Summary
Including a plain text version of your HTML email is a multifaceted best practice. While its direct impact on deliverability for major B2C lists might be minimal, it significantly improves accessibility for users with visual impairments or older email clients. It also serves as a backup if HTML rendering fails. Although opinions vary on the strength of its deliverability influence, it's generally accepted that plain text versions can help sender reputation and avoid penalties from older spam filters. However, it is important to ensure that your email is also multipart/mime and that plain text is coded correctly to avoid issues like 'ALL CAPS' that may be incorrectly picked up as spam.
Key findings
- Accessibility: Plain text versions are crucial for users with visual impairments using screen readers, as well as those with older email clients or poor internet access.
- Deliverability (Indirect): While not a guaranteed direct boost, plain text can contribute to a better sender reputation and avoid issues with older spam filters. It also increases trust with ISPs.
- Backup Compatibility: Provides a fallback option if HTML rendering fails in the recipient's email client.
- Gmail Preferences: Gmail allows users to set a preference for plain text emails, making a plain text version important for those users.
- Potential Auto-generation Issues: Auto-generated plain text may contain formatting errors (like ALL CAPS) that can be flagged as spam.
- Mailbox protection: How many mailboxes are being protected can affect the need to have plain text or not. Larger mailbox services may use less aggressive strategies.
Key considerations
- Audience: Consider the needs of your audience, including accessibility requirements and their preferred email clients.
- List Size: Larger B2C lists on major providers might see less direct deliverability impact from plain text versions compared to smaller lists.
- Spam Filter Evolution: While older filters may penalize the absence of plain text, modern spam filters use more sophisticated methods.
- Code and Format: Ensure plain text is well-formatted and doesn't contain automatically generated formatting errors (e.g., ALL CAPS) that could trigger spam filters.
- Multipart MIME: Ensure emails are sent as multipart MIME to allow for both HTML and text to be sent at the same time.
- Benefits of text outweigh costs: Consider sending text as the cost is minimal but the benefits are high - particularly accessibility.
What email marketers say
8 marketer opinions
The inclusion of a plain text version of an HTML email is widely considered a best practice for email deliverability and accessibility. While some sources suggest it doesn't directly impact deliverability, it serves as a backup for older email clients or when HTML rendering fails. Additionally, providing a plain text version signals credibility to spam filters, aids in accessibility for users with visual impairments or poor internet access, and can improve sender reputation. However, auto-generated plain text versions may sometimes contain errors (like ALL CAPS) that can negatively affect deliverability.
Key opinions
- Accessibility: Plain text versions are essential for users with visual impairments who rely on screen readers, and for those with older email clients or limited internet access.
- Deliverability: While not always a direct factor, including a plain text version can improve sender reputation and signal credibility to spam filters, potentially boosting deliverability.
- Backup: Plain text versions act as a backup when HTML rendering fails, ensuring that the message is still accessible.
- Auto-generation Issues: Auto-generated plain text versions can sometimes contain errors (e.g., ALL CAPS from bold/strong tags) that may negatively impact deliverability.
Key considerations
- Accessibility needs: Consider the accessibility needs of your audience, especially those using screen readers or older email clients.
- Email client compatibility: Ensure that your emails are readable across a variety of email clients, including those that might not fully support HTML.
- Spam filter perception: Be mindful of how spam filters might perceive the absence of a plain text version.
- Auto-generation quality: If using auto-generation, check the plain text version for errors, particularly issues with formatting (e.g., ALL CAPS).
- Sender Reputation: Adding a plain text version of your emails can help improve your sender reputation.
Marketer view
Email marketer from HubSpot responds that having a plain text version of your HTML email is a key step in maintaining compliance with accessibility guidelines while also signaling credibility to spam filters. This shows you are offering options for your recipients to view your content.
13 Jul 2021 - HubSpot
Marketer view
Email marketer from Email on Acid shares that plain text emails are essential for accessibility, particularly for visually impaired users who may use screen readers. Providing a plain text version ensures that your message is understandable regardless of the recipient's abilities.
1 Jul 2022 - Email on Acid
What the experts say
7 expert opinions
The experts generally agree that while plain text versions might not be a major direct factor in deliverability for large B2C lists hosted by major providers, they are still valuable for several reasons. They can help avoid being penalized by older spam filters, contribute to a more positive sender reputation, and are crucial for accessibility. The importance is scaled by looking at what kind of list an organisation has with smaller lists being more susceptible to deliverability issues. However, for modern setups focusing on large providers, there is less evidence to support that they influence deliverability.
Key opinions
- Limited Direct Impact: For large B2C lists hosted by major providers (Google, Microsoft, Yahoo, etc.), lacking a plain text version is unlikely to significantly impact deliverability.
- Older Filters: Older spam filters may score emails without a plain text version as more spammy.
- Accessibility: Plain text versions are vital for accessibility, particularly for users needing screen readers.
- Sender Reputation: Providing both HTML and plain text versions contributes to a more positive sender reputation.
Key considerations
- List Size and Provider: Consider the size and hosting provider of your email list. Smaller lists and less common providers might benefit more from plain text versions.
- Aggressive Blocking: Understand that aggressive blocking strategies are harder to implement at scale, making plain text versions less critical for large lists.
- Spam Filter Evolution: Recognize that modern spam filters are becoming more sophisticated, potentially reducing the impact of simply having a plain text version.
- Accessibility Needs: Prioritize accessibility by including plain text versions, particularly for users with disabilities.
- Text/html vs multipart/mime: Be aware of whether you are already sending text/html rather than multipart/mime as this can influence deliverability.
Expert view
Expert from Email Geeks shares that they still add a text version because some older filters score you as slightly more spammy if you only have an HTML version.
4 May 2024 - Email Geeks
Expert view
Expert from Email Geeks says while advising folks to include plain text versions, it's challenging to give good reasons if they are already sending text/html rather than multipart/mime.
13 Nov 2022 - Email Geeks
What the documentation says
3 technical articles
Email documentation from Google, Microsoft and RFC 2822 emphasize that plain text is important for accessibility and compatibility. While not explicitly mandated as a deliverability requirement, providing a plain text version ensures that the email can be rendered across different platforms, by various email clients including Gmail which can be set to always prefer the text only version, and also improves accessibility which is good practice.
Key findings
- Platform Rendering: Including a plain text version helps ensure your email renders correctly across different platforms.
- Accessibility Focus: Documentation stresses the importance of accessibility, which plain text versions directly support.
- Gmail Preference: Gmail can display either the HTML or plain text version based on the recipient's settings, highlighting the need to provide both.
- Standards Compliance: While not a mandate, adhering to the 'spirit' of Internet message format standards (like RFC 2822) includes considering compatibility and accessibility via plain text.
Key considerations
- Audience Preferences: Be aware that some recipients may prefer plain text emails, and provide a way to cater to these preferences.
- Accessibility Standards: Prioritize email accessibility to ensure inclusivity and broaden your reach.
- Email Client Compatibility: Account for the variety of email clients and platforms your recipients might use, including older ones that may handle HTML poorly.
- Deliverability Influence: While not a guaranteed fix, recognize that including plain text *can* positively influence deliverability.
Technical article
Documentation from Microsoft suggests that including a plain text version can positively influence your email deliverability. It helps to ensure that your email renders correctly across different platforms, and improves accessibility.
10 Jul 2024 - Microsoft
Technical article
Documentation from RFC 2822 (Internet Message Format) specifies the standards for email messages, including the structure of headers and body. While it doesn't explicitly mandate plain text, it emphasizes the importance of compatibility and accessibility, which plain text versions contribute to.
31 Jul 2024 - RFC 2822
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