Email Marketing: The Importance of Split Testing

Email marketing without a baseline is taking a shot in the dark.  Continuing to forge ahead with email marketing without measuring how successful your current copy, layout, design and subject lines have been performing is asking for marginal to no results.  Put your methodology to the test with split testing.

Split testing in email marketing is not a profoundly new concept, but I am consistently surprised by how many of our clients follow the status quo without understanding that a minor tweak could significantly improve their email marketing performance.

This is not just theoretical, below are a few examples of how I have used split testing  to increase our email marketing performance.

Email#1 – Testing HTML Email Design

Which HTML layout would drive you to click through to the offer?

Option A – Basic Design with Expert Picture


Option B – Strong 2 Column Layout



While both of these HTML email design layouts have been used in the past, we were able to leverage the best of the two designs through recognizing Option A produced a 6% greater click-through rate than Option B.  The open rates were similar, but remember open rates can be deceiving because many email clients automatically open or will register back as open without the contact actually clicking on the email.

Email#2 – HTML vs. Plain Text Emails

Consider using plain text personalized emails over the heavy graphics and code used for HTML emails.  The personal touch can break through the clutter in today’s marketplace.  When split testing the same copy and subject line between an HTML email and a plain text email, the plain text email outperformed its competitor.

Do you prefer to receive HTML or plain text emails?

Option A – HTML



Option B – Plain Text


The results from this split test were resounding.  Option B boosted a 51% greater click through rate than its Option A HTML counterpart.  Personalizing your emails to come from a living, breathing individual instead of a computer generated email blast can mean the difference between connecting with your potential clients and missing the mark completely.

Email#3 – Subject Line Testing

Subject line testing is one of the easiest and most impactful tests one can perform. MarketingProfs will tell you there are easily 7 Dirty Words You Can’t Use in Email Subject Lines and Easily 100 More You Shouldn’t Use Either. Email subject lines can affect more than your open rate and click through rate…it can actually affect your deliverability.

Does a final offer peak your curiosity?

Option A – Last Chance



Option B – Register



Letting your prospects know this is the final opportunity for the offer always peaks their curiosity; they need to know what they are potentially missing out on.  As you can imagine Option A outperformed Option B by a 28% greater click through rate. This is significant when it could be your only foot in the door.  Subject lines should taken seriously, not just an afterthought of the email message.  Consider your subject line the title of your self-published masterpiece…give it some thought and test, test, test to ensure it becomes a best seller.

Remember…Split Testing is for Everyone

Just when you think you have the right formula for email marketing try a few more split tests; it can only reinforce your methodology or make it better.  For more resources on split testing and email marketing check out these resources:





Image Source: eConnect Email Marketing

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