Plain text or HTML, and why cold email leans plain

The moment a cold email looks like a marketing email, it is treated like one, by the filter and by the reader. Plain text is not a limitation here, it is the disguise that makes cold outreach look like what it should be: a person writing to a person.

Cold email is not marketing email

Designed HTML emails, with images, banners and buttons, are built for opted-in marketing audiences. Cold outreach is trying to look like an individual reaching out, and design breaks that illusion instantly.

A plain-looking email matches the pretext of a personal message, which is exactly what makes it credible to a stranger.

HTML weight hurts deliverability

Images, tracking pixels and multiple links are among the signals spam filters weigh, and heavy HTML looks like bulk marketing. Plain or near-plain email is lighter and reads as personal, which helps it reach the inbox. This is the same logic behind a minimal signature and dropping tracking pixels.

Design lowers trust from a stranger

A polished template from an unknown sender reads as a campaign, and campaigns from strangers get deleted. A plain note reads as a real person who might actually want a reply.

The absence of design is doing work: it signals that this was written, not blasted.

Light formatting is fine

Plain does not mean ugly or unstructured. A little formatting, short paragraphs, the occasional line break, is fine and aids readability. What to avoid is the newsletter look: images, big buttons, columns, brand headers. Keep it to what a person would naturally type in a normal email.

The rule of thumb

If it looks like something a colleague could have typed to you, it is right. If it looks like it came from a marketing platform, it is wrong. Cold email leans plain because plain is what reads as personal, and personal is what gets answered.