Will using non-breaking spaces and soft hyphens in email templates affect inbox placement?

Summary

The impact of non-breaking spaces ( ) and soft hyphens (­) on email inbox placement is complex. While using them for preheader padding may not be penalized, excessive or manipulative use is problematic. Key concerns include increased email size, triggering spam filters due to bloated or hidden code, and deviating from modern CSS-based layout practices. Clean, semantic HTML is crucial. Testing across clients is vital, and maintaining a good sender reputation remains paramount.

Key findings

  • Preheader Padding OK: Using   for preheader padding is common and not usually penalized.
  • Excessive Use Bad: Overuse of   and ­ increases email size and can trigger spam filters.
  • Hidden Code Suspect: Using these characters to hide content raises red flags with spam filters.
  • Modern CSS Preferred: Modern email development favors CSS for layout over  .
  • Clean Code Crucial: Clean, well-structured HTML is vital for consistent rendering and deliverability.
  • Reputation Matters: Sender reputation and email content are primary factors for avoiding spam filters.

Key considerations

  • Code Efficiently: Prioritize clean, semantic HTML and CSS to minimize email size.
  • Use CSS for Layout: Employ modern CSS techniques for spacing and layout.
  • Be Judicious: Use   and ­ sparingly and only when necessary.
  • Test Thoroughly: Test emails across clients to ensure proper rendering and identify issues.
  • Reputation First: Focus on building and maintaining a positive sender reputation.
  • Check Content Quality: Ensure email content is relevant, engaging, and avoids spam triggers.

What email marketers say
9Marketer opinions

The impact of using non-breaking spaces ( ) and soft hyphens (­) on email inbox placement is nuanced. While judicious use is unlikely to cause significant harm, excessive use or using these characters in a way that seems like an attempt to manipulate content can negatively affect deliverability. Key issues include increased email size, potentially triggering spam filters due to bloated or hidden code, and deviating from modern coding practices that favor CSS for layout. Modern coding should be considered, keeping email size minimum and semantic HTML.

Key opinions

  • Excessive Use: Overusing   and ­ can increase email size, potentially leading to deliverability issues.
  • Spam Triggers: Unnecessary HTML, including unusual character entities, can trigger spam filters.
  • Hidden Code: Using these characters for hidden preheader text or other manipulative purposes is likely to be flagged as suspicious.
  • Modern Practices: Modern email development emphasizes using CSS for layout instead of relying on  .
  • Alternative Factors: There are likely other factors with a higher weighting, like the sender's reputation, content, and images.

Key considerations

  • Code Efficiency: Prioritize clean, semantic HTML and CSS to minimize email size and improve rendering across different email clients.
  • Modern Coding: Use modern CSS for spacing and layout instead of relying on non-breaking spaces.
  • Judicious Use: If using   or ­, do so sparingly and only when necessary.
  • Test Thoroughly: Test email templates across various email clients and devices to ensure proper rendering and avoid unexpected issues.
  • Sender Reputation: Ensure the sender has a good reputation by validating IP and domain using SPF, DKIM, and DMARC standards.
Marketer view

Email marketer from HubSpot responds that bloated HTML code in emails will impact deliverability, and to keep your HTML code clean and minimal to reduce the chances of emails being marked as spam.

May 2021 - HubSpot
Marketer view

Email marketer from Mailjet Blog explains that while non-breaking spaces ( ) were previously used for layout purposes, modern CSS should be used instead. Overuse of   can increase email size and potentially affect deliverability.

October 2022 - Mailjet Blog
Marketer view

Email marketer from Reddit responds that hidden code (often using zero-width spaces or similar techniques) used excessively for preheader text or other purposes, can sometimes be flagged as suspicious by spam filters, especially if it's perceived as an attempt to manipulate content.

February 2025 - Reddit
Marketer view

Email marketer from EmailGeek forum user shares that in their experience, the _judicious_ use of either   or ­ is unlikely to dramatically impact deliverability, though excessive usage could increase the spam score due to increased email size and the potential for it to be flagged as an attempt to hide content.

January 2023 - EmailGeek Community
Marketer view

Email marketer from Email on Acid Blog shares that excessive or unnecessary HTML code, including unusual character entities, can trigger spam filters. Clean, semantic code is always preferable.

April 2021 - Email on Acid Blog
Marketer view

Email marketer from Stack Overflow suggests that using too many non-breaking spaces ( ) can increase the size of the email, which might affect deliverability negatively. The user advises using CSS for spacing instead.

December 2023 - Stack Overflow
Marketer view

Email marketer from Gmass shares that non-breaking spaces are likely not going to cause emails to go to spam filters. However, it is more likely that images with no alt text and URL shorteners will affect inbox placement.

May 2023 - Gmass
Marketer view

Email marketer from Sendinblue shares multiple factors that will affect email deliverability. One of these is using valid HTML, so make sure that the email is not bloated with unnecessary code.

August 2021 - Sendinblue
Marketer view

Email marketer from ActiveCampaign explains the importance of using valid HTML in order to improve email deliverability and to avoid spam filters. Therefore, it is best practice to avoid unnecessary and bloated HTML.

August 2021 - ActiveCampaign

What the experts say
4Expert opinions

The consensus is nuanced. Non-breaking spaces are frequently used for preheader padding, and mailbox providers generally don't penalize this. However, excessive use of these characters or other 'character stuffing' techniques to manipulate content or bypass filters can negatively impact deliverability and sender reputation. Pre-header hiding code should be tested, as issues can arise in how it's rendered by certain providers. Keeping code clean and efficient is always recommended.

Key opinions

  • Preheader Padding: Non-breaking spaces are often used for preheader padding and are generally not penalized by mailbox providers.
  • Character Stuffing: Excessive use of characters, including non-breaking spaces, to manipulate content or bypass filters harms deliverability and sender reputation.
  • Rendering Issues: Pre-header hiding code can sometimes render unexpectedly, such as showing as a row of boxes.
  • Code Quality: Improper or unnecessary HTML coding can lead to rendering issues and trigger spam filters.

Key considerations

  • Testing: Test pre-header hiding code across different email clients (e.g., Gmail, Apple Mail) to ensure proper rendering.
  • Code Efficiency: Prioritize clean and efficient HTML coding to avoid triggering spam filters and ensure proper rendering.
  • Judicious Use: Use non-breaking spaces and other similar characters sparingly to avoid being flagged for character stuffing.
  • Content Manipulation: Avoid using techniques to manipulate email content, as this can negatively impact your sender reputation.
Expert view

Expert from Email Geeks explains that the code is regular padding to shove the non “preheader” content out of the way and mailbox providers won’t care.

November 2022 - Email Geeks
Expert view

Expert from Email Geeks shares that it's pre-header hiding code and to test it in Gmail web and Apple Mail as sometimes some versions of the code will show up. Potentially as a row of little boxes in the preheader area, not leaking into the body.

October 2021 - Email Geeks
Expert view

Expert from Word to the Wise shares that improper or unnecessary HTML coding can lead to rendering issues and potentially trigger spam filters. While not directly addressing non-breaking spaces and soft hyphens, the site suggests keeping email code clean and efficient.

November 2024 - Word to the Wise
Expert view

Expert from SpamResource explains that 'character stuffing,' which involves adding excessive or meaningless characters (including non-breaking spaces) to manipulate content or bypass filters, negatively impacts deliverability and sender reputation.

July 2023 - SpamResource

What the documentation says
4Technical articles

The documentation suggests that while soft hyphens provide layout suggestions, the ultimate rendering depends on the browser. Clean, well-structured HTML is essential for consistent rendering and avoiding deliverability issues. Although   and ­ are not specifically mentioned in most of the documentation, excessive or bad code can negatively impact deliverability and sender reputation. Sender reputation and the email content are key to avoiding junk mail folders.

Key findings

  • Clean Code: Clean, well-structured HTML code is crucial for consistent email rendering across different clients.
  • Code Quality Impact: Bad or excessive code can negatively affect email deliverability.
  • Soft Hyphen Rendering: The rendering of soft hyphens depends on the browser's layout algorithm, affecting user experience.
  • Key Deliverability Factors: Sender reputation and email content are critical factors influencing whether emails land in the junk folder.

Key considerations

  • Semantic HTML: Focus on using semantic HTML to create a well-structured email template.
  • Code Minimization: Avoid unnecessary code to prevent deliverability issues.
  • Browser Compatibility: Consider how different browsers render soft hyphens and test accordingly.
  • Reputation and Content: Maintain a good sender reputation and ensure your email content is high-quality to avoid spam filters.
Technical article

Documentation from Litmus explains that using clean, well-structured HTML code in your email templates is crucial for consistent rendering across different email clients. Avoid unnecessary code and focus on semantic HTML.

April 2021 - Litmus
Technical article

Documentation from Microsoft addresses junk email and spam filters, and although it doesn't directly mention   or ­ it does provide information on factors that contribute to emails landing in the junk folder. One factor is the sender's reputation. Another factor is the content of the email.

February 2023 - Microsoft Support
Technical article

Documentation from MDN Web Docs explains that the soft hyphen (­) element is a suggestion to the browser where to break a word in order to improve layout. Whether or not the hyphen is visible depends on the browser's layout algorithm. While not directly related to deliverability, unexpected rendering could impact user experience.

July 2021 - MDN Web Docs
Technical article

Documentation from Campaign Monitor responds that bad or excessive code can affect deliverability. While they do not specifically mention   or soft hyphens, they do suggest keeping your code clean and using modern standards.

September 2023 - Campaign Monitor