Plain Text vs HTML Emails: How Small Businesses Should Choose

Use HTML for newsletters, promotions and anything that needs your brand to show up. Use plain text for personal, one-to-one messages. For most small businesses the best answer is both: an HTML email that carries a plain-text version with it. Below, I explain how the two formats differ, what they do to deliverability and results, and how to test them on your own list.

TL;DR

• Plain text is text only. HTML adds fonts, color, images, buttons, and layout, which is how your brand shows up in the inbox.
• Plain text does not reliably improve deliverability. Sender reputation and list quality matter more than format.
• Simpler emails often win on clicks in published tests, but those tests are not proof for your audience. Test your own list.
• Send HTML with a plain-text alternative, written with real text, alt text, and clear link wording.
• Use plain text for personal outreach and replies, and HTML for newsletters, offers, and welcome series.

Table of Contents

• What is the difference between plain text and HTML email?
• When plain text makes sense
• When HTML is the better choice
• Does plain text improve deliverability?
• What the click and open numbers actually tell you
• Accessibility and readability
• Why some emails show up as plain text
• The best of both: send HTML with a plain-text version
• A simple decision guide
• How to test which format works for your audience
• Our perspective
• Want email that looks like your business?
• FAQ
• Sources

What is the difference between plain text and HTML email?

A plain-text email is characters and nothing else. Microsoft’s Exchange documentation describes plain text as US-ASCII text with no fonts or other formatting, while HTML supports text formatting, background images, tables, bullet points, and other graphical elements.

That difference is more than cosmetic. It is also how the message is packaged. An HTML message has to be MIME-encoded to keep its formatting, while a plain-text message uses a text/plain content type, as Microsoft Learn explains. So to answer a common question: an HTML email is not a file you open in a browser. It is a message whose body is written in HTML and delivered through email standards.

Here is the practical comparison.

Apple’s guidance for Mail on Mac makes the same trade-off. Plain text omits formatting, tables, and images but is readable for all recipients, and rich text can include them but may be unreadable for some recipients.

When plain text makes sense

Plain text is the right tool when the message is a conversation, not a campaign. Think of:

• A reply to a customer question.
• A short note after a first meeting or quote request.
• A follow-up to a lead who has not responded.
• A personal check-in with a past client.
• Transactional messages where the one job is to deliver information.

In these cases a designed template can feel like a mass mailing. A clean text message reads like it came from a person, which it did. If you send outreach to other businesses, the same logic holds, and this piece on why wholesale outreach gets ignored shows how context and relevance shape whether a message gets read at all.

Plain text has one more advantage: it is the fallback. If an email app cannot display formatting, or a person prefers text, the plain-text version is what they see.

When HTML is the better choice

HTML earns its place when you want the email to look like your business. A logo, consistent colors, a clear button, and a layout that guides the eye all signal that you are established and organized. That matters for:

• Monthly newsletters with several items.
• Product or service announcements.
• Event invitations and seasonal promotions.
• Welcome series for new subscribers or customers.
• Anything where a clear call-to-action button helps the reader act.

HTML also gives you structure. The Section508.gov guidance on accessible email notes that plain-text messages do not allow images or design features, while HTML can provide structured elements. Its Outlook authoring guide adds that HTML or rich text can use headings and active hyperlinks to improve access for assistive technology. A long email with real headings is easier to navigate with a screen reader than a wall of unbroken text.

If you want layouts that work for newsletters in particular, we cover them in our guide to best email layouts for small business newsletters.

Does plain text improve deliverability?

This is the claim that sends many small business owners toward plain text, and it is shakier than it sounds.

Multiple email platforms say format is not the deciding factor. ActiveCampaign’s help center says plain text does not ensure better deliverability, and that most filters care more about sending history than whether a message is HTML or plain text. Dyspatch makes a similar case: plain text is not guaranteed to reach the inbox, and properly coded, tested HTML can deliver successfully.

What does matter, according to those same sources, is the stuff around the format:

• Whether people asked for your emails and expect them.
• How many people open, click, or reply.
• Bounce and spam complaint rates.
• The reputation of the domains you link to.
• Spam-trigger wording in the subject line and body.

There is one format-related risk worth fixing. HubSpot’s data article notes that properly coded HTML does not hurt deliverability when a plain-text version is included, while broken HTML and a missing text alternative can raise spam concerns. So the fix is not to abandon HTML. It is to code it cleanly and send the text version too.

You may also see claims that plain text gets better opens and clicks. Those are engagement results, not proof of inbox placement. Keep the two ideas separate.

What the click and open numbers actually tell you

Several published tests found simpler emails performing better. In HubSpot’s reported comparisons, a plain-text version generated 42% more clicks than a GIF version, and an HTML template with images had 51% fewer clicks than plain text. Those are real results from that company’s tested audiences.

Treat them as a reason to test, not a rule. Litmus ran its own comparison and found that engagement was slightly better for a plain-text-style version, but cautioned that the test changed the messaging as well as the format. When copy, audience, and design all differ, you cannot say which one caused the result.

There are a few reasons simple emails can win:

1. They look like they came from a person, so readers trust them more.
2. They load fast and never depend on images being turned on.
3. They put one message and one link in front of the reader, with nothing to compete for attention.

Notice that none of these is about plain text itself. A well-designed HTML email with one clear message, one button, and light styling can capture the same benefits. That is the approach we usually recommend.

Accessibility and readability

Plain text is readable by everyone, but that does not make it the most accessible option. Accessibility depends on structure and clarity, and HTML can provide both when it is built well.

For HTML emails, use these habits, which come from official and academic guidance:

• Keep real text as real text. Carnegie Mellon’s email guide advises never sending an all-image email, keeping actual text outside images, and using alt text, since some email clients do not load images.
• Use headings, lists, and left-aligned text. The UK Home Office design manual recommends accessible HTML practices for email such as headings, left-aligned text, lists, meaningful link text, and alternative text for images.
• Write links that say where they go. “View our spring menu” beats “click here.”
• Do not rely on color alone. Section508.gov recommends plain language, accessibility checking, and sufficient contrast, and says color should not be the only way to carry meaning.

Mobile is less of a concern than many people assume. The Open University’s guidance says both plain text and HTML reflow on mobile devices without special treatment, and that reflow helps screen-reader and mobile accessibility. Still, a single-column layout is the safest HTML choice on a phone.

The same thinking applies to your website. If this topic matters to you, our article on website accessibility for small business owners covers the basics.

Why some emails show up as plain text

If you have ever received a message that looks stripped down, there are a few ordinary reasons.

• The sender chose it. Outlook users can pick plain text, HTML, or rich text, and Outlook on the web offers plain text or HTML, according to Microsoft. Mac Mail users can switch using Format, then Make Plain Text or Make Rich Text, as Apple documents.
• The server settings changed it. Exchange admins can set the transmission format by domain or recipient.
• The receiving app could not read the formatting. Clients that cannot interpret Microsoft’s TNEF format may show only the plain-text version or an attachment, or ignore the formatted content.
• Your reply inherits the format. Replying to a plain-text message usually keeps it plain unless you change it.

If you want to switch your own settings, look for the compose or message format option in your email app. It is usually under the format or options menu while writing a new message.

The best of both: send HTML with a plain-text version

You do not have to pick one. The most reliable setup for marketing email is a message that carries both formats. The Home Office manual advises providing plain-text and HTML versions where possible. Technical guidance from Use Plain Text Email recommends that automated senders using HTML include a multipart/alternative message containing both versions, so the recipient’s email app can show whichever it can handle or the person prefers.

In practice, most email platforms do this for you. Look for a setting that generates or lets you edit the plain-text version, and read it before you send. An auto-generated text version can come out cluttered with long link URLs. Spend two minutes cleaning it up.

If you are comparing tools to send from, this look at email marketing platforms compared is a helpful place to see how features differ. For cost, our guide on email marketing cost for U.S. small businesses helps you avoid paying for more than you need.

A simple decision guide

Use this as a starting point.

Our welcome email series guide shows how a five-message sequence can be built in an hour, and that is a good place to apply the dual-format habit from day one.

How to test which format works for your audience

Published numbers come from other people’s lists. Yours may behave differently, so run your own test. The steps are simple.

1. Pick one list or segment. Choose an audience large enough to give you a meaningful result.
2. Change one thing. Klaviyo’s help center advises testing one variable at a time, and its examples include comparing template organization or images versus GIFs.
3. Keep the copy the same. If the words change as well as the format, you will not know what made the difference. Litmus’s own caution points the same way.
4. Choose a winning metric first. Clicks, replies, or conversions. Decide before you send, not after.
5. Decide how big and how long. The test size and duration depend on your audience and metric, so give it enough time for people to act.
6. Repeat. One test tells you about one email. Run a few before you change your standard.

A good test for a small business: send your usual newsletter as a light HTML email to half of a segment, and a stripped-down text-style version of the same copy to the other half. Compare clicks and replies. If the simple version wins, you can bring some of its qualities into your template: shorter copy, one button, less decoration.

Our perspective

Most small business owners come to us asking which format is “better.” The honest answer is that it is the wrong question. The right question is what the email needs to do for the person reading it.

A personal note should feel personal. A newsletter or welcome series should feel like your business. That means your colors, your logo, your voice, and a layout that is easy to read on a phone. When we build email design for a client, every template is bespoke. There are no stock layouts, and you work with me directly from start to finish.

We also build with restraint. One clear message, real text instead of text locked in images, meaningful links, and a plain-text version that is checked by hand. That gives you the trust of a simple message and the recognition of a branded one. You own every asset we create, with no licensing strings attached, so your email design can move with you if you change platforms.

Email works best when it matches the rest of your brand. If your website, your print pieces, and your inbox all look and sound like the same business, people recognize you faster and trust you sooner.

Charles

Want email that looks like your business?

If your emails feel generic or inconsistent with your website, we can help. We design brand and identity systems and plan marketing and strategy work for small businesses, including email layouts that carry your brand into the inbox.

If you are ready to talk about what your email should look like, get in touch through our site and we will take it from there.

FAQ

Is an email an HTML file?

Not in the way a web page is. An HTML email is a message whose body is written in HTML and packaged with MIME so formatting survives delivery. A plain-text email uses a text/plain content type instead. Either way, it is delivered through email standards, not saved as a file you open in a browser.

Are plain text emails less likely to go to spam?

Not reliably. Email platforms say sender reputation, engagement, complaints, and list quality matter more than format. Clean, tested HTML sent with a plain-text version can reach the inbox just fine. Broken code and a missing text version are the format problems worth avoiding.

Why are some emails in plain text?

The sender may have chosen plain text in their email app, a server setting may have converted the message, or the receiving app may not have been able to read the formatting. Replies also tend to keep the format of the message you are answering.

Should a small business send HTML or plain text newsletters?

Send HTML with a plain-text version for newsletters, promotions, and welcome series, since your brand and a clear button help. Keep plain text for personal follow-ups and replies. Then test both on one segment of your list to see what your own readers respond to.

How do I change from plain text to HTML in my email settings?

In most email apps, the option is in the format or options menu while you write a new message. On Mac Mail, it is Format, then Make Rich Text. In Outlook, you pick the message format while composing. Marketing platforms usually set the format per template.

Sources

• Message format and transmission in Exchange Online (Microsoft Learn)
• Content conversion: Exchange 2013 Help (Microsoft Learn)
• Use plain or rich text in emails in Mail on Mac (Apple Support)
• Accessible Email Messages (Section508.gov)
• Microsoft Outlook 365 Basic Authoring and Testing Guide (Section508.gov)
• Email Best Practices Guide (Carnegie Mellon University)
• Content formats for mobile devices (The Open University)
• Send users an email (Home Office Design System)
• Use plain text email
• Deliverability tips for content (ActiveCampaign Help Center)
• The Myth of Deliverability: Plain Text Email vs. HTML Email (Dyspatch)
• Plain Text vs. HTML Emails: Which Is Better? (HubSpot)
• The Results Are In: A/B Testing HTML vs. Plain Text Emails (Litmus)
• How to A/B test an email campaign (Klaviyo Help Center)