from approved servers.
- DKIM (DomainKeys Identified Mail): Uses cryptographic signatures to verify message integrity.
DMARC adds policy enforcement and visibility through reports, letting domain owners take control of their email ecosystem.
Why DMARC Matters More Than Ever
1. Required by Major Providers
Starting in 2024, major email services like Google (Gmail), Yahoo, and Microsoft require domains sending email—especially bulk messages, to have a valid DMARC policy.
Without DMARC, your email may:
- Be marked as spam
- Be rejected entirely
- Hurt your domain's sender reputation
2. Prevents Spoofing and Phishing
DMARC ensures that unauthorized senders can't forge your domain. This protects your customers, partners, and employees from email-based fraud.
3. Builds Trust and Brand Integrity
Every email you send reflects on your brand. DMARC ensures recipients can trust your messages, reinforcing professionalism and security.
4. Boosts Deliverability
Authenticated emails are more likely to land in the inbox. Without DMARC, even legitimate messages might not make it through.
5. Provides Critical Visibility
DMARC reports offer insights into who is sending email from, or pretending to send from, your domain. This helps detect abuse and uncover misconfigured systems.
How DMARC Works
- SPF and DKIM Setup: Configure these DNS records to authenticate your email sources.
- Publish a DMARC Record: Add a DMARC record to your DNS with a policy (
none,quarantine, orreject) and a reporting address. - Monitor Reports: Review DMARC XML reports to understand your domain's email traffic and sender behavior.
- Adjust Policy Over Time: Start with a monitoring policy (
p=none), then move toward enforcement (p=reject) as you validate sources.
Who Needs DMARC?
If your company sends transactional emails, newsletters, support responses, or any communication from a custom domain, you need DMARC.
Even if you rely on third-party services (like Google Workspace, Microsoft 365, Mailchimp, or SendGrid), DMARC ensures those messages are properly authenticated and trusted.
Getting Started
Step 1: Check Your Domain
Use tools like MXToolbox DMARC Checker or Google Postmaster Tools to see if your domain is protected.
Step 2: Set Up SPF & DKIM
Coordinate with your email provider or IT team to correctly configure these records.
Step 3: Add a DMARC Record
Start with a policy of p=none to monitor. Example:
v=DMARC1; p=none; rua=mailto:dmarc-reports@yourdomain.com;
Step 4: Monitor and Improve
Use a tool to analyze reports, identify unauthorized sources, and tighten your policy when you're confident.
Final Thoughts
DMARC is no longer optional—it's a requirement for secure, professional, and deliverable email. It protects your brand, improves your sender reputation, and ensures your messages reach their destination.
Don't wait until your domain is spoofed or your messages are undelivered. If you own a domain and send email, the time to implement DMARC is now.