Best practices for email deliverability to government and .mil accounts.
Matthew Whittaker
Co-founder & CTO, Suped
Published 27 Jun 2025
Updated 19 Aug 2025
5 min read
Email deliverability is a complex challenge, but sending messages to government and .mil accounts presents a unique set of hurdles. These domains operate under stringent security protocols designed to protect sensitive information, often leading to aggressive spam filtering and unusual email rendering behaviors. My experience has shown that what works for commercial inboxes may not apply here.
The strictness is understandable, given the nature of the communications. For anyone trying to reach these critical contacts, navigating these policies is essential for ensuring your legitimate emails actually land in the inbox. It's not just about avoiding the spam folder, it's about understanding an entirely different digital ecosystem.
Understanding the .gov and .mil landscape
Sending emails to .gov and .mil domains is fundamentally different from sending to commercial or B2B addresses. These domains are controlled by federal and military entities that prioritize security above almost everything else. This means their email systems often employ advanced threat protection, content filtering, and strict authentication checks.
One significant policy I've encountered is the Department of Defense (DoD)'s stance on external communication. They often have internal policies that restrict or break links from non-.mil domains to prevent malware and phishing attacks. This makes traditional marketing emails, which rely heavily on clickable links and rich media, largely ineffective.
Bulk marketing messages are almost guaranteed not to reach .mil inboxes. In some cases, email service providers have even historically suppressed all .mil accounts due to the intense scrutiny and potential legal ramifications, such as those related to CAN-SPAM Act compliance. Understanding these foundational differences is your first step toward improved deliverability.
Authentication is non-negotiable
Proper email authentication is paramount for any sender, but it becomes an absolute necessity when targeting government and military accounts. SPF, DKIM, and DMARC are not just suggestions, they are critical gatekeepers. Without robust authentication, your emails are unlikely to even reach the spam folder, let alone the inbox.
I always recommend aiming for the highest level of DMARC enforcement (p=reject) for your sending domains. This tells receiving servers, including those at .gov and .mil, that you are serious about preventing spoofing and unauthorized use of your domain. This commitment to security can significantly enhance your sender reputation.
Beyond the basic setup, regularly monitor your DMARC reports to identify any authentication failures or unauthorized sending. This proactive approach helps maintain a clean sending record. For more information on setting up these records, check out a simple guide to DMARC, SPF, and DKIM. To safely transition your policy, learn how to safely transition your DMARC policy.
Content and formatting considerations
The content and formatting of your emails are critical, especially when dealing with the high security of .gov and .mil domains. Many of these agencies will not render HTML or images due to security risks. This means fancy templates, embedded videos, or even tracking pixels are often stripped out or blocklisted (blacklisted).
My recommendation is to prioritize plain text emails whenever possible. If you must use HTML, ensure it's extremely lightweight, clean, and accessibility-friendly. Assume images won't render and links won't be clickable. Convey your message clearly in the body text.
Subject lines should be direct, informative, and devoid of any spammy triggers. Avoid excessive capitalization, exclamation points, or vague language. Clarity and conciseness are key to getting your email opened and understood within these environments. You also need to ensure your email 'From' addresses are professional.
Content for .gov and .mil
Plain text: Design emails with minimal HTML. Assume images will not load and links will be broken or disabled.
Directness: Get straight to the point. Government officials prefer clear, concise communication without extraneous marketing fluff.
Subject lines: Keep them professional, accurate, and descriptive to avoid spam filters.
Reputation and monitoring
Sender reputation is always vital, but government and military domains often use specific, very strict criteria for evaluating it. They commonly rely on reputation services that assign a numerical score to IP addresses and domains. For instance, many .gov domains reportedly require a very high sender score, often above 80 out of 100, for emails to be delivered.
This means even if your overall reputation is considered 'good' by general standards, it might not be sufficient for these highly protected environments. Consistent positive sending behavior and avoiding any activities that could land you on a blocklist (or blacklist) are crucial. Review our comprehensive guide to email blocklists.
Monitoring your sender reputation proactively and performing regular email deliverability tests is a practice I cannot emphasize enough. Staying off blocklists (blacklists) and maintaining high engagement with your valid subscribers will directly influence your ability to reach these unique inboxes. For additional tips, consider emailing military and overseas voters documentation.
General email deliverability
Broad audience: Focus on engagement across various ISPs (Gmail, Outlook, Yahoo).
Content flexibility: HTML, images, and links are commonly used and expected.
Reputation scores: Good/neutral status is often sufficient for inbox placement.
Government and .mil deliverability
Highly targeted: Extreme focus on specific security protocols of .gov and .mil domains.
Plain text preference: HTML and interactive elements are often stripped or blocked.
Strict reputation: Often requires very high numerical sender scores (e.g., 80+/100).
Views from the trenches
Best practices
Always prioritize strong email authentication: SPF, DKIM, and DMARC with a 'reject' policy.
Send emails in plain text format as much as possible, avoiding complex HTML or images.
Ensure subject lines are clear, concise, and professional, free of marketing jargon.
Understand and comply with specific security policies of government domains.
Maintain a high sender reputation through consistent positive sending behaviors.
Common pitfalls
Sending bulk marketing emails with rich HTML and embedded links to .mil accounts.
Assuming standard commercial email deliverability practices apply to government domains.
Neglecting to monitor DMARC reports for authentication failures and unauthorized sending.
Not understanding the high reputation score thresholds required by some .gov domains.
Using deceptive subject lines or 'From' addresses, which can lead to immediate blocking.
Expert tips
If interactive content is necessary, consider alternative communication channels or follow-up methods.
Regularly review governmental email guidelines and updates, as policies can evolve.
For specific .mil interactions, confirm if direct, one-to-one communication is permissible, even then, expect high filtering.
Focus on building relationships and trust, as whitelisting may be the only way for consistent delivery.
Segment your lists to separate government contacts, allowing for tailored sending strategies.
Expert view
Expert from Email Geeks says that some deliverability issues are unavoidable, especially with DoD policies that break links to prevent malware. Senders must be aware of and make allowances for these policies.
2019-08-16 - Email Geeks
Marketer view
Marketer from Email Geeks says that bulk marketing messages will almost never get to the inbox for military accounts because of a DoD policy against communicating with non-.mil domains.
2019-08-16 - Email Geeks
Key takeaways for successful deliverability
Email deliverability to government and .mil accounts is not a one-size-fits-all problem. It requires a nuanced approach that accounts for their unique security posture and communication policies. Success hinges on a combination of strong technical foundations, careful content construction, and an understanding of their specific filtering mechanisms.
By prioritizing robust authentication, opting for simpler email formats, diligently managing your sender reputation, and acknowledging the inherent restrictions of these domains, you significantly increase your chances of reaching these sensitive inboxes. This focused strategy will help you navigate the complexities and achieve better deliverability to this critical audience.
