Why does Gmail block emails with unicode characters or emojis in the from address?

Summary

Gmail blocks emails with Unicode characters or emojis in the 'From' address due to a combination of technical, policy, and security concerns. Issues arise from encoding variations leading to display errors, the triggering of spam filters due to unconventional characters, and the potential for malicious actors to exploit these characters for phishing or spoofing attempts. Furthermore, Google reserves the right to disallow specific images or characters in the 'From' field. Guidelines set forth by RFC standards, Unicode Consortium, DKIM, and Google itself dictate that certain characters are restricted to maintain compatibility and prevent misinterpretation.

Key findings

  • Encoding Issues: Different email clients interpret character encoding differently, causing potential display issues and triggering spam filters.
  • Spam Filter Triggers: Unconventional characters and emojis increase spam scores, leading to emails being blocked or sent to the spam folder.
  • Phishing/Spoofing Risk: Unicode characters and emojis can be used in phishing attempts to mimic legitimate senders.
  • Policy Restrictions: Google has specific policies disallowing certain characters and images in the 'From' field.
  • Compatibility Issues: Some mail systems do not support or display emojis correctly, leading to message rejection.
  • Deliverability Impact: The use of non-standard characters in the sender's information negatively impacts sender reputation and email deliverability.

Key considerations

  • Avoid Unconventional Characters: Refrain from using unicode characters or emojis in the 'From' address to ensure deliverability.
  • Test Character Display: If considering using unicode characters or emojis in other parts of the email, test how they render across different email clients.
  • Monitor Sender Reputation: Consistently monitor your sender reputation to ensure that deliverability issues are not arising from character usage.
  • Follow Header Guidelines: Adhere to the email header specifications detailed in RFC 5322 and other relevant standards.
  • Stay Updated on Policies: Keep up-to-date with the latest email policies and guidelines from providers like Google.

What email marketers say
10Marketer opinions

Gmail blocks emails with unicode characters or emojis in the 'From' address due to several factors related to deliverability and security. These include potential rendering issues across different email clients, increased spam scores leading to filtering, and the risk of phishing or spoofing attempts. The use of these characters can negatively impact sender reputation and may be perceived as unprofessional or untrustworthy.

Key opinions

  • Deliverability Impact: Unicode characters and emojis in the 'From' address can negatively impact email deliverability, causing emails to be blocked or sent to spam.
  • Spam Filtering: Unconventional characters increase spam scores, triggering spam filters in Gmail and other email providers.
  • Phishing/Spoofing Risk: Gmail might block these characters to prevent phishing and spoofing attempts, where bad actors mimic legitimate senders.
  • Encoding Issues: Different email systems interpret encoding differently, leading to display errors or triggering spam filters.
  • Reputation Damage: Using non-standard characters can negatively affect sender reputation and credibility.

Key considerations

  • Encoding Compatibility: Ensure proper encoding of characters to avoid display issues across different email clients.
  • Professionalism: Consider the professional image and credibility of the sender when using special characters or symbols.
  • Deliverability Testing: Test email deliverability across different email providers to identify potential issues with character usage.
  • Sender Reputation: Monitor sender reputation and adjust email practices to maintain a positive standing with email providers.
  • Alternative Characters: Consider using alternative, widely supported characters that convey the intended message without triggering spam filters.
Marketer view

Email marketer from Mailjet warns that while emojis can be effective in subject lines and email body, using them in the 'From' address can negatively impact deliverability and trigger spam filters.

June 2022 - Mailjet
Marketer view

Email marketer from Litmus explains that unconventional characters, including certain unicode characters and emojis, can trigger spam filters and negatively impact email deliverability, particularly if they are not properly encoded or supported by receiving email clients.

June 2023 - Litmus

What the experts say
6Expert opinions

Gmail blocks emails with unicode characters or emojis in the 'From' address due to a combination of technical and policy reasons. These include potential bad encoding, usage of restricted emojis (particularly those resembling verification marks), Google reserving certain images for its own use, display issues in various mail systems, potential triggering of spam filters, and impact on overall deliverability.

Key opinions

  • Encoding Problems: Bad encoding can lead to errors when Gmail processes the email.
  • Restricted Emojis: Gmail disallows specific emojis, especially those that could mislead users (e.g., verification marks).
  • Reserved Images: Google reserves the right to disallow images that it might use itself.
  • Display Issues: Some mail systems might not display emojis correctly, leading to a poor user experience or message rejection.
  • Spam Filter Triggers: Emojis in the 'From' address can trigger spam filters due to encoding variations and potential for abuse.
  • Deliverability Impact: Use of unicode characters and emojis in the 'From' address can negatively affect email deliverability.

Key considerations

  • Avoid Restricted Characters: Refrain from using unicode characters or emojis in the 'From' address that are known to be problematic or could be interpreted as misleading.
  • Test Display Across Clients: If considering using unicode characters or emojis in other parts of the email, test how they render across different email clients to ensure a consistent user experience.
  • Monitor Deliverability: Regularly monitor email deliverability metrics to identify and address any negative impacts resulting from character usage.
  • Consider Alternatives: Explore alternative ways to convey the intended message or branding without relying on potentially problematic characters.
  • Stay Updated on Policies: Stay informed about the latest email policies and guidelines from providers like Google to avoid deliverability issues.
Expert view

Expert from Word to the Wise explains that while emojis can increase engagement in subject lines and body copy, including them in the From: field can create display issues across different email clients and may trigger spam filters due to encoding variations, ultimately impacting deliverability.

August 2022 - Word to the Wise
Expert view

Expert from Email Geeks points to a resource ([https://www.spamresource.com/2023/01/pro-tip-no-emojis-in-friendly-from.html](https://www.spamresource.com/2023/01/pro-tip-no-emojis-in-friendly-from.html)) advising against using emojis in the friendly from address and notes that Google updated the error message for this issue.

November 2024 - Email Geeks

What the documentation says
4Technical articles

Gmail blocks emails with unicode characters or emojis in the 'From' address due to policy restrictions on header content and technical issues related to character encoding and interpretation. These restrictions are detailed in guidelines from Google Support, RFC 5322, and the Unicode Consortium. Using unconventional characters can interfere with email authentication processes like DKIM and cause compatibility problems across different systems.

Key findings

  • Disallowed Header Content: Google Support indicates that messages may be blocked if they contain disallowed header content, which can include unicode characters.
  • Encoding Restrictions: RFC 5322 highlights character encoding restrictions in email headers to ensure compatibility and prevent misinterpretation.
  • Display Variations: The Unicode Consortium notes that the display and interpretation of Unicode characters can vary across systems, causing potential compatibility issues.
  • Authentication Interference: The DKIM standard suggests that unconventional characters in the 'From' address may interfere with authentication processes.

Key considerations

  • Review Guidelines: Consult Google Support's message and header content guidelines to understand specific restrictions.
  • Adhere to Standards: Adhere to the specifications detailed in RFC 5322 regarding character encoding and header formatting.
  • Ensure Compatibility: Be aware of potential compatibility issues when using Unicode characters, and test across different systems.
  • Maintain Authentication: Avoid using characters that may interfere with email authentication mechanisms like DKIM.
Technical article

Documentation from Unicode Consortium explains that while Unicode supports a vast range of characters, the display and interpretation of these characters can vary across different systems and applications, leading to potential compatibility issues in email headers.

August 2021 - Unicode Consortium
Technical article

Documentation from RFC 5322 (Internet Message Format) details the specifications for email headers and character encoding, highlighting restrictions on certain characters to ensure compatibility and prevent misinterpretation by email systems.

December 2023 - RFC Editor