Does Google penalize for not using email encryption and how does it affect deliverability?
Michael Ko
Co-founder & CEO, Suped
Published 25 Jun 2025
Updated 19 Aug 2025
7 min read
The question of whether Google penalizes senders for not using email encryption, and how that affects deliverability, is a common one among those of us working in email. It is understandable to be concerned about anything that might impact your ability to reach the inbox, especially with major providers like Gmail introducing stricter sender requirements.
At its core, email encryption, primarily through Transport Layer Security (TLS), is about securing data in transit. It ensures that your email content is scrambled and protected from eavesdropping as it travels across networks. When an email is sent without encryption, it is essentially like sending a postcard, readable by anyone who might intercept it.
While Google's stance on this isn't a straightforward penalty system in the same way they treat spam rates or authentication failures, the absence of encryption does play a role in how your emails are perceived and handled. It’s a factor in the broader landscape of trust and security that modern email providers prioritize for their users.
Understanding email encryption and TLS
Email encryption using TLS is a fundamental security measure in today's digital communication. When you send an email, it often travels through multiple servers before reaching its destination. TLS encrypts this communication, protecting the privacy and integrity of the message as it moves from one server to another. This prevents unauthorized parties from easily reading or tampering with your email while it's in transit.
Google, as a leading email service provider, has been a strong advocate for encryption. They visibly indicate when an email connection is unencrypted by displaying an open lock icon or a red lock icon to users, signifying that the message was not encrypted during its journey. This transparency aims to educate users about the security of their communications and encourages senders to adopt encryption. You can learn more about email encryption in Gmail on their support pages.
While the absence of TLS doesn't automatically trigger a hard block or a direct penalty score from Google, it does affect the overall perception of your email's trustworthiness. A visible warning sign about unencrypted communication can erode recipient trust and may indirectly influence how recipients interact with your emails, potentially leading to lower engagement, increased spam complaints, and a damaged sender reputation. It is always a good practice to ensure your emails are sent with TLS enabled for email deliverability.
Google's indirect impact on deliverability
Google's primary concern is user safety and experience. While they don't explicitly state that lack of TLS will penalize a sender, their systems consider multiple signals to determine inbox placement. A consistently unencrypted mail stream, especially for transactional or marketing emails, could contribute to a lower overall sender reputation. This lower reputation may then lead to your emails being filtered into the spam folder, or even being blocked (blacklisted) by Google's sophisticated spam defenses.
The recent Gmail and Yahoo bulk sender requirements, effective February 2024, emphasize strong email authentication like SPF, DKIM, and DMARC. While these protocols do not directly provide encryption, they establish trust and verify sender identity, which is crucial for preventing phishing and spoofing. An email without TLS, even if authenticated, introduces a security gap that Google's systems are designed to highlight and discourage.
Encrypted email (TLS)
Emails sent with TLS are protected in transit, making it harder for unauthorized parties to intercept their content. This builds a layer of trust.
Perception: Recipients see a secure connection (no red lock), reinforcing brand credibility and safety.
Trust signals: Contributes positively to overall sender reputation, helping with Gmail's spam defenses and deliverability.
Data security: Protects sensitive information exchanged via email.
Unencrypted email (no TLS)
Emails without TLS are sent in plain text, making them vulnerable to interception. This lack of security can trigger warnings.
Perception: Recipients may see an unencrypted warning, which can cause concern and lead to distrust.
Deliverability: Can indirectly harm sender reputation, increasing the likelihood of emails landing in spam folders or being blocklisted.
Privacy risk: Sensitive data (like email addresses in URLs) can be exposed, which might trigger privacy violations.
Even without a direct penalty, the signal of an unencrypted connection to Google and other major mailbox providers (like Yahoo) is considered a negative factor. It suggests a lack of attention to security best practices, which can gradually degrade your domain's reputation. This degradation means your emails are more likely to be subjected to stricter filtering, potentially leading to more messages being marked as spam or even triggering blocklisting (or blacklisting) of your sending IP or domain. The goal is to maximize the positive signals you send to mailbox providers and minimize any negative ones.
Beyond the red lock: Reputation and user perception
Beyond the technical aspects, the absence of email encryption affects user perception and trust. When a recipient sees a warning about an unencrypted email, it can raise concerns about the legitimacy of the message and the sender. This can lead to decreased open rates, lower click-through rates, and a higher likelihood of recipients marking your emails as spam, even if the content is relevant.
Moreover, if personal identifiable information (PII) like email addresses is passed unencrypted in URLs within your emails, this can be a significant issue. Google has strict policies regarding the handling of PII, and while it might not directly affect your email deliverability in the same way a spam complaint does, it signals poor privacy practices. This is a separate but related concern, as it impacts how you handle user data. You can learn more about how including email addresses in URL links affects deliverability.
An overall secure email sending posture contributes to better deliverability. This includes not just encryption, but also robust authentication mechanisms like SPF, DKIM, and DMARC. These protocols work together to verify that your emails are legitimate and that they haven't been tampered with. Mailbox providers like Google use these signals to build a comprehensive picture of your sender reputation.
Best practices for email encryption
Always use TLS: Ensure your email service provider (ESP) supports and enforces TLS 1.2 or higher for all outbound emails. Most reputable ESPs do this by default.
Monitor your send status: Utilize Google Postmaster Tools to check your domain's health, including TLS encryption rates, and identify any issues.
Implement DMARC: Alongside TLS, implement DMARC, SPF, and DKIM to authenticate your emails. This combination significantly boosts your email authentication and sender trust.
Educate your team: Ensure anyone sending emails understands the importance of encryption and secure sending practices.
Implementing email encryption and authentication
Ensuring your emails are encrypted with TLS is typically handled at the server level by your email service provider or mail server administrator. Most reputable ESPs configure TLS automatically. However, it's always good practice to verify that your sending infrastructure supports and actively uses TLS for all outgoing mail. You can often check this through your ESP's documentation or by contacting their support.
While TLS provides encryption in transit, it is just one piece of the email security puzzle. Protocols like SPF (Sender Policy Framework), DKIM (DomainKeys Identified Mail), and DMARC (Domain-based Message Authentication, Reporting, and Conformance) are critical for email authentication. These mechanisms verify that an email truly originates from the claimed sender and has not been altered, thereby preventing spoofing and phishing attacks. Together, encryption and authentication form a robust defense, significantly improving your email deliverability.
Check your DMARC record to see your security configurationbash
dig TXT _dmarc.yourdomain.com
Continuously monitoring your email delivery is essential. Tools that provide insights into your TLS usage rates, DMARC reports, and sender reputation metrics can help you identify and address potential issues proactively. Maintaining a high level of email security and compliance ensures that your messages reach their intended recipients reliably, fostering trust with both mailbox providers and your audience.
Views from the trenches
Best practices
Always prioritize enabling Transport Layer Security (TLS) for all outbound email to ensure data privacy and integrity during transmission.
Regularly monitor your email service provider's TLS connection reports to identify any unencrypted email streams.
Implement robust email authentication protocols like SPF, DKIM, and DMARC, as they complement TLS in building sender trust.
Keep your email infrastructure updated to support the latest TLS versions, typically TLS 1.2 or higher, for optimal security.
Maintain a clean and engaged email list to reduce spam complaints, which can indirectly impact deliverability regardless of encryption status.
Common pitfalls
Assuming your email service provider automatically encrypts all emails without verification, leading to unencrypted transmissions.
Ignoring Google's visible 'red lock' warning, which indicates a lack of encryption and can erode recipient trust.
Confusing TLS email encryption with end-to-end encryption or email authentication protocols like DMARC, SPF, and DKIM.
Passing sensitive personal identifiable information, such as email addresses, unencrypted in URLs within your email campaigns.
Failing to regularly check your domain's reputation with Google Postmaster Tools, missing key signals about deliverability performance.
Expert tips
Encryption (TLS) for email is a fundamental hygiene factor. While Google may not directly penalize it like a spam trigger, it's factored into overall inbox placement because it impacts trust.
When integrating third-party services, confirm their TLS support. Some older systems might default to unencrypted connections, impacting your aggregate reputation.
Think of TLS as foundational. Without it, even perfect authentication (SPF/DKIM/DMARC) has a security gap that modern spam filters account for.
A clear indication of unencrypted email to recipients (the 'red lock' icon) directly impacts user engagement and can lead to increased spam reports, which Google does penalize.
Ensure your DNS settings for MX records and other relevant entries are correctly configured to facilitate TLS negotiations for incoming and outgoing mail.
Marketer view
Marketer from Email Geeks says they expect that a lack of encryption would be factored into inbox placement, as it likely does not make providers happy.
2018-08-10 - Email Geeks
Marketer view
Marketer from Email Geeks says they experienced penalties for not encrypting email addresses passed in URLs, but not for full email encryption yet.
2018-08-10 - Email Geeks
Key takeaways
While Google may not impose a direct, explicit penalty solely for the absence of email encryption, its impact on deliverability is significant yet indirect. The visible warnings to users and the contribution to your overall sender reputation are crucial factors. Prioritizing TLS encryption, alongside robust authentication protocols like SPF, DKIM, and DMARC, is essential for maintaining trust with mailbox providers and ensuring your emails consistently reach the inbox.
