Email A/B Testing: 4 Ways to Improve Your Campaign Results


A/B testing your email campaigns, also known as split testing, means submitting two or more different versions of the same message to a sample of recipients, analysing the reaction to each version, and determining which one is most effective. The goal is to optimize individual aspects of the email to see which variation of the campaign achieves the best results, with the aim of improving performance.

Many businesses desire to increase their email engagement rates with their customers when they feel that their email marketing campaigns are not performing well. This is why A/B testing is so important to know what went wrong and how to improve email performance.

In this post, we analyse 4 elements which would allow an A/B test to improve email performance.


1. Subject Lines 

Changing one or two words is enough to give a decisive boost to the open rate. Creating A/B tests on the subject line is essential: for example, try comparing “Create your free profile today!” with “Do you want to create a free profile?” to see which one works best for you.

The length of subject line is an important consideration when sending out emails. According to Campaign Monitor, it shows that the optimal length is around 61-70 characters.



However, each subscriber is unique and they may react differently than those included in the study conducted above. Also, more people are reading emails on mobile devices or using different email clients which may affect the subject line length.

The only way to know the ideal length of your email subject lines for your audience is to test it and see what subject line length works best for your audience.


2. Email Copy 

According to this study, the average human attention span has fallen from 12 seconds in 2000 to 8 seconds today.

This reduction in attention span has significantly increased the importance of great writing. If you are unable to quickly and easily explain your product or offer, you’ll struggle to get your subscribers to click-through on your campaigns.

What does great copy look like for your audience?

Well, the length of copy varies depending on your business. The answer is largely going to depend on the design of your email, your audience and the complexity of the product you are selling. Consider testing whether short or long-form copy gets more of your subscribers to click-through and make a purchase.


3. Call to Action

Your call to action is one of the most important aspects of your email. They help to increase email click-through rate by making it clear to readers exactly what the next step is.


Using contrasting colours is a good practice for distinguishing the action to be performed. Just remember not to overdo it as it could ruin the whole communication and lead to a decrease in click-through rate instead. Also, consider that it is always a good idea to reference the corporate brand identity colours within an email.


The size of your CTA button can make a difference. The button should be big enough to be obvious, but if it is excessively large, it could be deemed as being overly aggressive, thereby hindering the user experience.

The display on mobile devices is also an element to consider when choosing a button size. Even in this case, testing is best for understanding what is most effective.


By using specific, action-oriented phrases such as ‘Get this guide’ usually performs better in click-through rate compared to simply using a generic term like ‘Read more’. This is to help you understand that how the wording for your CTA is also important for driving clicks and conversions.


4. Improve sending times 

Identifying the right time for email delivery works as a driving force for open and click rates. Well-established hours in the middle of the day are not necessarily the best. It all boils down to the type of business and the target audience. The best times can vary greatly. Generally, B2B companies get better performance during working hours, while B2Cs get better performance at all other times. The best thing is to perform an A/B test to find out the best day of the week and the best time slot.


To sum up, testing is essential in email marketing. By carrying out A/B testing, it can help you uncover high-impact changes in your subject lines, email design and more! See for yourself the transformative changes it will bring you when you start testing!

Read more: 6 Tips for A/B Testing to Increase Conversions


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