Have you ever received an email and were blown away by how great it was? Well, besides good design and well-written copy, that email campaign had probably gone through an A/B testing, also known as split testing, at least once or a couple of times. A/B testing is when you split your email list up into two group and have two version of an email and send each group one version of an email.

The A/B test is a way to let you send two slightly different emails to your audience so that you can obtain information on which triggered the most engagement and then use the most effective email campaign to send to the rest of your email list. That being said, you don’t have to stick to just two list groups and two versions of an email campaign. You can split them up into however many groups (as long as it’s random) and as many versions of an email as you want (as long it matches the number of groups), but we think it’s best to start with two. Before we go over which email elements you can test out, here is a key guideline to follow for effective email A/B testing: Only test one element at a time.

For example, if you decide to test two different email subject lines to see which one performs better, just stick to subject lines. Don’t try to test out the subject lines and switch up the content at the same time, because when the results come in, you won’t know which change made the difference.

What to Test: Send Time/Day

One of the main concerns amongst email marketers is timing. What is the perfect and most efficient time to send out emails? Delivery time has a huge impact on whether someone sees your email, clicks through, and converts. Learn when your subscriber is most likely to open your campaigns.

Subject Line

Different subject lines are one of the easiest and most basic methods of email A/B testing. There are a couple of different ways you can go about testing out subject lines.

Personalized – Whether you want to include the recipient’s name or other personal information about them in the subject line to enhance relevancy is up to you. According to an article on Invesp, personalized subject lines are 22% more likely to be opened – but you can test it out for yourself.

Length – MailChimp advises to keep subject lines short while CoSchedule’s longer subject lines received higher open rates.

Details – Simple or straightforward? Will a subject line telling the recipient what’s exactly in the email get them to open it or will a vague subject line pique just enough interest to get it opened? Here are more subject line A/B testing ideas.

From Name

This is also known as the sender name and display name and tells your recipients who sent them the email. This can be the first thing that people notice, even before the subject line, and as they say, first impressions stick. Here are the 3 most commonly used “from names” –  we don’t recommend using the last one. You can read more about why you shouldn’t use a No-Reply as a from name/address here:

Brand Name

Specific Person’s Name



Create different versions of your content to see which gets a better response. You can test small content changes like the email headline or big ones like completely changing the promotion offered in the email. For example, you can offer a discount to group A, and a free gift to group B.


Your brand can experiment with different ways to present your CTA. For example, you can change the wording used, adjust the size and color or the CTA button/font, and test different places to position the CTA in your email.

There are many different ways to A/B test your email campaigns. Make sure to keep track of all the elements you test so you can learn from them and refer back to them for future email campaigns. Email A/B testing is a great way to optimize your email marketing and shouldn’t be skipped. Find the testing elements that work for you and dive in. For more email marketing advice, feel free to call US Data Corporation at (888) 578-3282.