How does DMARC impact email deliverability, and what are the pros and cons of using it?

Summary

DMARC (Domain-based Message Authentication, Reporting & Conformance) significantly impacts email deliverability by providing a framework for authenticating email and protecting domains from unauthorized use such as spoofing and phishing. It relies on SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail) and allows domain owners to specify how recipient mail systems should handle messages that fail authentication. While DMARC is not directly a deliverability protocol, successful implementation can improve inbox placement, protect brand reputation, and increase ROI for email marketing efforts. Key benefits include enhanced visibility into email streams, protection against phishing attacks, and improved brand reputation. However, DMARC implementation can be challenging, requiring a careful understanding of reporting, proper authentication of all legitimate sending sources, and a phased deployment approach. A poorly configured DMARC policy, especially a 'reject' policy, can inadvertently block legitimate email. DMARC reporting provides valuable insights into an organization's email ecosystem, enabling identification and resolution of deliverability issues.

Key findings

  • Enhanced Deliverability: DMARC improves email deliverability by signaling to email providers that emails are legitimate, increasing inbox placement.
  • Brand and Customer Protection: DMARC protects domains and customers from unauthorized use, such as spoofing and phishing attacks.
  • Visibility and Control: DMARC provides domain owners increased visibility into email streams and control over how unauthenticated mail is handled.
  • Positive Authentication Signal: DMARC-aligned DKIM and SPF are positive signals for deliverability.
  • Impact on ROI: Implementing DMARC can increase the ROI of email marketing campaigns by ensuring emails reach the inbox.

Key considerations

  • Implementation Complexity: Setting up DMARC can be challenging, especially understanding and interpreting DMARC reports.
  • Risk of Blocking Legitimate Email: A 'p=reject' policy can block legitimate emails if not implemented and monitored carefully.
  • Phased Deployment Recommended: It's essential to deploy DMARC in stages (p=none, p=quarantine, p=reject) to avoid unintended consequences.
  • Continuous Monitoring: Continuous monitoring of DMARC reports is crucial for identifying and addressing deliverability issues.
  • DMARC is Not Anti-Spam: DMARC is primarily an authentication tool, not an anti-spam tool, although it contributes to a healthier email ecosystem.

What email marketers say
11Marketer opinions

DMARC (Domain-based Message Authentication, Reporting & Conformance) impacts email deliverability primarily by helping mailbox providers identify legitimate email senders and protecting against unauthorized use of a domain, like spoofing and phishing. While DMARC itself isn't a deliverability protocol, it enhances deliverability by improving inbox placement and brand reputation. Implementing DMARC involves setting policies that tell recipient systems how to handle emails failing authentication (SPF and DKIM). The benefits include increased visibility into email streams, protection against phishing attacks, and improved brand reputation, leading to a higher ROI for email marketing. However, DMARC implementation can be challenging, requiring careful monitoring of reports and proper authentication of all legitimate sending sources. A 'p=reject' policy, if not carefully managed, can block legitimate emails. Gradual deployment, starting with 'p=none' for monitoring, is recommended.

Key opinions

  • Deliverability Enhancement: DMARC enhances email deliverability by helping mailbox providers identify legitimate senders, reducing the chances of emails being marked as spam.
  • Brand Protection: Implementing DMARC protects against unauthorized use of a domain, safeguarding brand reputation and customer trust.
  • Anti-Fraud Mechanism: DMARC serves as an anti-fraud protocol, protecting against phishing and spoofing attacks.
  • Visibility into Email Streams: DMARC provides increased visibility into who is sending emails on behalf of a domain, enabling the identification of unauthorized sending sources.
  • ROI Improvement: Implementing DMARC can increase the ROI of email marketing campaigns by ensuring emails reach the inbox.

Key considerations

  • Implementation Challenges: Setting up DMARC can be challenging, requiring careful understanding of reporting and data interpretation.
  • Policy Impact: A 'p=reject' policy can block legitimate emails if not implemented carefully, necessitating proper authentication of all sending sources.
  • Gradual Deployment: It is recommended to deploy DMARC gradually, starting with 'p=none' to monitor email traffic before moving to more restrictive policies.
  • Monitoring is Key: Continuous monitoring of DMARC reports is essential for identifying and addressing deliverability issues.
  • Not Anti-Spam: DMARC is primarily an authentication tool, not an anti-spam tool, though it contributes to better email ecosystem health.
Marketer view

Email marketer from Email Marketing Forum explains a potential con of a DMARC reject policy. If you have legitimate email sources that aren't properly authenticated, a 'p=reject' policy could cause those emails to be blocked, impacting legitimate communications.

June 2023 - Email Marketing Forum
Marketer view

Email marketer from Litmus explains that DMARC is a key component of email deliverability best practices. They recommend starting with a policy of 'p=none' to monitor your email traffic before moving to more restrictive policies like 'p=quarantine' or 'p=reject'.

October 2024 - Litmus
Marketer view

Email marketer from Mailjet shares that DMARC helps mailbox providers identify legitimate email from your domain, improving inbox placement. Implementing DMARC correctly can significantly reduce the chances of your emails being marked as spam.

October 2022 - Mailjet
Marketer view

Marketer from Email Geeks shares that there is not currently a harsh punishment for not participating in DMARC. DMARC is not a deliverability protocol but an anti-fraud protocol for large brands which offers benefits like BIMI eligibility.

December 2023 - Email Geeks
Marketer view

Email marketer from Reddit explains that setting up DMARC can be challenging, especially understanding the reporting and interpreting the data. They share that many organizations struggle with monitoring DMARC reports and identifying legitimate sending sources.

February 2022 - Reddit
Marketer view

Email marketer from SparkPost shares that implementing DMARC provides increased visibility into who is sending email on behalf of your domain, allowing you to identify and prevent unauthorized sending. It also protects recipients from phishing attacks and improves brand reputation.

November 2022 - SparkPost
Marketer view

Email marketer from Email on Acid shares that by implementing DMARC and protecting your domain from abuse, you can increase the ROI of your email marketing campaigns. Ensuring that your emails reach the inbox is crucial for generating leads, driving sales, and building customer loyalty.

February 2025 - Email on Acid
Marketer view

Email marketer from Sendinblue shares that DMARC can significantly improve your brand reputation by protecting recipients from email scams such as phishing. By implementing DMARC you can build trust with your customers, which increases the chances of your emails reaching the inbox.

December 2022 - Sendinblue
Marketer view

Email marketer from Postmark shares the importance of carefully deploying DMARC in stages, starting with 'p=none', then 'p=quarantine', and finally 'p=reject' to avoid unintended consequences. Monitor DMARC reports throughout the deployment process.

December 2021 - Postmark
Marketer view

Email marketer from Quora shares that even small businesses should implement DMARC to protect their brand and customers from email fraud. Even if they don't send many marketing emails, DMARC can prevent scammers from spoofing their domain for phishing attacks.

August 2023 - Quora
Marketer view

Marketer from Email Geeks explains that p= is just a suggestion to the receiver, and they can do what they want with it, but most receivers follow the suggestion. SPF/DKIM/DMARC are authentication tools, not anti-spam tools, though they do help.

January 2025 - Email Geeks

What the experts say
5Expert opinions

Experts highlight that DMARC impacts email deliverability by providing a framework for email authentication and policy enforcement. DMARC-aligned DKIM and SPF serve as positive signals for deliverability. Enforcing DMARC records primarily affect non-authenticated emails, potentially damaging their deliverability, while authenticated emails are less impacted. DMARC allows domain owners to specify how recipient systems handle emails failing authentication, reducing phishing and spoofing. However, the deliverability benefits of BIMI (which requires DMARC) are still under discussion, with no definitive data. DMARC provides domain owners increased visibility into email streams, further allowing them to dictate the handling of unauthenticated mail, aiding in protecting brand reputation and improving deliverability.

Key opinions

  • Positive Signal: DMARC-aligned DKIM and SPF serve as positive signals for deliverability.
  • Impact on Authenticated Emails: Enforcing DMARC primarily impacts non-authenticated emails, potentially damaging their deliverability. Authenticated emails are less affected.
  • Phishing and Spoofing Protection: DMARC allows domain owners to specify how recipient systems handle emails failing authentication, reducing phishing and spoofing.
  • Visibility and Control: DMARC provides domain owners increased visibility into email streams and allows them to dictate the handling of unauthenticated mail.
  • BIMI Benefit Uncertain: The deliverability benefits of BIMI (which requires DMARC) are still under discussion, with no definitive data.

Key considerations

  • Authentication is Key: Ensure all legitimate email sources are properly authenticated to avoid deliverability issues when enforcing DMARC policies.
  • Monitor DMARC Records: Regularly monitor DMARC reports to identify and address any authentication failures or potential issues.
  • Gradual Rollout: Consider a gradual rollout of DMARC policies to avoid unintended consequences on legitimate email traffic.
  • DMARC as Part of a Strategy: Understand that DMARC is part of a broader email authentication and deliverability strategy, including SPF and DKIM.
Expert view

Expert from Word to the Wise shares that DMARC provides increased visibility into email streams and allows domain owners to specify how mailbox providers should handle unauthenticated mail, helping improve deliverability and protect their brand reputation.

April 2021 - Word to the Wise
Expert view

Expert from Email Geeks explains that publishing an enforcing DMARC record probably won't affect deliverability much for authenticated emails, but will damage deliverability for non-authenticated emails. Filters may use the presence of a DMARC record as one of many data points.

October 2021 - Email Geeks
Expert view

Expert from Spam Resource explains that DMARC allows the domain owner to publish a policy that tells recipient systems how to handle messages that fail authentication checks, reducing successful phishing attacks and helping to prevent domain name spoofing.

March 2021 - Spam Resource
Expert view

Expert from Email Geeks notes there's a discussion about whether BIMI, which requires DMARC, benefits deliverability, but there's no current data to suggest it does.

September 2024 - Email Geeks
Expert view

Expert from Email Geeks explains that having DMARC-aligned DKIM and/or SPF authentication is a positive signal for deliverability.

March 2023 - Email Geeks

What the documentation says
5Technical articles

The documentation consistently states that DMARC enhances email deliverability by protecting domains from unauthorized use like spoofing and phishing attacks. It works by allowing senders to indicate that their emails are protected by SPF and DKIM, instructing receivers on how to handle unauthenticated messages. DMARC provides a framework for email authentication policies and reporting, helping email receivers distinguish legitimate senders from spoofed ones. Analyzing DMARC reports offers valuable insights into email ecosystems, aiding in identifying and addressing deliverability issues.

Key findings

  • Protection Against Unauthorized Use: DMARC protects domains from spoofing and phishing attacks.
  • Improved Deliverability: DMARC improves deliverability by signaling legitimacy to email providers.
  • Authentication Indication: DMARC lets senders indicate their emails are protected by SPF and DKIM.
  • Receiver Instructions: DMARC instructs receivers on handling unauthenticated messages.
  • Enhanced Ecosystem Insights: DMARC reporting provides insights into email ecosystems and identifies deliverability issues.

Key considerations

  • SPF and DKIM Dependence: DMARC builds upon SPF and DKIM, requiring proper setup of these protocols.
  • Reporting Analysis: Analyzing DMARC reports is essential for identifying and addressing issues.
  • Policy Enforcement: Organizations must define appropriate DMARC policies to handle unauthenticated emails effectively.
Technical article

Documentation from DMARC.org explains that DMARC helps protect your domain from unauthorized use, such as spoofing and phishing attacks. It also improves deliverability by signaling to email providers that your emails are legitimate.

February 2023 - DMARC.org
Technical article

Documentation from Microsoft explains that DMARC helps Office 365 customers protect themselves from phishing and spoofing attacks. By implementing DMARC, organizations can specify how Office 365 should handle emails that fail authentication checks.

September 2024 - Microsoft
Technical article

Documentation from ReturnPath explains that DMARC reporting provides valuable insights into your email ecosystem, including information about sending sources, authentication results, and potential spoofing activity. Analyzing DMARC reports helps identify and address deliverability issues.

April 2023 - ReturnPath
Technical article

Documentation from RFC Editor (RFC 7489) details the DMARC specification, explaining how DMARC builds upon SPF and DKIM to provide a framework for email authentication policies and reporting, helping email receivers handle unauthenticated email messages.

May 2022 - RFC Editor
Technical article

Documentation from Google Workspace Admin Help explains that DMARC lets senders indicate that their emails are protected by SPF and/or DKIM, and tells receivers what to do if neither of those authentication methods passes – such as junk or reject the message. DMARC helps receivers know that the sender is legitimate, and that the message they received isn't spoofed.

April 2024 - Google Workspace Admin Help