- \n
- Tables > fancy CSS<\/li>\n\n\n\n
- Inline CSS only<\/li>\n\n\n\n
- Single-column, 600px max width<\/li>\n\n\n\n
- Mobile-first, big text, big buttons<\/li>\n\n\n\n
- Copy works without images<\/li>\n\n\n\n
- Safe fonts with fallback<\/li>\n\n\n\n
- Alt text + accessibility tags<\/li>\n\n\n\n
- Unsubscribe clearly visible<\/li>\n\n\n\n
- Email copy tested across Gmail, Outlook, Apple Mail<\/li>\n<\/ul>\n\n\n\n
For details information on this, you can skip to the HTML best practices directly from here.<\/p>\n\n\n\n
What are the most common HTML issues related to emails?<\/strong><\/h2>\n\n\n\n
The most common HTML issues in emails often come from poor coding practices or using design tools that generate bloated code. These include:<\/p>\n\n\n\n
- \n
- Unclosed tags<\/strong> \u2013 Leaving <table>, <tr>, or <td> tags unclosed can break rendering.<\/li>\n\n\n\n
- Too many nested tables<\/strong> \u2013 While tables are common in email design, excessive nesting makes code heavy and harder for clients to render.<\/li>\n\n\n\n
- Inline styles with unsupported properties<\/strong> \u2013 Some email clients ignore certain CSS properties, causing layout issues.<\/li>\n\n\n\n
- External CSS or JavaScript<\/strong> \u2013 Most email clients strip these out, leading to broken designs.<\/li>\n\n\n\n
- Large images without alt text<\/strong> \u2013 Not only impacts accessibility but also spam filter trust.<\/li>\n\n\n\n
- Using non-standard fonts without fallback<\/strong><\/li>\n\n\n\n
- Copy-pasted code from Word or Google Docs<\/strong> \u2013 Often contains unnecessary formatting tags that trigger spam filters<\/a>.<\/li>\n<\/ul>\n\n\n\n
Identifying and fixing these issues before sending ensures your email looks correct and avoids spam flags.<\/p>\n\n\n\n
Why do the HTML issues in emails push emails to spam?<\/strong><\/h2>\n\n\n\n
HTML problems push emails into spam because email spam filters look for patterns that match suspicious or sloppy coding. <\/p>\n\n\n\n
If your HTML email copy contains unnecessary tags, outdated attributes, or code copied directly from Word or design tools, it can appear similar to phishing or spam emails<\/em><\/strong>.<\/p>\n\n\n\n
Email service providers like Gmail, Yahoo, Outlook etc. scan your HTML version before showing it to recipients. <\/p>\n\n\n\n
If your code is bloated, broken, or contains non-standard practices, it can trigger filters. For example:<\/p>\n\n\n\n
- \n
- Broken HTML tags<\/strong> can stop an email from rendering properly.<\/li>\n\n\n\n
- Excessive CSS or inline styles<\/strong> may resemble spammy design patterns.<\/li>\n\n\n\n
- Missing plain-text versions<\/strong> make emails look suspicious to email security systems.<\/li>\n<\/ul>\n\n\n\n
Even if your email subject line <\/a>and content are clean, HTML rendering issues can affect trust signals and domain reputation, making it more likely that your emails land in the spam folder.
<\/p>\n\n\n\nHow to create HTML emails for better deliverability and responses?<\/strong><\/h2>\n\n\n\n
Here are some best practices you can follow while setting up your HTML emails for the best email deliverability<\/a>.\u00a0<\/p>\n\n\n\n
Note: <\/strong>These tips are more suitable for <\/em>email marketing<\/em><\/strong> than cold emails. For cold emails, it\u2019s always recommended to use clean text based emails for the the maximum deliverability and responses. <\/em><\/p>\n\n\n\n
Tip #1. Use table layouts in the email<\/strong><\/h3>\n\n\n\n
Don\u2019t get fancy with CSS grids or flexbox. Most email apps can\u2019t handle them well.\u00a0<\/p>\n\n\n\n
![\"example](\"https:\/\/smartreach.io\/blog\/wp-content\/uploads\/2025\/08\/AD_4nXdRQCcCLEuCuiAFCnr9aO6OLIrkQX3jp1f-YYp6Xuiezav3hNOqSAGW6cHjn5Wtu7rq8UxPIxPKXYv2ylugZje3RrRBiSFIAYCFZcxuGELGHv7Pk424xvBbqO0NtAiIzIAdNqU0.png\")
<\/figure>\n\n\n\n*example of a HTML email template in the table layout style<\/em><\/p>\n\n\n\n
Stick to basic table layouts, they look boring in code but guarantee your design won\u2019t break in Gmail or Outlook.<\/p>\n\n\n\n
Tip #2. Keep the code simple<\/strong><\/h3>\n\n\n\n
Every extra layer of styling increases the risk of something breaking. <\/p>\n\n\n\n
Use inline CSS only<\/em><\/strong>, and keep your HTML lean. <\/p>\n\n\n\n
A clutter-free template loads faster and is less likely to be flagged as \u201csuspicious.\u201d
<\/p>\n\n\n\nTip #3. Design for mobile first<\/strong><\/h3>\n\n\n\n
More than half of emails get opened on mobile. <\/p>\n\n\n\n
Start with a single-column design, large fonts (14\u201316px), and buttons that are big enough for thumbs. <\/p>\n\n\n\n
If it looks great on mobile, it\u2019ll hold up on desktop too.<\/strong>
<\/p>\n\n\n\nTip #4. Limit image dependence in the copy<\/strong><\/h3>\n\n\n\n
Email providers often block images by default. So:<\/p>\n\n\n\n
- \n
- Write HTML copy that makes sense even without pictures<\/li>\n\n\n\n
- Add alt text<\/strong> so if the image doesn\u2019t load, the message still comes across.<\/li>\n\n\n\n
- Never send image-only emails. They\u2019re almost guaranteed to land in spam.<\/li>\n<\/ul>\n\n\n\n
For more details image usage on emails, check out our detailed guide \u201cHow to Balance Images and Text to Keep Emails Out of Spam?<\/em><\/strong><\/a>\u201d<\/p>\n\n\n\n
Tip #5. Stick to safe fonts<\/strong><\/h3>\n\n\n\n
Custom fonts look stylish, but they won\u2019t render everywhere. <\/p>\n\n\n\n
Stick to basics like Arial, Georgia, or Verdana<\/strong>. If you must use a custom font, always add a fallback option.<\/p>\n\n\n\n
Tip #6. Focus on email accessibility<\/strong><\/h3>\n\n\n\n
Use proper headings (<h1>, <h2>), good color contrast, and descriptive alt text. Accessibility helps users and improves email deliverability too.<\/p>\n\n\n\n
Tip #7. Make unsubscribing easy for emails<\/strong><\/h3>\n\n\n\n
It may feel counterintuitive, but a clear unsubscribe link actually protects your sender reputation. <\/p>\n\n\n\n
![\"Example](\"https:\/\/smartreach.io\/blog\/wp-content\/uploads\/2025\/08\/AD_4nXd1hBJWKWaYmxX6NcQ-qx4uGj00sR6-nBrZ21L1L6K0Uf8yfhBbCD3hMRYAfenjzUFehiEtdrWW7VWmiI2ipATM9tbZNa7RyoATLFpZyhWLZ8pRwIbyKWfWCemj3siQ5gug5XwSxA.png\")
<\/figure>\n\n\n\nImage credit<\/a><\/p>\n\n\n\n
If people can\u2019t find it, they\u2019ll just hit \u201cMark as Spam<\/strong>,\u201d which hurts your email deliverability in the long run.<\/p>\n\n\n\n
Read more: How to Prevent Recipients from Marking Emails as Spam?<\/em><\/strong><\/a><\/p>\n\n\n\n
Tip #8. Always test the email copy before sending<\/strong><\/h3>\n\n\n\n
Your email won\u2019t look the same in Gmail, Outlook, and Apple Mail. Always test in multiple inboxes before blasting it.<\/p>\n\n\n\n
Also, run spam filter checks with tools like Mail-Tester<\/a> for free.\u00a0<\/p>\n\n\n\n
Conclusion<\/strong><\/h2>\n\n\n\n
HTML emails work the best when the designs are minimal. <\/p>\n\n\n\n
So, follow all the best practices mentioned above while creating these emails.<\/p>\n\n\n\n
HTML emails works best for the marketing emails such as product updates, feature launches etc.<\/p>\n\n\n\n
If you are sending cold emails, avoid using an HTML copy and use a 100% text based email copy instead.<\/strong><\/p>\n\n\n\n
They offer the best deliverability with the higher likelihood of responses from the recipients.<\/p>\n\n\n\n
Use an email automation platform like SmartReach.io<\/a>.
It has built-in email deliverability tools that protect your cold emails from spam risks and fetch the maximum ROI out of your cold email campaigns.<\/p>\n\n\n\n - Never send image-only emails. They\u2019re almost guaranteed to land in spam.<\/li>\n<\/ul>\n\n\n\n
- Excessive CSS or inline styles<\/strong> may resemble spammy design patterns.<\/li>\n\n\n\n
- Too many nested tables<\/strong> \u2013 While tables are common in email design, excessive nesting makes code heavy and harder for clients to render.<\/li>\n\n\n\n
- Unclosed tags<\/strong> \u2013 Leaving <table>, <tr>, or <td> tags unclosed can break rendering.<\/li>\n\n\n\n