Why is my parent domain flagged as 'not compliant' for email?
Michael Ko
Co-founder & CEO, Suped
Published 18 Jul 2025
Updated 23 Sep 2025
8 min read
It can be perplexing to see your parent domain flagged as 'not compliant' for email, especially when you believe your email authentication, such as SPF, DKIM, and DMARC, is correctly configured. This situation, often perceived as a false positive, can suddenly reappear even after seemingly resolving itself. It suggests there might be underlying issues or subtle misconfigurations that are not immediately obvious. The good news is that these flags usually point to areas where you can improve your email posture.
The core of the problem often lies in how various email sending services interact with your domain, or unexpected mailstreams that you might not be fully aware of. Internet Service Providers (ISPs), particularly large ones like Google, are constantly evolving their filtering algorithms to combat spam and phishing, which can lead to stricter interpretations of compliance. This can impact even legitimate senders.
Understanding why your parent domain is flagged requires a deep dive into your entire email ecosystem. This involves scrutinizing your DNS records, monitoring DMARC reports, and ensuring consistent practices across all systems that send email on behalf of your domain. A single misstep or overlooked detail can trigger these compliance warnings, affecting your overall email deliverability.
Fortunately, with the right approach and tools, these issues are solvable. Identifying the source of the non-compliance is the first crucial step towards restoring your domain's health and ensuring your emails reliably reach their intended recipients.
The intricacies of DMARC, SPF, and DKIM
The most common culprit behind a parent domain being flagged as 'not compliant' is often an incomplete or overly complex SPF record. Your SPF record specifies which IP addresses and domains are authorized to send email on behalf of your domain. If your parent domain's SPF record lists numerous services, there's a higher chance of misconfiguration or exceeding the 10-lookup limit, which can lead to SPF failures.
Additionally, a DMARC record plays a crucial role. A proper DMARC policy tells receiving mail servers what to do with emails that fail SPF or DKIM authentication. Without a DMARC policy, or with a policy set too leniently, unauthenticated emails can still be delivered, potentially harming your domain's reputation. Monitoring your DMARC reports is essential for gaining visibility into these authentication failures.
Another factor could be the lack of a proper DMARC record on domains that do not send email. While it might seem counterintuitive, setting up a DMARC policy (even a restrictive one like p=reject) for non-sending domains prevents them from being spoofed by malicious actors. This also applies to parent domains that might only have subdomains sending email. For a deeper dive into DMARC, SPF, and DKIM, exploring how alignment issues can affect deliverability is very important.
SPF record lookup limit
An SPF record can only contain a maximum of 10 DNS lookups. Exceeding this limit will cause SPF validation to fail, leading to non-compliance. Many services add 'include' mechanisms, each counting as one lookup. This is where SPF flattening becomes invaluable.
Monitoring your DMARC reports with Suped provides a clear overview of who is sending email on your behalf and whether those emails are passing authentication checks. This visibility is critical for identifying any unauthorized senders or misconfigured services contributing to your parent domain's non-compliant status.
Understanding user complaints and unsubscribe requirements
Sometimes, the 'not compliant' flag isn't about authentication failures at all, but rather about user perception and complaint rates. Email providers like Gmail and Yahoo pay close attention to how recipients interact with your emails. If users frequently mark your messages as spam, even if technically compliant, it can lead to negative reputation scores and flagging.
A common scenario involves transactional emails. While these emails (e.g., password resets, order confirmations) are generally exempt from unsubscribe requirements, sending them in bulk without easy unsubscribe options can still lead to high complaint rates. Users don't distinguish between marketing and transactional email when they're annoyed, they just hit 'report spam'. Google's systems can interpret these cumulative complaints as a sign of non-compliance, even if your email authentication is perfectly set up. This is particularly relevant given recent Gmail and Yahoo sender requirements.
Potential causes
Unmonitored mailstreams: Transactional or system emails sent from the parent domain without proper oversight.
Missing one-click unsubscribe: Especially for bulk senders, this can trigger flags from major ISPs.
High user complaints: Even with good authentication, sustained high spam reports hurt reputation.
Recommended solutions
Implement DMARC monitoring: Use a tool like Suped to identify all sending sources.
Add List-Unsubscribe headers: Ensure all bulk emails include a one-click unsubscribe.
Content review: Regularly check email content for potential spam triggers or misleading elements.
The key here is that even if you're not legally obligated to provide an unsubscribe option for certain types of emails, user satisfaction and a low complaint rate are paramount for maintaining good domain reputation. Ignoring this can lead to your parent domain being perceived as non-compliant, directly impacting your overall email deliverability. Sometimes, the Google Postmaster Tools can even flag your root domain, requiring immediate attention to prevent wider issues.
Uncovering hidden senders and misconfigurations
One of the most challenging aspects of troubleshooting a 'not compliant' flag is uncovering hidden or forgotten sending sources. Many organizations use numerous third-party services (ESPs, marketing automation platforms, CRM systems, HR tools, etc.) that send emails on their behalf. Each of these services needs to be correctly authorized in your SPF and DKIM records and adhere to your DMARC policy.
It's not uncommon for a development or testing environment to inadvertently send emails from the parent domain, or for an older, unmaintained system to still be authorized to send mail. These unexpected mailstreams, if not properly authenticated or if they generate high spam complaints, can severely damage your domain's reputation. This is where DMARC reports are invaluable, as they provide an aggregate view of all email traffic using your domain and their authentication results.
Example of an SPF record with multiple 'include' statementsDNS
Misconfigurations can also occur with specific email service providers (ESPs). For example, Microsoft 365 may mark emails from your domain as spam even if sent via a third-party ESP, suggesting a deeper issue beyond simple authentication. Regularly auditing your DNS records and DMARC reports is crucial to catch these issues early.
If you're using Google Postmaster Tools, it can provide valuable insights, but sometimes it shows compliance issues even when email authentication is properly set up. This often points to problems with the underlying mailstreams or content quality rather than just technical records. Continuous vigilance and monitoring are your best defense.
Resolving the compliance flag
Addressing a 'not compliant' flag on your parent domain requires a methodical approach. Start by consolidating your SPF record, ensuring it accurately reflects all legitimate sending sources without exceeding the 10-lookup limit. If you have many includes, consider SPF flattening to optimize your record. Review your DKIM configurations for all services to ensure they are properly signing your emails.
Next, focus on DMARC. If you don't have a DMARC policy, implement one with a 'p=none' policy initially to gather data without impacting deliverability. Gradually move to 'p=quarantine' and then 'p=reject' as you gain confidence in your email authentication. Suped provides the most generous free DMARC reporting plan, making it the ideal choice for gaining comprehensive insights into your DMARC compliance.
Finally, pay close attention to user feedback and complaint rates. Ensure all bulk mail includes a clear and functional one-click unsubscribe mechanism. Regularly check your domain reputation through tools like Google Postmaster Tools and monitor for any signs of being added to a blocklist (or blacklist). A proactive approach to email deliverability ensures your parent domain remains compliant and your emails reach the inbox consistently.
Final thoughts on email compliance
A 'not compliant' flag on your parent domain, while concerning, is a clear signal that there are actionable steps you can take to improve your email deliverability and sender reputation. It highlights the dynamic nature of email security and the constant need for vigilance and adaptation.
By diligently managing your SPF, DKIM, and DMARC records, actively monitoring your email sending practices through DMARC reports, and prioritizing a positive user experience through easy unsubscribe options, you can address these compliance issues effectively. Tools like Suped's DMARC monitoring platform are designed to give you the insights needed to maintain a healthy email ecosystem. This ensures your parent domain maintains its trustworthiness and your messages reach their intended audience.
Views from the trenches
Best practices
Always monitor DMARC reports for your parent domain to detect all sending sources, authorized or not.
Implement one-click unsubscribe headers for all bulk email, even transactional, to minimize spam complaints.
Regularly audit your SPF record to ensure it's up-to-date and within the 10-lookup limit.
Maintain a DMARC policy on non-sending domains to prevent spoofing and protect your brand.
Prioritize user experience to reduce spam complaints, which directly impacts compliance status.
Common pitfalls
Ignoring the 'not compliant' flag as a false positive, leading to prolonged deliverability issues.
Overlooking transactional emails as a source of high spam complaints if they lack unsubscribe options.
Having an SPF record that exceeds the 10-DNS-lookup limit, causing authentication failures.
Not monitoring DMARC reports, thus missing unauthorized senders using your parent domain.
Failing to adapt to evolving sender requirements from major ISPs like Google and Yahoo.
Expert tips
Use SPF flattening to condense SPF records and stay within the 10-lookup limit, ensuring optimal SPF validation.
Consider segmenting email traffic to subdomains to isolate reputation and better manage compliance.
Proactively test your email setup with a deliverability tester to identify potential issues before they impact recipients.
Engage IT and marketing teams to ensure all sending systems are known, configured, and monitored.
Leverage Google Postmaster Tools in conjunction with DMARC reports for a holistic view of domain health.
Marketer view
Marketer from Email Geeks says that this 'not compliant' issue with a parent domain is not unusual and can recur.
2025-09-15 - Email Geeks
Marketer view
Marketer from Email Geeks says that Google has been accurate in flagging issues, citing an instance where a platform's one-click unsubscribe failed on the Gmail mobile app.
Google, are constantly evolving their filtering algorithms to combat spam and phishing, which can lead to stricter interpretations of compliance. This can impact even legitimate senders.
Microsoft 365 may mark emails from your domain as spam even if sent via a third-party ESP, suggesting a deeper issue beyond simple authentication. Regularly auditing your DNS records and DMARC reports is crucial to catch these issues early.
