Does including a plain text version of an email improve deliverability and conversion rates?

Summary

Including a plain text version alongside HTML offers a multifaceted approach to email deliverability and user experience. While its direct impact on deliverability may be subtle, plain text enhances accessibility for users with disabilities or those using text-based clients and acts as a fallback when HTML rendering fails. It can potentially bypass spam filters and improve sender reputation due to its cleaner structure and reduced complexity. Furthermore, plain text offers a more secure alternative due to the absence of executable code, and its simplicity can create a more personal connection. However, it lacks tracking capabilities and requires careful A/B testing to determine the optimal format for specific audiences. Maintaining consistent content between HTML and plain text versions is crucial, and understanding how tracking links are handled is essential for analyzing campaign performance. Analyzing conversion discrepancies across different ISPs can further refine email strategies.

Key findings

  • Enhanced Accessibility and Fallback: Plain text ensures readability for all users, especially when HTML rendering fails or for those with accessibility needs.
  • Potential Deliverability Benefits: It may improve deliverability by bypassing spam filters and enhancing sender reputation.
  • Improved Security: Plain text is more secure due to the absence of executable code.
  • Simplified, Personal Connection: It can foster a more personal connection with recipients.

Key considerations

  • Lack of Tracking Capabilities: Plain text lacks tracking features, impacting marketing insights.
  • Importance of A/B Testing: A/B testing is necessary to determine the optimal format for specific audiences and goals.
  • Content Consistency: Maintaining consistent content between HTML and plain text versions is essential.
  • Tracking Link Analysis: Understanding how tracking links are handled is critical for accurate campaign performance analysis.
  • ISP-Specific Analysis: Analyzing conversion discrepancies across different ISPs can optimize email strategies.
  • Plain Text Limitations: Keep in mind there is only line break and tab support in plain text.

What email marketers say
14Marketer opinions

Including a plain text version of an email alongside HTML offers several potential benefits, although its direct impact can vary. It enhances accessibility, ensures readability when HTML rendering fails, and may help bypass spam filters due to its cleaner structure. Some suggest plain text can also provide a more personal feel and avoid tracking, while others point out its lack of tracking capabilities as a drawback. A/B testing is recommended to determine the optimal format for a specific audience, with careful consideration of rendering issues and mailbox provider-specific problems. Ultimately, plain text acts as a safety net, improving the overall user experience and potentially boosting deliverability, especially when HTML presents rendering issues.

Key opinions

  • Accessibility & Readability: Plain text ensures readability when HTML rendering fails or for users who prefer it, enhancing accessibility.
  • Spam Filtering: Plain text versions may help in bypassing spam filters due to their simpler structure.
  • HTML Rendering Issues: If plain text has a higher conversion rate, it indicates potential HTML rendering issues with specific providers.
  • Sender Reputation: Including plain text helps improve sender reputation and reduces the likelihood of being flagged as spam.
  • Personalization: Plain text emails have a more personal feel and can circumvent tracking methods.

Key considerations

  • Lack of Tracking: Plain text emails lack tracking capabilities for opens and clicks, affecting marketing insights.
  • A/B Testing: A/B testing HTML and plain text versions is recommended to determine the best format for your audience.
  • Consistent Content: Plain text versions should contain the same information and CTAs as the HTML version.
  • Domain Tracking: Check links use the sender's domain and the HTML is original and rendering properly, to look for patterns in split tests related to mailbox providers or email clients.
  • Rendering Issues: Break down conversions by mailbox provider to see if a particular provider is having problems with the HTML.
Marketer view

Email marketer from SuperOffice explains that a plain text version should contain the same information as the HTML version, including the key call-to-actions. This ensures that all recipients have access to the core content, regardless of how they view the email.

November 2021 - SuperOffice
Marketer view

Email marketer from Stack Overflow answers that providing a plain text version alongside HTML can potentially lower spam scores, as some spam filters penalize emails that only contain HTML. However some users believe there is no evidence to support this.

March 2025 - Stack Overflow
Marketer view

Marketer from Email Geeks suggests if the links use the sender's domain and the HTML is original and rendering properly, to look for patterns in split tests related to mailbox providers or email clients.

February 2023 - Email Geeks
Marketer view

Email marketer from Sendinblue shares that providing a plain text version alongside HTML enhances accessibility and can improve deliverability, as some recipients may prefer or require plain text emails.

March 2022 - Sendinblue
Marketer view

Email marketer from Reddit shares that a well-formatted plain text version acts as a safety net. While modern email clients primarily display HTML, the presence of plain text ensures readability if HTML rendering fails, positively impacting deliverability.

June 2021 - Reddit
Marketer view

Email marketer from HubSpot suggests A/B testing both HTML and plain text versions of emails to determine which format yields better conversion rates with a specific audience. The best option will depend on the demographic you are targeting.

December 2023 - HubSpot
Marketer view

Marketer from Email Geeks suggests breaking down conversions by mailbox provider (e.g., Gmail, AOL) to identify if a particular provider is having problems with the HTML.

September 2021 - Email Geeks
Marketer view

Email marketer from Campaign Monitor explains that while the direct impact may be minimal for most users, providing a plain text version can contribute to a cleaner email structure, potentially improving sender reputation and reducing the likelihood of being flagged as spam.

September 2021 - Campaign Monitor
Marketer view

Email marketer from Mailjet explains that plain text versions are crucial for bypassing spam filters, as they provide a cleaner, less complex version of the email that's easier for filters to scan and trust.

October 2023 - Mailjet
Marketer view

Email marketer from ActiveCampaign explains that one downside to plain text emails is that they lack the ability to track opens and clicks, which can affect the marketing insights obtained from a campaign. There is no option to track engagement.

July 2021 - ActiveCampaign
Marketer view

Email marketer from Gmass shares that plain text emails often have a more personal feel and can circumvent sophisticated email tracking methods employed in HTML emails, enhancing privacy for the recipient.

April 2022 - Gmass
Marketer view

Email marketer from Email on Acid responds that including a plain text version ensures that your message is readable even if the HTML version doesn't render correctly in certain email clients, preventing loss of communication.

May 2022 - Email on Acid
Marketer view

Marketer from Email Geeks shares that a plain text message removes many potential issues that filters might find problematic, so including one won't hurt deliverability.

August 2022 - Email Geeks
Marketer view

Marketer from Email Geeks suggests that if only the plain text version is seeing a lift in conversions, there might be a rendering issue with the HTML version.

July 2024 - Email Geeks

What the experts say
5Expert opinions

Including a plain text version of an email may not directly and noticeably affect deliverability. However, it ensures accessibility and readability for recipients who prefer or require plain text, potentially improving user experience and indirectly impacting mailstream reputation. A large difference in conversion rates between HTML and plain text versions warrants further investigation, specifically checking for consistency across different recipient ISPs. Additionally, understanding the behavior of tracking links (whether they point to the sender's domain and if the ESP rewrites them) is important. Note plain text supports only limited formatting - line breaks and tabs.

Key opinions

  • Limited Direct Impact on Deliverability: A plain text version likely won't have a significant direct impact on deliverability.
  • Enhanced Accessibility: It ensures readability for recipients who prefer or require plain text.
  • Indirect Impact via User Experience: Improved user experience can indirectly affect the reputation of the mailstream.
  • Limited Formatting: Plain text supports only line breaks and tabs.

Key considerations

  • Analyze Conversion Discrepancies: Investigate inconsistencies in conversion rates between HTML and plain text versions, checking across different ISPs.
  • Track Link Behavior: Understand how tracking links are handled (domain, rewriting by ESP).
Expert view

Expert from Email Geeks asks if the tracking links point to the sender's domain or a different domain (possibly shared by the ESP) and if the ESP is rewriting the links for click tracking, as this is important information.

July 2022 - Email Geeks
Expert view

Expert from Word to the Wise explains that including a plain text version ensures that recipients who prefer or require it (due to disabilities or email client limitations) can still read your message, which improves accessibility and overall user experience.

September 2024 - Word to the Wise
Expert view

Expert from Email Geeks advises digging deeper into the data if there is a large difference in conversion rates, and start by checking if the difference is consistent across different recipient ISPs.

May 2024 - Email Geeks
Expert view

Expert from Email Geeks explains that the existence of a well-formed plain text email probably won't affect deliverability directly in a noticeable way. However, it may affect user experience for recipients who read plain text, and their engagement might indirectly affect the overall reputation of your mailstream.

August 2021 - Email Geeks
Expert view

Expert from Word to the Wise responds that plain text email has very little formatting - only line breaks and tabs.

July 2021 - Word to the Wise

What the documentation says
4Technical articles

Including a plain text version alongside HTML in email messages ensures broader compatibility and accessibility. The RFC standards specify that plain text serves as a fallback for HTML, guaranteeing readability across different email clients. Litmus highlights that this practice enhances accessibility for users with disabilities and those using text-based clients, improving overall user experience. Additionally, MDN Web Docs points out that plain text emails are inherently more secure due to the absence of executable code. Microsoft Support emphasizes that providing both formats allows email clients like Outlook to display messages according to the recipient's preferences.

Key findings

  • Fallback Readability: Plain text serves as a fallback, ensuring messages are readable across all email clients.
  • Enhanced Accessibility: Plain text improves accessibility for users with disabilities or text-based email clients.
  • Improved Security: Plain text emails are more secure due to the lack of executable code.
  • Client Preference Support: Providing both formats allows email clients to display messages according to user preferences.

Key considerations

Technical article

Documentation from Litmus explains that providing a plain text version makes emails more accessible to users with disabilities or those using text-based email clients, improving the overall user experience.

December 2024 - Litmus
Technical article

Documentation from RFC 5322 specifies the standards for email message formats, including multipart messages, where a plain text version serves as a fallback for HTML, ensuring readability across different email clients.

May 2021 - RFC 5322
Technical article

Documentation from Microsoft Support clarifies that Outlook provides options for users to select their preferred email format. Providing both HTML and plain text versions ensures that messages are displayed according to the recipient's settings.

March 2024 - Microsoft Support
Technical article

Documentation from MDN Web Docs explains that in terms of security, plain text emails are inherently less risky than HTML emails due to the absence of executable code (like JavaScript) that could be exploited for malicious purposes.

July 2024 - MDN Web Docs