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A/B Testing: 5 Email Elements to Test to Ensure Success

Kayla Mejer |5 min Read

A/B Testing: 5 Email Elements to Test to Ensure Success

For years, A/B testing has been a top marketing initiative for organizations spanning all industries. Even Dell earned a 300% increase in conversion rate thanks to A/B testing. And we don’t expect the momentum to slow down anytime soon. According to QY Research, the global A/B testing software market is projected to be worth $1.08 billion by 2025.

A/B testing is the ultimate experiment to understand what really matters to your target audiences. The process requires you to split up your audience and test a number of variables in a marketing campaign to determine which performs best. This article aims to place a spotlight on the various ways you can A/B test an email to maximize the impact of your email marketing strategy overall. Let’s dive in!

How to A/B Test Like a Pro

First, you need to determine what you’re A/B testing for. Will you be testing the efficacy of a subject line? Or maybe you want to experiment with the tone or main call to action. Either way, this is the primary step in conducting an A/B test. Next, you’ll need to separate your audience into multiple segments (one for each variation you plan to test for). Make sure that each list includes roughly the same amount of people so that the data is as comparable as possible. Then send out the first version of the email to one segmented list and the next version of the email to the second list, and so on.

Once a few days have passed since the initial emails were sent, take a look at the data in regards to the click through rate — this tells you how many contacts engaged with your email by clicking on the links within it. Which email garnered the most engagement? Based on this data, you’ll be better able to recognize which variation of layout or copy resonates best with your audience. Moving forward, you can optimize your emails to garner the most engagement and conversions.

1. A/B Testing the Layout of the Email Can Offer Better Results

A/B testing goes beyond just the marketing copy. Even email layouts can be improved through A/B tests. Take a look at the mock-up below. The email on the left has a simplified design whereas the email on the right is a little more bold and complex. The question is, how will you know which email layout yields better results?The email on the left has a simplified design whereas the email on the right is a little more bold and complex. Typically, emails with a clear and concise design perform better than those with a complex layout. If this theory held true for this mock-up example above, that would suggest that the email on the left received a higher click through rate than the one on the right. In response to this “data” and to ensure that your emails moving forward are optimized for maximum engagement, it would be best to leverage email layouts with a simplistic and streamlined design moving forward.

2. Testing the Subject Line is Key to Increasing Open-Rates

As discussed above, the subject line is one of the most important email elements to A/B test. Subject lines are a reader’s first impression of your email. The subject line needs to capture the reader’s attention right away and intrigue them enough to actually open the email. 

Below is an example of one subject line written in multiple ways:

Fear of missing out:

“Last chance to sign up for the webinar - Adopting a DevOps Mindset”

Curiosity peaking:

“5 reasons to adopt a DevOps mindset. Sign up for the webinar to learn more”


“You’ve got it all! Except for a DevOps mindset. We can help - Join our webinar”

Pain point addressing:

“Accelerate deployments with a DevOps mindset - sign up for the webinar”

Social proof:

“97% of organizations that have adopted a DevOps Mindset reach market faster”

A/B testing subject lines is key to understanding your audience’s preferences. Once you are able to see which different types of phrasing and word choice garner the most attention, you’ll be better able to improve your email marketing strategy over time. As buyers’ wants and needs change over the years, A/B testing enables you to keep up to date with your customers’ growing expectations.

3. Ensuring the Call to Action Grabs Your Audience’s Attention is Vital

The most important part of an email is the call to action (CTA). But the way in which a CTA is presented can make or break the effectiveness of your email. There are so many ways a CTA could be presented poorly:

  • Too soon in the email — If there isn’t enough supporting information given prior to the CTA, how will people know why they should click on it? 
  • Too late in the email — If the email is too long, people might not reach the end to actually see the CTA.
  • Hidden within the body copy — If the CTA is in a convoluted location that’s difficult to find, odds are, no one is going to find it!

However, there are a few best practices for ensuring the CTA in your email is in a prime location:

  • Make it stand out — Include enough white space around the CTA button to ensure the button is easy to see.
  • Make it bold — Use contrasting colors to the rest of the email to make your CTA button visually pop.
  • Use clear and concise messaging — Keep the copy for the CTA short and to the point.

So, how do you know which type of CTA will resonate best with your audience? A/B test it! For example, say you were to test out the copy of the CTA and see whether or not a clever or simple CTA garners higher conversions. Look at the example of two CTA options below.A/B testing - example of two CTA options. On the left, we have a simply-worded CTA and on the right, we have a more descriptive CTA. By sending out both emails to separate lists of the same buyer persona, you’d be able to see which CTA performed better by taking a look at the number of conversions this email generated. From here, you can better tailor your future CTAs to either be more simplistic or more detailed to generate more conversions.

4. A/B Testing the Time of Day Can Dramatically Improve Email Success

A/B testing is also beneficial when it comes to determining which time of day and which days your audience is most likely to engage with your emails. Even small changes in the date and time of an email send can alter the success of the email. According to Experion, Tuesday emails have the highest open rate (18%) compared to any other day, with Thursday being the second best. To prove the point further, EngineMailer reports that “emails sent on Tuesday have the maximum number of open rates, resulting in a better CTR and higher site traffic.”

But is this true for your audience? It’s important to remember that your audience is different than other company’s — even your competitors. What is typically “the norm” for others, may not be the case for your organization. It’s best to A/B test sending out your emails at various dates and times while still remaining cognizant of your audience’s:

  • Occupation
  • Main pain points
  • Typical daily life

Having a good sense of the above bullet points will help you better understand your ideal buyer’s work schedule so that you can hit their inbox when they’ll actually see it. This brings us to the next factor to A/B test — time of day. 

According to Omnisend’s research, email open rates peak at 8 AM, with an average open-rate of 20.32%. Conversely, Omnisend found that the best time to send promotional emails is at 5 PM due to this being the top-performing time for increased click through rates. When determining which times of day would be most lucrative to A/B test, ask these questions:

  • When would my target audience most likely take a break?
  • When would they go to lunch?
  • What is their typical work schedule like?

From here, you’ll be better prepared to effectively test which time of day will prove to be most effective at:

  • Reaching a high open-rate
  • Receiving an increase in click through rates
  • Garnering the most conversions 

5. Changing Up the Copy’s Tone & Point of View Can Alter Email Effectiveness

The last, but not least, email elements that should be A/B tested are the copy’s tone and point of view. Changing the point of view to second person versus third can drastically alter the effectiveness of the email. Emails written in the second person point of view typically perform better than those written in third person. When writing in second person, marketers use words like “you” and “your.” This makes the email feel much more personal and holistic. And as you know by now, personalization is key to effective inbound marketing.

On the other hand, writing emails in the third person using words like “a marketer” or “sales reps” don’t address the reader in a personalized manner. Thus, these emails may come across as cold and impersonal, leading to less impactful results.

Sometimes a change in tone is all it takes to pique readers’ interest and generate increased conversions. For example, say you need to write an email about how developers are using Kubernetes in interesting ways. Ask yourself, how would I want to learn about this? 

Would you want to read something this cool in a serious manner such as, “Developers are using Kubernetes to create apps that connect people in real life through online gaming…”? Eh, boring! 

Wouldn’t you find it more intriguing if the copy said, “Developers are using Kubernetes to create virtual reality applications that bring people together on the hunt for magical (virtual) creatures.”? Now, that sounds like a good time! Simply changing the tone from serious to fun or even funny, for example, can boost email effectiveness and dramatically increase engagement and conversions.