Should you include images or attachments in cold emails?

You've spent time crafting the perfect cold email. The copy is tight, the offer is clear. Then someone suggests adding a logo, a PDF, or a product screenshot. Should you?

The short answer is no. Plain text wins in cold outreach, and it's not even close.

Why images hurt cold emails

Most email clients block images by default until the recipient actively allows them. So that carefully chosen screenshot? It shows up as a grey box with a broken placeholder. That looks worse than no image at all. Beyond that, HTML-heavy emails with embedded images read as marketing or promotional content to spam filters, and that's exactly where they'll route your message.

Tracking pixels count here too. A tracking pixel is just a tiny invisible image used to detect opens. Privacy-focused clients (and Apple Mail's Mail Privacy Protection) actively block these, which means your open rate data becomes unreliable anyway.

Why attachments are even riskier

Security gateways at corporate email systems scan every attachment from an unknown sender. Many quarantine or delete them outright before your recipient ever sees the email. And even if the attachment gets through, most people won't open a file from someone they've never heard of. That's just good security hygiene on their end.

Attachments also send a signal: "I want something from you right now." That's the opposite of how a good first-contact email should feel.

What to do instead

Still if you have something worth sharing, a case study, a proposal, a deck, mention it by name in the email and offer to send it once they reply. That single step filters for genuine interest and keeps your first message clean. If you need to reference a resource, link to a hosted page they can choose to visit. A URL to your website or a Google Drive folder is completely fine. What you want to avoid is embedding an auto-download link directly in the email body, since security gateways flag those.

Plain text cold emails look like they came from a real person. That's exactly the impression you want. No one forwards a newsletter-style HTML email to a colleague and says "worth a read." But people do forward simple, well-written notes.

But one practical exception worth knowing about: a small logo in your email signature is generally fine, as long as it has alt text and isn't the centrepiece of the message. Some cold outreach tools also support personalized images (like a custom screenshot with the prospect's name or website on it). Those can work, but only if your tool handles them cleanly and the image genuinely adds something specific to that person.

If you're not sure how your cold email setup looks to filters before you hit send, our Email Header Analyzer can help you spot what's actually reaching the inbox. Or if you want a quick gut-check on your whole sequence, drop us a message and we'll take a look.