Stop using images and HTML in your cold emails. Here is why

plaintext_pete · 2026-03-14 · 1,890 views

I know this is going to be controversial but after testing plain text vs HTML across 50,000+ cold emails over 6 months, the data is clear. Plain text wins and it is not even close.

The test: Same prospect lists, same inboxes, same sending schedule. Only variable was email format. Group A got HTML emails with styled formatting, a company logo, and a button CTA. Group B got plain text emails with no formatting, no images, no links in the first email.

Results:

• HTML emails: 2.1% reply rate, 67% inbox placement
• Plain text emails: 3.4% reply rate, 84% inbox placement

Plain text got 62% more replies and 25% better inbox placement. Here is why.

Spam filters flag HTML-heavy emails. Cold emails are supposed to look like one person writing to another person. When was the last time you sent a colleague an email with styled HTML, embedded images, and a designed button? Spam filters know this too. Heavy HTML formatting is a signal that an email is marketing material, not a personal message.

Images trigger tracking pixel detection. Even if you are not using open tracking, embedded images can trigger the same spam filter rules. Some corporate email filters block external image loading entirely, which means your carefully designed email shows up as a wall of broken image icons.

Plain text looks like a real email. When a VP of Sales opens their inbox and sees a short, plain text email that reads like it was written by a person, they are more likely to engage. It does not look like a newsletter. It does not look like marketing. It looks like someone took 30 seconds to write them a note.

What about links? Skip links entirely in your first email. Links are another spam trigger, especially shortened URLs or tracking links. If a prospect is interested, they will reply, and you can include relevant links in the follow-up. Save your case study link, your calendly link, and your website for emails 2-4 in your sequence.

The exception: if you are targeting creative roles (designers, marketers) where visual presentation matters, a well-designed HTML email can work. But for 90% of B2B cold email targeting executives and decision makers, plain text outperforms HTML every single time.