DMARC (Domain-based Message Authentication, Reporting, and Conformance) plays a crucial role in email security and brand protection. While it does not directly guarantee inbox placement, its proper implementation significantly strengthens your sender reputation, which indirectly boosts deliverability. ESPs are increasingly encouraging, and in some cases requiring, senders to adopt DMARC policies due to new industry standards and the growing need to combat spoofing and phishing. The decision to implement DMARC should be a strategic one, carefully balancing potential deliverability impacts with the clear security benefits.
Key findings
Indirect deliverability impact: While DMARC doesn't directly improve deliverability, it enhances trust signals by allowing legitimate traffic to be distinguished from spoofed emails, which can positively influence inbox placement. Some mailbox providers factor DMARC into their reputation algorithms, even without an enforced policy.
Spoofing prevention: DMARC's primary benefit is preventing unauthorized use of your domain, protecting your brand from phishing and spoofing attacks. This ultimately safeguards your sender reputation.
Authentication standards: DMARC builds upon SPF and DKIM by providing a policy for unauthenticated messages and reporting mechanisms, which are becoming essential for high-volume senders, as highlighted by requirements from major mailbox providers.
BIMI enablement: A DMARC policy at quarantine or reject is a prerequisite for implementing BIMI (Brand Indicators for Message Identification), which displays your logo in the inbox, potentially increasing engagement.
Reporting value: DMARC reports offer invaluable insight into email flows, including legitimate and fraudulent sending, which is critical for monitoring your email ecosystem and troubleshooting DMARC failures.
Key considerations
Complexity of deployment: DMARC deployment can be complex and requires careful planning to avoid disrupting legitimate email streams. Misconfigurations can lead to significant deliverability issues.
Policy impact: A DMARC policy set to p=reject or p=quarantine can cause legitimate emails to be blocked or sent to spam if not properly aligned with SPF and DKIM.
Email forwarding: Email forwarding can break SPF authentication, leading to DMARC failures for legitimate emails. This requires careful consideration during implementation. More details on this can be found at Email on Acid.
Organizational decision: While ESPs should support alignment, the ultimate decision and responsibility for a DMARC policy rests with the sender's organization, as it affects all email flows from their domain.
Focus on fundamentals: Before pushing for DMARC, senders should ensure their basic deliverability practices are sound, such as list hygiene, content quality, and engagement. These often offer lower-hanging fruit for improving inbox placement.
Email marketers often approach DMARC from a pragmatic perspective, focusing on its direct impact on campaign performance and the balance between security benefits and potential implementation challenges. While acknowledging its importance for brand reputation and combating abuse, many marketers prioritize other deliverability factors first, especially for marketing-specific email flows.
Key opinions
Indirect benefit: Many marketers agree that DMARC does not directly improve deliverability, but rather addresses the trustworthiness of the brand and helps distinguish legitimate mail from spoofed attempts.
Preventing abuse: DMARC is seen as valuable if a domain is actively being abused, as it helps block fraudulent traffic and prevents reputation damage, ultimately benefiting the legitimate sender.
BIMI consideration: Some marketers acknowledge DMARC's role in enabling BIMI, which can increase engagement for specific B2C or webmail audiences, potentially leading to improved delivery rates.
Focus on fundamentals: There's a strong sentiment that more immediate deliverability improvements often come from addressing basic email hygiene, content quality, and engagement metrics, rather than purely technical authentication.
Key considerations
Risk of disruption: Marketers are wary that improperly implemented DMARC, especially with enforcement policies (p=quarantine or p=reject), can break existing mail flows and negatively impact deliverability, leading to legitimate emails being blocked or spam-foldered. This is a common concern among email marketers.
Complexity vs. perceived benefit: The perceived complexity of DMARC deployment, combined with the indirect nature of its deliverability benefits, can make it a lower priority for marketers compared to more direct campaign optimizations.
Alignment over policy: Some marketers advocate for ensuring SPF and DKIM alignment without necessarily publishing a strict DMARC policy, as some mailbox providers check alignment even in the absence of a DMARC record. This approach offers many of the benefits without the risks associated with an enforced policy. You can learn more about SPF, DKIM, and DMARC alignment here.
ESPs' role in guidance: Marketers look to ESPs for clear guidance and support on DMARC implementation, as well as alignment, rather than a forced setup that might break their email ecosystem. This is particularly relevant given recent requirements for bulk senders from major mailbox providers.
Marketer view
Email marketer from Email Geeks states that their understanding has always been that DMARC does not directly improve deliverability, but rather helps with brand trustworthiness and security.
21 Aug 2020 - Email Geeks
Marketer view
An email marketer from Twilio suggests that DMARC records are important and can enhance campaign email delivery by reducing the likelihood of emails being flagged as spam. This can improve overall inbox placement.
22 Jun 2024 - Twilio
What the experts say
Email deliverability experts offer nuanced perspectives on DMARC, emphasizing its primary role in security and governance over direct deliverability improvement. They highlight the complexities of implementation, the potential for unintended negative consequences if not handled carefully, and the importance of focusing on core authentication practices.
Key opinions
Not a direct deliverability tool: Experts widely agree that DMARC itself does not directly improve deliverability, but rather serves as a mechanism for domain authentication and abuse prevention.
Complexity and governance: DMARC deployments are complex and require careful management; they are more of a governance decision than a simple technical switch. Misconfigurations can cause significant harm to legitimate email flows.
Potential for lower deliverability: When enforced, a DMARC policy can lower deliverability by design if emails are modified in transit or forwarding breaks authentication, causing legitimate mail to fail.
Value of DMARC-aligned SPF and DKIM: Achieving SPF and DKIM alignment, even without a DMARC record, can provide significant benefits, as some mailbox providers check for this alignment regardless. This concept is sometimes referred to as 'VirtualDMARC'.
Reporting is key: The reporting feature of DMARC is highly valued by experts for providing visibility into email streams and potential abuse, even if the policy statements are seen as less effective.
Key considerations
Avoiding premature enforcement: ESPs should advise against forcing DMARC with strong policies (p=quarantine or p=reject) until SPF and DKIM are fully aligned and monitored, as this can lead to legitimate emails failing authentication. This is part of the best practices for DMARC implementation.
Role of ESPs: ESPs should primarily focus on supporting and promoting SPF and DKIM alignment for their customers, ensuring their sending infrastructure is correctly configured for DMARC. This is crucial as DMARC is now required for bulk senders.
Understanding email use: Some experts argue that DMARC policy is based on a fundamental misunderstanding of how people actually use email, especially regarding forwarding and modifications in transit.
ARC limitations: While ARC (Authenticated Received Chain) aims to preserve authentication results across forwarding, its limited support and lack of reputational attribution make it less effective in current scenarios.
Expert view
Deliverability expert from Email Geeks states that DMARC does not directly improve deliverability. Its function is primarily in authentication and policy enforcement, not direct inbox placement.
21 Aug 2020 - Email Geeks
Expert view
Deliverability expert from Word to the Wise suggests that DMARC deployments are complex and should not be treated as a simple 'fire and forget' DNS record, especially when considering reporting implications.
15 Apr 2024 - Word to the Wise
What the documentation says
Official documentation and industry guidelines emphasize DMARC's role in email security and anti-spoofing efforts. While not always explicitly stating a direct deliverability boost, they highlight how DMARC contributes to a trustworthy email ecosystem, which implicitly supports inbox placement by reducing the amount of fraudulent mail.
Key findings
Security goal: The primary goal of the DMARC specification is to enhance email security by helping receivers identify legitimate messages from a domain and detect spoofed ones.
Brand protection: DMARC helps protect an organization's brand reputation by allowing domain owners to specify how unauthenticated emails purporting to be from their domain should be handled by receiving servers. For example, by telling receiving servers to reject emails that fail DMARC, a company can ensure that fraudulent emails appearing to be from them never reach customers.
Authentication foundation: DMARC leverages the existing SPF and DKIM authentication mechanisms, requiring at least one of them to align with the From header domain.
Reporting: A key component of DMARC is its reporting capability, which provides valuable feedback to domain owners on authentication results and potential abuse patterns.
Bulk sender requirements: Recent updates from major mailbox providers (e.g., Gmail, Yahoo) now mandate DMARC implementation for bulk senders, making it a de facto requirement for maintaining deliverability. This is outlined by Microsoft's new requirements.
Key considerations
Phased deployment: Documentation recommends a phased approach to DMARC implementation, starting with a p=none policy to gather data before moving to quarantine or reject policies.
Alignment critical: Proper alignment of SPF and DKIM with the organizational domain is crucial for DMARC to pass, even if an explicit DMARC policy is not yet enforced.
Impact on unauthenticated messages: A DMARC policy explicitly instructs receiving servers on how to handle messages that fail authentication, providing a clear directive for unauthenticated email. This is explained by Webex Connect.
Not a standalone solution: DMARC works in conjunction with SPF and DKIM. It's not a standalone solution for deliverability issues, which often stem from content, reputation, or list quality problems. More information on implementing DKIM, SPF, and DMARC can be found here.
Technical article
Documentation from Twilio emphasizes that a DMARC record is important for improving campaign's email delivery and helping avoid spam folders, along with providing a sample configuration.
22 Jun 2024 - Twilio
Technical article
Documentation from Email on Acid states that DMARC assists email senders in protecting their brand reputation while also offering valuable reports on the IP addresses sending mail on their behalf.