Plain Text vs HTML Email: What Reaches the Inbox in 2014?

AWeber’s Director of Deliverability clarifies the issue of which type of email (HTML or Plain Text) gets the best email deliverability.

HTML vs PlainText
We’ve heard it all over the place: “I send plain text emails because HTML emails get filtered into the spam folder.”

But is the belief that plain text emails get better email deliverability than HTML ones rooted in reality?

We sat down with our Director of Deliverability, Mohammed Ahmed, to find out.

The answer, it turns out, isn’t so black-and-white.

HTML Isn’t Automatically Less Deliverable, But…

According to Mohammed,

“If you send an email with broken HTML, it could possibly be the tipping point for an email already in danger of landing in the spam folder. Or if it’s broken enough that your users can’t read it, they may mark it as spam.”

So certain HTML emails — poorly coded ones — can potentially experience poor delivery rates.

But of course, not all HTML emails are poorly coded.

So why the urban legend about HTML being less deliverable than plain text?

A Little History Of HTML And Spam

Over time, ISPs like Yahoo, AOL, and Comcast have used various filters to protect inboxes from unsolicited messages.

Spammers, eager to keep reaching potential customers, looked for and often found ways to get their emails past the filters. Naturally, ISPs adjusted their filters in response. And the pattern continued to repeat.

Since HTML emails have more components than plain text (code, images, etc), filters have historically given them a harder look.

So will those filters, designed to catch spam, inadvertently keep your HTML emails away from the people who signed up to get them?

In short, not really.

In 2012, we talked to Laura Atkins of Word To The Wise, who shared that while HTML-only emails were more likely to be filtered, when the they were were accompanied by a plain text version, this wasn’t the case:

“If you send mail that is heavy on the images and low on the text, it’s going to look like spam. This doesn’t mean it’s going to be a delivery problem necessarily. But, if the mail has other issues: mentions domains that have iffy reputations or recipients that aren’t engaged then a heavy image to text ratio may be enough to tip the mail into the bulk folder.”

Here’s How Things Stand In 2014

HTML email can only affect your deliverability if you have a broken tag, or if you’re not sending that plain text version.

No plain text version? To a filter, that may look like you’re trying to slip something shady through.

Note: when you create HTML emails in AWeber, we’ll automatically generate a plain text version to create a good experience for your subscribers AND to support high email deliverability. So we’ve got you covered there.

And if your HTML email contains a broken tag? In that case, it’s not the filters you need to worry about.

In Mohammed’s words, “If you have a broken tag, it means [readers] are probably going to click on the report spam tag, because they’re not seeing the mail they’re supposed to see.”

These spam reports damage the reputation of both your site’s domain name and the IPs your emails are being sent from. If either develops a reputation for sending high levels of spam (or emails reported as such), your future messages are more likely to be flagged.

Now, here’s the really good news:

When you create your email marketing campaigns in AWeber using our drag-and-drop message editor, we’ll automatically make sure your HTML is correct and valid. We’ve got you covered there, too.

The Best of Both Worlds

The bottom line: if you’ve been holding back from sending HTML emails because you’re afraid of poor email deliverability, it’s time to stop.

You can send beautiful HTML emails AND get good delivery, too.

Other Questions About Getting Great Delivery Rates?

It seems like every time I meet customers, deliverability works its way into the conversation.

What else would you like to know about email marketing and reaching the inbox?

Add your thoughts and questions below; we’ll address them here and/or in a future blog post.


  1. Rishi

    4/22/2014 12:33 pm

    Awesome article Justin! I had this question the other day and now you have answered it. Thanks!

  2. Gilbert

    4/25/2014 7:50 pm

    This was a very good article Justin! Thank for the info. It’s good to be on board with AWeber. You guys are always on top giving us the best advice and top quality information.


  3. Matt Ferreira

    4/28/2014 1:14 am

    Broken HTML is the fastest way to get routed to the spam filter and one area that people don’t think this applies to, but in fact it does, is email signatures.

    Make SURE your email signature management vendor has this built into their product – stripping out of unnecessary divs/tables/span tags. It’s so important!

    We chose for this exact reason – our regular peer-to-peer emails (not even talking about our mass emails sent via Marketo) were being sent to spam at an alarming rate before we started using them.

  4. Amandeep Singh

    4/28/2014 3:52 pm

    Great article Justin… I have recently started sending out blog broadcasts and I always wondered what works well – HTML or Text…

    This article explains it much better now… thanks for sharing