Donât just aim for an open with your subject line

Ever heard someone say the purpose of the subject line is to get the open? This is short sighted and the purpose and impact of the subject line goes much deeper. The thinking behind a subject line should be more than “what will make someone read this email?”

A case in point is some work I’ve recently completed for Coinks Deals. I’d like to share with you what was learnt about subject lines and how to best communicate with a large dormant database.

Coinks Points introduced a new deals service for their members and wished to provide these deal emails to members who responded to an introduction email about them. Coinks have millions of members, including hundreds of thousands of who had been suppressed from contact for over 12 months. The challenge was how to message to their entire member database, including the dormant members.

The messaging strategy I developed was a four email sequence using a high degree of personalisation to make connection and re-establish trust with members. Several tests were developed to optimise each step of the sequence, testing a variety of elements, including of course subject lines.

As always with testing, the results were insightful and I’m going to focus on one of the subject line tests and what you can learn from it.

For the third email in the sequence to the dormant segment, one of the tests was of these two subject lines:

• Subject A: Are we still welcome in our inbox?
• Subject B: Was it something we said?

The email itself was a short mostly plain email with a few links and a couple of central buttons shown below

The subject line B gave a 67% higher open rate. However, what was interesting to show the impact of the subject line beyond the open was the ratio of clicks on the above two buttons.

For subject line ‘A’ the ratio of clicks on the first button to second button was 6.5 whereas for subject line ‘B’ it was 2.8. Customers with subject line ‘A’ were more inclined to click the first button. The test cell sample size was 12,000 and the difference in clicks was statistically significant.

The difference in ratio was due to the different subject lines, it changed how customers read the message and what they did as a result. In this case “Are we still welcome in your inbox?” prompted the customer to consider this very question and whether their answer is yes or no. Whereas “Was it something we said?” does not prompt the direct question and the more conciliatory tone creates more interest in deals.

In the many tests I’ve run over many clients I’ve time and time again seen that what happens in the email is skewed and changed by the subject line. The subject line should be designed to get the right people to open not the most people, the right people means those most likely to take the action you want. Plus the subject line should frame their thoughtscorrectly.

The subject line is used by customers to self-qualify, if the subject line does not accurately qualify the right people then customers who might have taken action do not open and conversely some open only to find it’s not the right message for them. In this case the risk is customers become less inclined to open again since they found they wasted their time previously.

Summarising two key learning’s:

• When testing subject lines don’t stop evaluation at the open rate, get more insight by looking deeper at which individual links were clicked and the call to action of each, to learn why the subject line created a particular result.
• Create subject lines with the call to action in mind. The power and impact of the subject line goes further than getting the read, it’s about getting the action and not just the read.

This was just one test out of many over a series of four emails. The compounded gain across the whole email sequence was an impressive 190%.

Next time you think about subject lines don’t focus on just getting the open but setting up the right thought sequence for the call action.

Acknowledgements: My thanks to Coinks Deals and Emailvision for permission to publish the results from this work.