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Using DMARC with Sendamatic

Configure a custom MAIL FROM domain in your mail identity, and mail sent through Sendamatic will be compatible with your DMARC policy.

Securing email Delivery with DMARC (Domain-based Message Authentication, Reporting & Conformance)

Email remains the most ubiquitous forms of business communication, but its open architecture unfortunately leaves it vulnerable to security threats like phishing and spoofing. An important email authentication system called DMARC aims to address some of these vulnerabilities and prevent cybercriminals from impersonating legitimate senders.

What Does DMARC Do?

DMARC stands for Domain-based Message Authentication, Reporting & Conformance. It’s an email authentication standard that’s designed to give email recipients more control over messages sent from a specific domain while also giving senders visibility into misuse of their domain.

At its core, DMARC helps receiving email providers determine if incoming messages are truly from who they claim to be from. It allows a domain owner to implement a policy that dictates what should happen to messages not passing authentication checks. For instance, mail deemed illegitimate could be rejected or sent to spam. Valid messages are delivered per normal.

How DMARC authentication works

DMARC works hand-in-hand with two other email security systems - SPF and DKIM - to authenticate messages. When an email comes in claiming to be from a certain domain, DMARC checks to see if it:

  • Originated from an IP address sanctioned to send mail from that domain according to its SPF record.
  • Has been digitally signed using DKIM in line with published DNS records.

If both these authentication checks pass, DMARC knows the message legitimately came from the purported domain. If either fails, it’s likely an impersonation attempt.

DMARC reporting and benefits

In addition providing authentication mechanisms, DMARC also defines user-controlled policies and facilitates aggregate and forensic reporting about email traffic for a domain. This visibility allows senders to identify unauthorized use of their domain as well as to monitor legitimate deliverability.

When implemented properly, DMARC prevents bad actors from distributing malicious emails disguised as trusted brands. Email receivers can have higher confidence in messages originating from DMARC compliant domains. This leads to improved email deliverability and more positive engagement with email campaigns.

As more senders publish strict DMARC policies and more receivers honor reject signals, the email ecosystem grows safer against abuse. Implementing DMARC remains an essential best practice for email security and authentication.

Further reading

Free DMARC monitoring from Postmark