Does including alt-text on images in your email signature really help your spam score?

Other Factors That Impact Spam Score More

While adding alt-text is a good practice, it’s just one piece of the puzzle when it comes to email deliverability. Spam filters use complex algorithms to determine whether an email should land in the inbox or the spam folder. Other factors, many of which have a much bigger impact than alt-text, can significantly affect your spam score. Here are some of the most important ones to keep in mind:

Too Many Images

Emails that are mostly images and have little text are often marked as spam.

Large Image Sizes‍

Overly large image files in signatures can increase spam score.

‍Broken Links or Tracking Pixels

If your signature has image URLs from questionable sources or excessive tracking pixels, it can hurt deliverability.

‍Spammy Words‍

Words like "free," "guarantee," or excessive use of exclamation marks can trigger spam filters.

Best Practices for Email Signatures

• Use a Balanced Text-to-Image Ratio - A simple, professional signature with a mix of text and a small logo works best.
• Include Alt-Text - Describe the image in a natural way (e.g., "Company Logo – XYZ Landscaping").
• Host Images on a Reputable Server - Instead of embedding images as attachments, host them on a reliable server and link to them.
• Avoid Too Many Links - Limit to essential links (website, social media) to avoid looking like a phishing attempt.

Alt-text alone won’t dramatically improve your spam score, but it’s part of a set of best practices that contribute to better email deliverability. The biggest improvements come from maintaining a good text-to-image ratio, avoiding spammy content, and using reputable email servers.