A Guide To Email Preheaders - Benefits and Best Practices

The adage goes — you never get a second chance to make a first impression. And it also applies perfectly in the marketing realm, whereby if you fluff your lines at the first instance, you may never get the chance to undo the damage. 

In email marketing, you either hook or lose your recipients within the first few seconds they see your email.

The big question is: How do you break through your subscribers' noisy email inboxes or junk folders? How do you entice them to open your emails? What's the proverbial carrot?

Besides building a reputable brand name, you require strong subject lines and email preheaders

Email preheaders and subject lines are like Robin and Batman. Initially, most marketers used preview texts (Robin) as aides to subject lines (Batman). However, the two developed strong interdependence over time, making them inseparable.

So, what is an email preheader? What's the difference between a subject line and a preheader in email marketing? And most importantly, how can you use the two to enhance your email open rates?

Unlock the power of email preheaders for effective cold emails with valuable insights, benefits, and expert best practices.

What Is An Email Preheader?

An email preheader or preview text is a small text line appearing below the subject line in an email inbox. Usually, it’s one sentence long and summarizes the email's contents.

A well-written email preheader can get subscribers' attention and persuade them to open your email. They can — and should — work together with subject lines to give recipients a glimpse of what they'll miss by not reading your emails. 

A few years ago, most organizations primarily focused on subject lines. Using a preheader in email marketing was a secondary strategy businesses used to gain a competitive advantage. Fast forward to today, preheader text emails are a must-have. 

In fact, if you fail to add a preheader text, most Internet Service Providers (ISPs) will include site navigations, your brand name, or disclaimers in the space where the preview text should be.

An Email Preheader vs. A Johnson Box 

We cannot conclusively answer the question 'What is an email preheader' without discussing a Johnson Box. In fact, several marketers believe preheaders are modern-day versions of the old-school Johnson Box.

In the early 1940s, Frank H. Johnson invented the concept of summarizing a letter's contents in a small box above the salutations. This box became popularly known as a Johnson Box.

A preheader in email correspondence works the same way as a Johnson Box. Both options aim at persuading recipients to read your messages.

How Do Preheaders Show In Recipients' Email Inboxes?

The way preheaders appear in subscribers' inboxes varies from one email service provider to another. For example, in Gmail, they follow the subject line immediately, while in Yahoo, they come under the subject line. 

However, the general rule is the brand name appears first, then the subject line, and, finally, the preview text.

How To Preview Texts To Email Campaigns

The process of setting up preheader text emails also varies from one ISP to another. However, the two most common methods are by using an HTML div attribute or through CRM software. 

As outlined above, email service providers often auto-generate preheaders for senders who don't add them. While the auto-generated email preheader might be enough, it may not be as captivating as a customized one.

What Are The Benefits Of Adding Preheader Text?

Below are a few reasons you should add a preheader to your email:

Gives A Preview Of What Is Contained Within Email Emails

A preheader text typically summarizes an email's content. It can give recipients an idea of what's in your email, enabling them to decide whether the message is essential or relevant. 

If subscribers find your subject line and preheader enticing, they will likely open your emails. And the opposite is true.

Increases Email Open Rates

According to EarthWeb statistics, the average email user receives 100 to 120 daily business emails. Simply put, the prospects in your email lists get marketing messages from over 100 companies like yours daily.

The competition is ridiculous and is getting crazier by the day. To stay above it, ensure any email you send out has a well-written subject line and preheader.

Well-written preheader texts can help you pique your recipients' interests, convincing them to read your emails. Studies show this strategy can effectively increase email open rates by up to 30%

It Helps You Avoid Auto-Generated Random Preheaders

As previously outlined, email service providers show random texts like "You are part of Company X's email list; you can unsubscribe here' or 'View in a web browser' on emails without custom preheaders. 

Alternatively, the recipient's email client can pick bits of text at the beginning of your email and show it as the preview text. 

While such auto-generated preheaders can give recipients a sneak peek of your emails' contents, they often look generic. Therefore, they can make your email look robotic, tainting your reputation with subscribers and lowering your chances of getting email opens.

What Is The Optimal Email Preview Text Length?

The correct response to this question varies from one email client to another. However, based on our research, an ideal preheader text should contain between 35 to 40 characters for phone email clients and 35 to 140 characters for desktop email clients. 

Any extra words that surpass these thresholds won't appear in recipients' inboxes.

Should you use the desktop or mobile threshold? To be safe, stick to 35 to 40 characters unless you're surefire certain all your recipients use desktops. In most cases, mobile users account for a larger chunk of opens. 

According to Campaign Monitor, 47% of regular email users check emails using mobile devices, with desktops accounting for only 26.9%. Above all, ensure the first part of your preheader text contains the most crucial information. 

Below are three other things to keep in mind as you craft your preheader:

  • If the text is too short, the recipient's email client might complement it with additional information from the beginning of your email
  • Mobile email clients show fewer characters than desktop email clients
  • Many desktop clients rely on the subject line's length to determine how much of the preheader they'll display 
  • If you have to use a long preheader, hook the recipients with the most enticing information in the first sentence 

Subject Line and Preheaders Best Practices

Before writing an email preheader, scrutinize your email to identify the most crucial information. Next, sum up the identified information in 35 - 40 characters. Here are six best practices to help you achieve this:

  1. Stay On Topic

Do not use the preheader to introduce new information you haven't discussed in the email or subject line. Recipients usually expect the preheader text to summarize the email. Therefore, they'll be disappointed if they can't match your preview text to your email content. 

It's like having a banner with the inscription 'Delicious Chicken Wings' at the entrance of a hardware store.

Instead of using the preheader to introduce new information, connect it to your subject line and email. For example, you can ask a question in the subject line and provide an answer in the preheader. 

Similarly, you can introduce the email's content in the subject line and use the preview text to ask the recipients to open the email for more details.

  1. Encourage The User To Learn More

Preheaders offer a perfect opportunity to ask recipients to open your email directly. Use it to explain to recipients how they'll benefit from reading your emails or outline what they'll miss if they don't. 

Think of it like a cold email within an email. 

Always assume the recipient doesn't know your brand or has no interest in what you're talking about. This approach will enable you to go beyond the generic "Learn more" or "Read more" CTAs by explaining to subscribers why they should take specific actions.

  1. Include Personalization

There's no doubt personalization is the most crucial factor in email marketing. With several businesses targeting prospects with the same products as yours, the best way to stay ahead of the park is to address recipients using their pain points.

When creating email marketing strategies, several organizations focus on making conventions and driving revenue — and that's where they get it wrong. Your primary focus should be your prospect's interests. 

If you can meet them at their points of need and position your products as a potential solution, you won't have to worry about sales. Before writing your preheader (and email), ask yourself what the subscribers want. 

Next, customize your email, subject line, and preheader to target these needs. Below are a few tips you can use:

  • Address the  recipients using their names
  • Keep your message concise and direct to the point
  • Acknowledge your understanding of the reader's pinpoints
  • Focus on how you can help recipients resolve their issues
  • Position yourself as a reputable brand within your industry
  1. Avoid Negative Keywords (Spam Trigger Words)

Research shows businesses and individuals send over 347.3 billion emails daily, out of which over 56.5% are spam. Because of this, most email service providers have strict spam filters to safeguard clients from unsolicited emails. 

These filters typically scan emails for specific spam-trigger words. Examples of these negative keywords include:

  • Dear Friend
  • Double your cash/income
  • Pure profit
  • Save big money
  • Don't miss out
  • Million dollars
  • Satisfaction-guaranteed
  • Fast cash
  • 100% free
  • Cents on the dollar
  • Free Money

The list is endless. If your preheader has several spam trigger words, your email will likely land in recipients' spam folders, lowering your open rates.

How do you identify the negative keywords to avoid? The trick is personalization. Avoid generic terms that promise heaven on earth.

  1. Avoid Emojis

Undoubtedly, colorful emojis can help your emails stand out in your recipients' inboxes. While using these graphics in the email content is okay, they usually don't properly load when included in email preheaders. Therefore, it's best to avoid them.

  1. A/B Test Your Subject Lines And Email Preheaders

A/B testing your preheaders can help you identify what does or doesn't work. Add different preheader texts and subject line combinations to your A/B rotation and note the strategies that earn the most clicks. 

Doing so can help you understand your email list better, identify dormant subscribers, and increase your open rates.

Above all, personalization is key. There's no one-shoe-fits-all preheader strategy that works for all industries. Be open to learning new ideas and implementing new strategies. We are always available for consultation if you need expert help.


There’s no better way to start strong on your cold emails than with a perfectly done preheader to complement your subject line. We have now equipped you will all the email preheader insights and the way to stand out from the rest of the pack. Take heed of our counsel and give your email marketing campaign a chance to fly higher than you even projected. For further insights, check out our blog for more on streamlining your emails. We always got you covered. 

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