Summary
The consensus is that using bold text sparingly in emails is unlikely to directly and negatively impact deliverability. While excessive HTML formatting, including bolding, can contribute to a higher spam score if it's part of a pattern of behaviors associated with spam, the key determinants for deliverability are sender reputation, authentication (SPF, DKIM, DMARC), list hygiene, content quality, and clean HTML coding practices. Some data suggests older audiences respond positively to bolded text. A/B testing is recommended to understand audience-specific impacts. Clean HTML and avoiding spam trigger words are key to avoiding spam filters.
Key findings
- Minimal Direct Impact: Using bold text sparingly does not directly trigger spam filters.
- Poor Code, Indirect Impact: Poor HTML practices and excessive styling associated with bolding can negatively impact deliverability.
- Key Deliverability Factors: Sender reputation, authentication (SPF, DKIM, DMARC), list hygiene, and engaging content are paramount.
- Older Audiences Respond Well: Some data suggests older audiences respond well to heavily bolded content.
- Context Matters: Excessive formatting raises red flags when combined with other spammy characteristics.
Key considerations
- Use Sparingly: Use bold text judiciously for emphasis, avoiding overuse.
- Clean Code: Maintain clean, well-structured HTML code, minimizing complexity.
- Authenticate: Implement SPF, DKIM, and DMARC for email authentication.
- List Hygiene: Maintain a clean and engaged subscriber list.
- Valuable Content: Prioritize high-quality, relevant content.
- A/B Test: Consider A/B testing to optimize formatting and content.
- Well Formed Emails: Ensure emails are well-formed and do not contain malformed markup.
What email marketers say
12 marketer opinions
While excessive bold text was once considered a potential spam trigger, current consensus suggests that using bold text sparingly for emphasis in emails does not significantly impact deliverability on its own. Deliverability is more heavily influenced by factors like sender reputation, authentication (SPF, DKIM, DMARC), list hygiene, content quality, and clean HTML coding practices. Poor coding practices associated with excessive styling (including bolding) can indirectly affect deliverability. Some suggest A/B testing to determine the impact on engagement.
Key opinions
- Limited Impact of Bold Text: Using bold text sparingly is unlikely to directly trigger spam filters.
- Importance of Clean Code: Poor coding practices, including excessive styling, can negatively affect deliverability.
- Key Deliverability Factors: Sender reputation, authentication, list hygiene, and content quality are more critical for deliverability.
- A/B Testing Recommendation: A/B testing can help determine the impact of formatting on deliverability and engagement.
- Older Audience: Older audiences have been observed to respond positively to heavily bolded emails.
Key considerations
- Use Bold Text Judiciously: Use bold text sparingly for emphasis rather than for large blocks of text.
- Maintain Clean HTML: Ensure your email HTML code is clean, well-structured, and avoids unnecessary complexity.
- Authenticate Your Emails: Properly configure SPF, DKIM, and DMARC to improve sender reputation.
- Practice List Hygiene: Maintain a clean and engaged email list to avoid spam complaints.
- Focus on Valuable Content: Create high-quality, relevant content that resonates with your audience.
- Consider Audience Demographics: Take into account audience demographics and adjust design elements accordingly.
Marketer view
Email marketer from Mailjet Blog explains that using bold text sparingly in emails is unlikely to significantly impact deliverability. However, excessive or improper use of HTML tags, including bold tags, can contribute to increased email size and potentially trigger spam filters. They recommend focusing on providing valuable content and ensuring proper HTML structure.
15 Sep 2023 - Mailjet Blog
Marketer view
Marketer from Email Geeks and Dusty Werner discuss how older audiences had a good response to a very bolded email. Johan mentions could test a slightly heavier font weight and Pixel size, font weight, line height etc. You could even track this against a user profile and personalise accordingly.
26 Dec 2023 - Email Geeks
What the experts say
1 expert opinions
Excessive HTML formatting, including bold text, might contribute to a higher spam score if it aligns with spammy patterns. Bold text alone isn't a direct trigger, but it can raise flags when combined with other characteristics associated with spam emails.
Key opinions
- Combined Factors Matter: Bold text is not a definitive spam trigger on its own.
- Pattern Recognition: Spam filters look for patterns of behavior, including excessive formatting.
- Increased Spam Score: Excessive use of HTML formatting can contribute to a higher spam score when combined with other potentially problematic elements.
Key considerations
- Avoid Overuse: Limit the use of excessive HTML formatting, including bold text.
- Review Email Content: Ensure your email doesn't contain other elements that could be flagged as spammy.
- Focus on Best Practices: Adhere to general email marketing best practices to minimize the risk of being marked as spam.
Expert view
Expert from Word to the Wise explains that excessive use of HTML formatting, including bold text, can contribute to a higher spam score if it's part of a pattern of behaviors associated with spam. While bold text alone isn't a definitive trigger, it could raise flags if combined with other spammy characteristics in the email.
27 Jul 2021 - Word to the Wise
What the documentation says
6 technical articles
Email deliverability is generally unaffected by the use of bold text, however documentation advises that clean HTML and avoiding spam trigger words, alongside authenticating your domain is key to avoiding spam filters. Focus should be placed on best practices such as sender authentication, sender reputation and content relevance. Excessive HTML formatting may increase email size and trigger spam filters.
Key findings
- Best Practices: Focus should be placed on best practices such as sender authentication, sender reputation and content relevance.
- Clean HTML: Clean HTML and avoiding spam trigger words is key to avoiding spam filters.
- Excessive HTML Formatting: Excessive HTML formatting may increase email size and trigger spam filters.
- Semantic HTML: Emphasis on using semantic HTML and CSS for styling.
Key considerations
- Ensure HTML emails are well-formed: Ensure HTML emails are well-formed and that they do not contain excessive or malformed markup.
- Create engaging content: Focus on creating engaging content and optimizing images for better deliverability.
- Domain Authentication: Authenticate your domain.
Technical article
Documentation from Google prioritizes authentication (SPF, DKIM, DMARC), avoiding sending unwanted mail, and making it easy for recipients to unsubscribe. The use of bold text is not specified as a potential spam trigger.
29 Jul 2022 - Google
Technical article
Documentation from Mailchimp advises that focusing on creating clean HTML and avoiding spam trigger words, alongside authenticating your domain, is key to avoiding spam filters; bold text alone should not trigger spam filters.
8 Nov 2022 - Mailchimp
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