Do all-emoji subject lines hurt email deliverability?

Summary

The impact of all-emoji subject lines on email deliverability is complex and multi-faceted. While emojis can increase open rates and engagement by making emails stand out, there's a significant risk of being flagged as spam, especially with excessive or irrelevant use. Sender reputation, audience demographics, cultural context, and email content all play crucial roles. Experts and documentation consistently recommend strategic and moderate use, A/B testing, and monitoring deliverability metrics to optimize emoji implementation and avoid negatively impacting email deliverability.

Key findings

  • Increased Open Rates: Emojis can catch the reader's eye and increase email open rates.
  • Spam Risk: Excessive or irrelevant emoji use can trigger spam filters, harming deliverability.
  • Audience Matters: The effectiveness of emojis depends on the target audience, brand, and industry.
  • Cultural Context: Emoji meanings and perceptions vary across cultures and age groups.
  • Platform Variation: Emojis may display differently across various email clients and operating systems.

Key considerations

  • Strategic Use: Use emojis strategically, ensuring they are relevant and enhance the message.
  • Moderation: Avoid overusing emojis; a subtle and balanced approach is generally more effective.
  • A/B Testing: A/B test emoji use to determine the impact on open rates, engagement, and deliverability for your specific audience.
  • Sender Reputation: Maintain a good sender reputation, as it influences how spam filters perceive your emails.
  • Relevance: Ensure emojis are relevant to the email's content and avoid using them as mere decoration.

What email marketers say
11Marketer opinions

Using emojis in email subject lines presents a mixed bag of potential benefits and risks. While emojis can increase open rates by making emails stand out, overuse can lead to deliverability issues by triggering spam filters. The impact largely depends on audience, brand, relevance, and strategic use. A/B testing is consistently recommended to determine the optimal approach.

Key opinions

  • Increased Open Rates: Emojis can catch the reader's eye and increase open rates.
  • Spam Trigger: Excessive or irrelevant use of emojis can make emails appear spammy, negatively affecting deliverability.
  • Audience Dependent: The effectiveness of emojis varies based on the target audience and brand personality.
  • Visual Cue: Emojis can serve as a quick visual cue for recipients, potentially leading to immediate deletion if not relevant.
  • Platform Variation: Emojis display differently across apps and operating systems, impacting how they are perceived.

Key considerations

  • Strategic Use: Use emojis strategically and ensure they are relevant to the email content.
  • A/B Testing: Conduct A/B testing to determine the impact of emojis on your specific audience and campaign goals.
  • Audience Appropriateness: Consider whether emojis are appropriate for your target audience, particularly in B2B communications.
  • Frequency: Avoid overusing emojis; a moderate approach is generally more effective.
  • Relevance: Ensure emojis enhance the message and are not simply decorative.
Marketer view

Email marketer from Email Geeks shares that they use emojis in subject lines as a quick visual cue to identify emails they can delete without opening.

November 2022 - Email Geeks
Marketer view

Email marketer from Mailchimp answers that the use of emojis in email subject lines can be effective, but it largely depends on the target audience and brand personality. Overusing them can lead to deliverability issues. A/B testing is recommended to determine whether emojis improve or hinder performance.

December 2021 - Mailchimp
Marketer view

Email marketer from Campaign Monitor recommends that while emojis can add visual appeal, it is critical that they are relevant to your content. Overusing emojis may lead to lower deliverability rates due to being flagged by spam filters. Use them strategically and test with your audience.

December 2021 - Campaign Monitor
Marketer view

Email marketer from Email Geeks reminds users that emoji appearance varies across apps and operating systems, and some may not be universally supported.

June 2023 - Email Geeks
Marketer view

Email marketer from Mailjet shares that emojis can help your emails stand out, but it's important to use them strategically. Too many emojis can make your emails look spammy, which can hurt your sender reputation and deliverability. They suggest using them sparingly and ensuring they are relevant to your message.

May 2023 - Mailjet
Marketer view

Email marketer from Neil Patel's Blog shares that using emojis in subject lines can increase open rates because they stand out in the inbox, but overuse can make your email look like spam, negatively affecting deliverability. Test your audience to find the right amount.

July 2021 - Neil Patel's Blog
Marketer view

Email marketer from Quora responds with insights that emojis can catch the reader’s eye, increasing open rates. However, excessive use may cause your emails to be marked as spam, impacting deliverability negatively. Knowing your audience is key.

February 2025 - Quora
Marketer view

Email marketer from HubSpot Blog explains that while emojis can boost engagement, some mailbox providers may flag emails with excessive emojis as spam. Deliverability can suffer if spam filters are triggered. They recommend A/B testing to determine the impact on your audience.

January 2022 - HubSpot Blog
Marketer view

Email marketer from OptinMonster explains that emojis in subject lines can increase open rates and engagement but should be used sparingly and tested. Using too many can damage your sender reputation and negatively affect deliverability.

October 2022 - OptinMonster
Marketer view

Email marketer from EmailGeek Forums discusses that while emojis can increase open rates, it's essential to consider your target audience. Overusing them, especially in B2B communications, may lead to lower deliverability due to being flagged as spam.

April 2024 - EmailGeek Forums
Marketer view

Email marketer from Reddit in r/Emailmarketing shares from personal experience that emojis can work well, but it depends on the audience and brand. They suggest A/B testing with and without emojis to see what resonates best, but advise against using too many as it can look unprofessional.

March 2025 - Reddit

What the experts say
5Expert opinions

Experts generally agree that the impact of emojis on email deliverability is nuanced. Heavy use of emojis can be associated with spam and phishing, potentially harming sender reputation. However, a moderate approach, with one or two emojis, is often acceptable and even common. Cultural differences and audience demographics also play a significant role. Deliverability depends on various factors, not solely on the presence of emojis, and monitoring metrics is crucial.

Key opinions

  • Spam Association: Heavy emoji use is often linked to spam and phishing attempts.
  • Cultural Impact: Emoji meanings vary across cultures and age groups.
  • Moderate Use Accepted: Using one or two emojis is often acceptable and fairly common.
  • Holistic Analysis: Spam filters consider numerous email elements, not just emojis.

Key considerations

  • Sender Reputation: Maintain a good sender reputation, as it influences how emojis are perceived.
  • Audience Awareness: Understand your audience's preferences regarding emojis.
  • Monitoring Metrics: Track deliverability metrics to assess the impact of emojis on your campaigns.
  • Cultural Sensitivity: Be mindful of cultural interpretations of emojis.
  • Moderation: Avoid excessive emoji use; aim for a balanced approach.
Expert view

Expert from Email Geeks suggests avoiding all emojis, but notes that one or two are commonly used and that they recently received 25 out of 60 emails with emojis in the subject line.

May 2022 - Email Geeks
Expert view

Expert from Spamresource explains that subject line content, including the use of emojis, is one of many factors impacting deliverability. Spam filters analyze many elements of an email. They explain that using symbols or unusual characters can be a red flag, especially when combined with other factors that make an email appear suspicious.

May 2021 - Spamresource
Expert view

Expert from Email Geeks shares that heavy use of emojis in subject lines is often associated with spam and phishing attempts, advising caution when testing with important clients. Also mentions that brands do use a few emojis with no problems.

February 2023 - Email Geeks
Expert view

Expert from Email Geeks points out that the cultural meanings of emojis differ by location and age group.

March 2021 - Email Geeks
Expert view

Expert from Word to the Wise explains that using emojis in subject lines doesn't automatically trigger spam filters, but their impact depends on several factors, including sender reputation, audience engagement, and the content of the email. They advise monitoring your deliverability metrics when using emojis.

November 2023 - Word to the Wise

What the documentation says
4Technical articles

Email deliverability hinges on clear, concise, and relevant subject lines that avoid triggering spam filters. While not explicitly mentioning emojis, documentation from Gmail Help, Microsoft Support, Litmus, and SendGrid emphasizes the importance of avoiding poor formatting, misleading content, excessive symbols, and spam-like attributes. Maintaining a professional tone and consistent sender authentication is crucial for preserving domain reputation and ensuring emails reach their intended recipients.

Key findings

  • Clarity and Conciseness: Subject lines should be clear, concise, and accurately represent the email content.
  • Spam Trigger Avoidance: It is crucial to avoid anything that might trigger spam filters.
  • Subject Line Quality: Deliverability depends on subject line quality, including relevance and conciseness.
  • Symbol Usage: Excessive or misleading use of symbols can negatively affect deliverability.
  • Domain Reputation: Poor formatting and spam-like content impact domain reputation.

Key considerations

  • Professional Content: Email content should be professional and relevant.
  • Concise Subject Lines: Keep subject lines concise and engaging without appearing 'spammy'.
  • Sender Authentication: Ensure consistent sender authentication to maintain deliverability.
  • Relevance and Engagement: Subject lines must be engaging while remaining relevant to the email content.
  • Symbol Moderation: Be mindful of using symbols and avoid excessive or misleading implementation.
Technical article

Documentation from Microsoft Support details sender guidelines which, although not directly mentioning emojis, states that subject lines should be clear and represent the message's content accurately. Misleading or excessive use of symbols could negatively affect your sender reputation and deliverability.

November 2022 - Microsoft Support
Technical article

Documentation from SendGrid notes while discussing email design generally, that email content should be professional and relevant. Overusing emojis and symbols can affect deliverability by triggering spam filters. Consistent sender authentication helps maintain deliverability.

June 2022 - SendGrid
Technical article

Documentation from Gmail Help notes that while not explicitly mentioning emojis, using clear, concise subject lines and avoiding anything that might trigger spam filters is crucial for deliverability. Poor formatting or spam-like content in subject lines will affect your domain's reputation.

September 2024 - Gmail Help
Technical article

Documentation from Litmus explains that deliverability depends on various factors, including subject line quality. Using excessive or irrelevant characters/symbols can negatively impact deliverability by triggering spam filters. Subject lines must be concise, relevant and engaging without appearing 'spammy'.

March 2024 - Litmus