Summary
When enforcing DMARC policies for bulk senders currently at p=none, the primary objective is to transition to a stronger policy (like p=quarantine or p=reject) without negatively impacting legitimate email deliverability. This process is often complicated by unidentified legitimate sending sources (sometimes called 'shadow IT') and the potential for spoofing. The consensus among deliverability experts and marketers is to use the p=none period to meticulously identify and authenticate all legitimate email streams, leveraging DMARC reports for comprehensive visibility. Once all authorized sending sources are correctly configured with SPF and DKIM and pass DMARC alignment, then a phased approach to enforcement, moving from p=none to p=quarantine and eventually to p=reject, is recommended. Careful monitoring remains crucial throughout this transition.
Key findings
- Initial stage: The p=none policy is solely for monitoring and collecting DMARC reports, not for enforcement. It provides visibility into who is sending email purporting to be from your domain, whether authorized or unauthorized.
- Prioritize authentication: Before moving to an enforcement policy, it is critical to ensure all legitimate email sending sources are properly authenticated with SPF and DKIM and achieve DMARC alignment.
- Spoofing vs. legitimate traffic: Many flagged emails under p=none might be legitimate but unauthenticated sending services (e.g., 'shadow IT'), not necessarily malicious spoofing. These must be identified and configured correctly.
- Bulk sender requirements: New requirements from major mailbox providers like Gmail and Microsoft mandate that bulk senders publish a DMARC record with at least p=none.
- Phased rollout: A gradual transition from p=none to p=quarantine and then to p=reject is widely recommended to mitigate risks to deliverability.
Key considerations
- DMARC reporting service: Utilizing a DMARC reporting service is essential for interpreting the complex XML reports generated by mailbox providers, making it easier to identify and address authentication issues.
- Apex domain vs. subdomains: If a domain is used for multiple purposes (e.g., business communications, marketing, transactional), consider using subdomains for different email streams. This allows for more granular DMARC policies, reducing the risk of disrupting critical business email. Implementing p=reject at the apex domain can break common business use of email.
- Monitoring duration: Monitor with p=none for at least a month, or until you are confident that all legitimate sending sources are authenticated and aligned, and no unexpected legitimate traffic is failing DMARC.
- Risk assessment: The decision to move to enforcement and the speed of transition depend on the client's risk tolerance for potential non-delivery of a small subset of legitimate emails.
- Quarantine vs. reject: While p=quarantine and p=reject have different instructions for receiving servers (send to spam vs. reject entirely), for most practical purposes, mail failing authentication with either policy will not reach the inbox.
What email marketers say
Email marketers often approach DMARC enforcement with a focus on practical impact, particularly on open rates and campaign performance. Their discussions revolve around the immediate challenges of identifying and authenticating all email streams, especially when dealing with a domain that serves multiple purposes. The key concern is how to transition to a stronger DMARC policy without inadvertently blocking legitimate marketing or transactional emails, underscoring the importance of thorough preparation and monitoring. They emphasize the need for clear understanding of DMARC reports and the potential for 'shadow IT' to cause unexpected authentication failures.
Key opinions
- Address issues proactively: It is better to identify and resolve issues with probable spoofers or unauthenticated legitimate sources while the DMARC policy is still set to p=none. This allows for necessary adjustments without immediate negative impacts on deliverability.
- Complex domain usage: When a domain is used for a variety of email types, such as general business communications, marketing, and transactional emails, the DMARC implementation becomes more complex. Each type of traffic needs careful consideration regarding its authentication.
- Impact on open rates: Maintaining good open rates is a primary concern. Marketers aim to prevent legitimate emails from being sent to spam or rejected due to DMARC enforcement.
- DMARC report interpretation: Understanding and interpreting DMARC reports can be challenging, especially for those new to deliverability. A dedicated DMARC reporting service is highly beneficial.
Key considerations
- Authentication first: The fundamental advice is to authenticate all legitimate sending sources before contemplating a move to a stronger policy like p=quarantine or p=reject. This ensures known good mail flows correctly.
- Subdomain strategy: For domains with multiple email uses, particularly for marketing and transactional emails, consider sending from subdomains. This allows for more granular and safer DMARC enforcement.
- Using an external service: If unfamiliar with reading DMARC reports, sign up for a service that simplifies interpretation and assists in the journey towards enforcement. For bulk senders, compliance with requirements from providers like Microsoft is key; they require at least a p=none DMARC policy.
- Continuous monitoring: Even after moving to enforcement, continuous monitoring of DMARC reports is essential to catch any new legitimate sources or configuration issues. You can learn more about how DMARC improves email deliverability on our site.
Marketer view
Marketer from Email Geeks explains. The client I'm working with is a bulk sender, and we've already set up DMARC with a p=none policy. My concern is that more than 600 emails were flagged, and I'm unsure whether to address these probable spoofers while keeping DMARC at p=none, or if it's better to move directly to p=quarantine. The goal is to maintain good open rates.
Marketer view
Marketer from Iterable's blog post suggests. It's crucial to begin with a 'none' policy to effectively monitor all your email sources. This initial phase helps identify legitimate mail streams and ensures they all pass DMARC authentication before moving to stricter policies. This step is foundational for a smooth transition and ensures ongoing deliverability.
What the experts say
Email deliverability experts consistently advocate for a structured, data-driven approach to DMARC enforcement. They emphasize that while p=none is a crucial monitoring phase, the ultimate goal is to move to a policy that offers true protection against spoofing and phishing. A significant challenge they highlight is the discovery of 'shadow IT,' where legitimate email streams are found to be unauthenticated due to internal oversight. Experts stress the importance of robust DMARC reporting services and a thorough understanding of how DMARC policies interact with different types of email traffic, especially when a single domain handles multiple functions.
Key opinions
- Authenticate first, then enforce: The primary step is to authenticate all legitimate sources sending mail from your domain. Only after this is complete and verified can enforcement policies be safely applied.
- Identify 'shadow IT': A crucial part of the p=none monitoring phase is identifying any legitimate email sources that are not yet authenticated (often referred to as 'shadow IT'). These unauthenticated legitimate sources will show up as failures in DMARC reports.
- Apex domain risks: Applying a DMARC p=reject policy to an apex domain that handles diverse email types (e.g., business communications, marketing, transactional) carries a significant risk of breaking legitimate email flows.
- Policy similarity: In practice, DMARC's p=quarantine and p=reject policies often behave similarly regarding non-delivery of unauthenticated mail. While one directs to spam and the other rejects, both prevent the message from reaching the primary inbox.
Key considerations
- Use a DMARC reporting service: Given the complexity of DMARC aggregate reports, using a specialized DMARC reporting service is highly recommended for accurate interpretation and to guide the path to enforcement. You can also monitor your DMARC reports from Google and Yahoo.
- Monitor for sufficient duration: Experts suggest monitoring at p=none for at least one month, or longer if significant unauthenticated legitimate traffic is still being discovered. The duration should be based on confidence that all sources are identified.
- Subdomain implementation: If marketing and transactional emails are sent from subdomains, it is strongly recommended to treat these subdomains separately from the apex domain in terms of DMARC policy. This offers greater control and minimizes risk.
- Phased enforcement: Once satisfied with the p=none data, the next step is to 'pull the trigger' and move to a stronger policy. This transition should be managed carefully, continuously reading reports to catch any unforeseen issues. Mailgun provides a guide on how to implement DMARC policies.
Expert view
Expert from Email Geeks advises. The fundamental step in DMARC implementation is to authenticate all legitimate email sources for your domain. Once these sources are properly authenticated and aligned with your DMARC record, you can then proceed to enforce stronger DMARC policies like quarantine or reject. Ignoring this crucial initial step can lead to legitimate emails being inadvertently impacted or blocked, causing deliverability issues.
Expert view
Expert from Wordtothewise.com advises. When a domain is used for diverse email purposes, such as marketing, transactional, and general business communications, it's often beneficial to use subdomains. This strategy allows for more granular DMARC policies, where different policies can be applied to different traffic types, significantly reducing the risk of accidental blocking for critical emails and enhancing overall deliverability management.
What the documentation says
Official documentation and industry standards consistently emphasize the monitoring role of DMARC's p=none policy, particularly for bulk senders. They highlight its importance in gathering data on email authentication without imposing immediate actions. The documentation strongly advises a gradual, phased approach to DMARC enforcement, moving from none to quarantine and then to reject, ensuring that all legitimate email streams are authenticated and aligned. Compliance with these authentication protocols, including DMARC with at least p=none, is increasingly becoming a prerequisite for good deliverability from major mailbox providers.
Key findings
- Monitoring policy: The p=none policy is specifically designated for monitoring purposes. It allows domain owners to observe unauthenticated email traffic without taking any enforcement actions like quarantining or rejecting messages.
- Bulk sender requirements: Leading mailbox providers such as Google and Microsoft now require bulk email senders to publish a DMARC record with at least a p=none policy, alongside proper SPF and DKIM authentication.
- Phased enforcement encouraged: Official guidelines recommend a gradual progression of DMARC policies: starting with p=none, moving to p=quarantine, and finally to p=reject. This measured approach helps prevent disruption to legitimate email.
- Alignment is key: Successful DMARC implementation hinges on ensuring that emails pass either SPF or DKIM authentication and that these authenticators are properly aligned with the domain in the 'From' header.
Key considerations
- Data collection: The p=none policy allows for critical data collection on email sending practices without any impact on email delivery. This data is vital for identifying all legitimate sources.
- DMARC record publication: The initial step is always to publish a DMARC record, even if it is just at p=none. This signifies the domain's intent to implement DMARC and begin receiving reports.
- Ensuring SPF and DKIM: Before strengthening the DMARC policy, it is imperative to ensure that all legitimate email is properly authenticated with SPF and DKIM, and that these records are correctly configured and aligned.
- Long-term goal: While p=none is a starting point, the ultimate goal for strong brand protection is to move towards p=quarantine or p=reject to mitigate spoofing and phishing risks. This transition should be undertaken carefully, as outlined in guides such as DuoCircle's use cases for DMARC policies.
Technical article
Documentation from Email on Acid outlines. Every sender now needs to employ SPF and DKIM for email authentication, as these are foundational security protocols. For bulk senders specifically, implementing DMARC with a minimum policy of p=none is a current requirement to comply with evolving industry standards. This foundational step ensures basic compliance and provides crucial reporting data to monitor email activity.
Technical article
Documentation from Mailgun recommends. The DMARC policy (represented by the 'p=' tag) should be progressively evolved over time, similar to a traffic light system moving from green to red. It is advised to gradually transition from an initial p=none policy, which is for monitoring, to p=quarantine, and finally, to the most stringent policy, p=reject. This phased approach minimizes disruptions to legitimate email flows during implementation.
Related resources
13 resources
Related pages
When should you use DMARC p=none, p=quarantine, or p=reject policies?
How to implement DMARC p=reject policy safely to avoid email deliverability issues?
How to safely transition your DMARC policy to quarantine or reject
What are the best practices for setting DMARC policy, particularly p=reject?
Simple DMARC examples: how to start with a p=none policy
When switching DMARC configuration from none to quarantine, is it best to do so in increments, or all at once?
Does implementing DMARC improve email deliverability and is DMARC p=none policy useful?
Understanding and troubleshooting DMARC reports from Google and Yahoo
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Why Your Emails Fail: Expert Guide to Improve Email Deliverability [2025]
