Plain Text Email vs HTML Emails: Pros, Cons and When to Use Each

A plain text email contains only unformatted characters: no images, colors, fonts or buttons. An HTML email is built with HyperText Markup Language, the same code as a web page, so it can carry a logo, a layout, images and clickable buttons. Most marketing emails are HTML, most personal emails are plain text, and the best practice for any email marketing campaign is to send both at once as a multipart message. This guide explains how each format works, what it does to deliverability, accessibility and tracking, and how to choose.

Key takeaways

• Plain text email = text only (Content-Type: text/plain). HTML email = coded design (Content-Type: text/html).
• HTML emails win on branding, layout, buttons and open tracking. Plain text wins on personal tone, universal rendering and simplicity.
• Neither format is "spam-proof". Authentication (SPF, DKIM, DMARC), sender reputation and engagement matter more than the format itself.
• Send HTML campaigns as multipart/alternative: one HTML part plus one plain text part. HTML-only mail is a mild spam signal.
• Mailpro generates the plain text version of every HTML campaign automatically, and you can edit it.

What is a plain text email?

A plain text email is a message made only of basic characters, sent with the MIME type text/plain. You cannot bold a word, insert a logo, change a font or add a button. Links appear as full URLs, and every recipient sees exactly the same thing, whatever app or device they use.

That simplicity is the point. A plain text email reads like a note from a colleague rather than a brochure, which is why sales follow-ups, founder letters and many transactional messages still use it. Plain text messages are small, load instantly on slow connections, display on smartwatches and text-only clients, and never "break" in rendering.

Pros and cons of plain text emails

• Pros: personal tone, identical rendering everywhere, tiny file size, nothing to code or test, works in every client.
• Cons: no branding or images, long raw URLs instead of buttons, no open tracking (there is no place for a tracking pixel), harder to scan when the message is long.

What is an HTML email?

An HTML email is a message whose body is written in HTML and CSS, sent with the MIME type text/html. When the recipient opens it, the email client renders the code much like a browser renders a web page, so the message can include images, colors, columns, tables, styled headings and buttons for a clear call to action.

HTML email is the standard for newsletters, promotions, product announcements and most automated emails. Almost every modern email client supports it, and it is the default compose mode in Gmail, Outlook and Apple Mail. Email HTML is not the same as web HTML, though: many clients strip <head> styles and external stylesheets, so email designers use table-based layouts and inline CSS. Our guide to HTML and CSS for email design covers the coding side in detail.

Pros and cons of HTML emails

• Pros: brand identity (logo, colors, fonts), visual hierarchy, clickable buttons and linked text, images and product grids, open and click tracking, responsive layouts for mobile.
• Cons: rendering differs between clients (Outlook desktop is the usual troublemaker), dark mode can invert colors, heavier messages, more to test, and poorly coded or image-only HTML attracts spam filters.

Plain text vs HTML emails: side-by-side comparison

Do plain text emails get better deliverability than HTML emails?

Not automatically. Deliverability, the share of your emails that reach the inbox, is not decided by format alone. Plain text emails have fewer things that can go wrong, but mailbox providers such as Gmail, Yahoo and Outlook decide inbox placement mainly on sender reputation, authentication and how recipients engage with your mail, not on the format. A well-built HTML newsletter from an authenticated, reputable sender reaches the inbox; a plain text blast to a bought list does not.

Where format does matter is in the details spam filters score:

• HTML-only messages. SpamAssassin, the open-source filter many providers build on, has a rule (MIME_HTML_ONLY) that adds points to messages with no plain text part. A multipart message avoids it.
• Image-only emails. A single large image with little or no text looks like an attempt to hide content from filters. Keep real, readable text in the HTML.
• Messy code. Markup pasted from Word or broken tags add weight and can trigger filters. Pasting as plain text before styling avoids most of it.
• Mismatched parts. A plain text part that says something different from the HTML part is a classic spam pattern. Both versions should carry the same message.
• Size. Gmail clips messages larger than about 102 KB and hides the rest behind a "View entire message" link, which can also hide your unsubscribe link.

Above all of this sits authentication. Since February 2024, Gmail and Yahoo require bulk senders to pass SPF and DKIM and publish a DMARC record, whatever the format. See our Gmail and Yahoo sender requirements checklist for the full list.

Which format is more accessible?

A well-coded HTML email is usually the most accessible option, and a badly coded one is the least. Screen readers read plain text in order, which is reliable, but they also read every raw URL character by character and cannot convey headings or emphasis. HTML can give screen-reader users real structure, as long as the code is written for it:

• Add descriptive alt text to every meaningful image, and empty alt text (alt="") to decorative ones.
• Use real headings and live text, never text baked into images.
• Mark layout tables with role="presentation" so screen readers do not announce rows and columns.
• Set the language (lang="en") and keep sufficient color contrast, including in dark mode.
• Write link text that makes sense out of context ("Download the invoice", not "Click here").

The plain text part of a multipart email is the safety net: some assistive tools, smartwatches and text-only clients use it directly.

You do not have to write two versions by hand: Mailpro builds the plain text part of every HTML campaign for you, and pricing is based on emails sent, not contacts. See Mailpro pricing.

What is a multipart/alternative email?

A multipart/alternative email is a single message that contains two versions of the same content, a plain text part and an HTML part, so each email client can display the best version it supports. It is defined in the MIME standard (RFC 2046) and it is how virtually every professional email platform sends HTML campaigns.

The order of the parts matters: the simplest version comes first and the richest last, and the client shows the last part it can render. A simplified multipart message looks like this:

Content-Type: multipart/alternative; boundary="b1"

--b1
Content-Type: text/plain; charset="UTF-8"

Hi Anna, our spring collection is here: https://example.com/spring

--b1
Content-Type: text/html; charset="UTF-8"

<html><body><h1>Hi Anna</h1><a href="https://example.com/spring">See the spring collection</a></body></html>

--b1--

Gmail or Apple Mail shows the HTML part. A text-only client, a smartwatch or a reader who has switched off HTML sees the plain text part. Nobody gets a blank or broken email, which is why multipart is the default recommendation. The glossary entry on plain-text and multipart email gives the short definition.

How to write a good plain text version

• Keep lines short (under about 70-78 characters) and split sections with a blank line or ---.
• Write full URLs, not shortened links, so readers can see where they go.
• Keep the same message and offer as the HTML version.
• Make the unsubscribe URL visible, not buried.

In Mailpro, the text version is extracted automatically from your HTML and can be edited in its own tab before sending; the FAQ on plain text versions shows how.

Tracking: what you can and cannot measure in each format

Open tracking only works in HTML emails, because it relies on a tiny invisible image (a tracking pixel) that loads when the message is displayed. A plain text email has nowhere to put that image, so its opens cannot be counted. Clicks can still be measured in plain text if the platform rewrites links through a redirect, but the reader then sees a long tracking URL.

HTML emails let you measure open rates, clicks per link, devices and timing. Keep in mind that open rates are inflated since Apple Mail Privacy Protection started pre-loading images in 2021; clicks and conversions are the more reliable signals.

When should you use plain text emails?

Use plain text when the message should feel personal and the content matters more than the presentation:

• One-to-one sales outreach and follow-ups, especially in B2B
• Founder or account-manager letters that should read like a real person wrote them
• Simple system notifications such as password resets or login alerts
• Re-engagement emails where a quiet "Are you still interested?" outperforms a designed promo
• Audiences that read on text-only clients or prefer minimal email

Many senders use a hybrid: a "simple HTML" email that looks like plain text (no images, one column, a signature) but keeps clickable linked text and open tracking.

When should you use HTML emails?

Use HTML when design helps the reader act or understand:

• Newsletters with several articles or sections
• E-commerce promotions, product grids and abandoned-cart reminders
• Event invitations, webinars and confirmations with dates, maps and buttons
• Brand announcements where the logo and colors build recognition
• Any campaign where you need open and click data to segment and test

Before sending an HTML campaign, preview it on desktop, mobile and in dark mode, and run through an HTML email QA checklist.

How Mailpro handles both formats

Mailpro lets you send plain text, HTML or both from the same account:

• Build HTML emails in the drag-and-drop HTML editor (see how to create a newsletter easily), start from 600+ templates, or import your own HTML.
• Every HTML campaign is sent as multipart, with a plain text version generated automatically and editable before sending.
• Authenticate your domain with SPF, DKIM and DMARC, and let automatic bounce handling keep your list clean.
• Track opens and clicks in the campaign statistics.
• Send transactional messages in either format through the Mailpro SMTP server or API.

Frequently asked questions

Are HTML emails bad for deliverability?

No. HTML emails reach the inbox when the sender is authenticated, the code is clean, there is real text alongside images and a plain text part is included. Deliverability problems usually come from reputation, list quality or missing authentication, not from HTML itself.

Can I track opens in a plain text email?

No. Open tracking needs an image pixel, which a plain text email cannot contain. You can still track clicks if links are rewritten, and you can track opens on the HTML part of a multipart email.

Should every HTML email have a plain text version?

Yes. A plain text alternative helps accessibility, gives text-only clients something to show and avoids the spam-filter penalty some filters apply to HTML-only messages.

How do I send a plain text email from Gmail or Outlook?

In Gmail, open the three-dot menu in the compose window and choose "Plain text mode". In Outlook, go to Format Text and select "Plain Text". For campaigns to a list, use an email marketing platform rather than a personal inbox.

What is the maximum size for an HTML email?

There is no universal limit, but Gmail clips messages over about 102 KB of HTML. Keep your code lean and host images rather than embedding them.

Do people prefer HTML or plain text emails?

It depends on the message. Readers expect HTML for newsletters and promotions, and plain text often performs well for personal, one-to-one style messages. A/B test both on your own audience before deciding.