Subject lines are one of the first things your subscribers see when they go into their inbox and have a proven and measurable impact on whether they go on to open, click and convert. Which is why so many email marketers spend so much time AB testing their SLs.
As you can see from the chart below, subject line B “Incentivize your email program without devaluing your brand” went into the lead almost immediately, and after 15 days had generated 32% more unique opens and 20% more unique clicks than subject line A “Incentive Programs: Your guide to giving”. The classic approach to AB testing subject lines would be to create 2 (or more) test cells of about 1% of the list, send each cell a different SL; monitor open and/or clicks for a number of hours or until the numbers are deemed to be representative and then send the winning SL to the rest of the list. Case closed!
But wait, life is never that simple; although the test results tell us which SL performed better they do not tell us why. Building your understanding of what works and why should be the key objective of your SL tests. If you rely on your test results alone – and many people do, it is much more difficult to achieve long term and consistent improvements in performance.
3 simple steps to follow
Here are 3 simple steps to follow if you want to ensure you make your subject line tests more meaningful:
Have a clear sense of what you want to improve or optimize
Are you interested in improving opens, clicks or sales. It is not uncommon for the SL with the least opens to generate more click and/or sales.
Own the results
Make sure that whoever conducts the tests goes on the record and documents which SL they predict will win (or lose), and more importantly why.
Aim to develop a methodology for creating subject lines
Do not reinvent the wheel every time you send an email out, which is what happens if you focus on creating the “perfect” subject line; you are much more likely to deliver consistent results if you have a proven and well-tested methodology.