Why Testing Email Subject Lines Isn’t Optional

by | Oct 19, 2011 | Best Practices, Blog, Blog Archive, Multi-Channel Marketing | 0 comments

By Deb McAlister-Holland

Marketers understand that email marketing is changing.  Still, in July 2011, 95% of the marketing executives surveyed by The Distributed Marketing blog rated email “somewhat” or “very” effective in delivering results – far more than any other marketing communications channel.

 At the same time, everyone involved in email marketing acknowledges that the effectiveness of an email campaign is easier to measure – and harder to achieve – than ever before.

Younger target groups – the 18-35 demographic – use email less each year, with text and social media becoming more important communications tools in this group. Meanwhile, those over 40 are actually increasing their email use, as baby boomers purchase smart phones that give them 24-hour access to business email accounts.

 What determines whether the recipient opens the message or sends it to the trash? Two things:

  • Who it’s from
  • The subject line

Research on millions of emails says that the “from” name determines whether the email gets deleted or not – and the subject line determines whether or not the recipient opens and reads the message. In many cases, subject lines are actually an after-thought by marketers. The trouble with that is that every email message is three seconds from the trash can – and the subject line is either the first or second thing that the recipient sees. Marketers who spend hours on creative development often spend only a few minutes to subject line development. Build subject line development into the project timeline so that it doesn’t fall by the wayside.

Unfortunately, while everyone agrees on the importance of subject lines, there’s very little agreement on much else. A Google or Bing search for “email subject line best practices” will turn up almost as many different opinions as it does resources.   I get asked about email subject lines nearly every day, so I just published a short “best practices” report that summarizes the current thinking on this topic — with the emphasis on “current”, since it’s very much an evolving and rapidly changing area.  You can download it here

The main takeaway from the report is this:  testing subject lines isn’t optional — it’s mandatory.  And it isn’t mandatory just once or twice, because there is no magic formula that works with every audience, or every product. (Or if there is, I haven’t found it in almost 30 years of running an email marketing campaign every single day — and yes, there was email marketing 30 years ago — in fact, email turned 40 this year.)   Just because something works this week with a particular target group doesn’t mean that a similar subject line will get similar results next week. 

So what do you do?  Test every campaign, every time.  Add the time for testing into your project plan, along with time to segment your lists for a valid test.  Remember that sending subject line A to half your list, and subject line B to half the list is not subject line testing — it’s hedging your bet.

To test a subject line, first send the same email to two different groups, changing only the subject line.  (If you try to test more than one thing at a time, you can’t know what factors affected the outcome).   Then,  send the winning subject line to the rest of the target audience. Maximizing the size of the audience that gets the winning subject line maximizes results.

In addition to the new paper on email subject lines, you can download another recent report I published on email marketing here.  It’s called Email Evolution: The Times Are Changing — New Trends in a Proven Marketing Channel, and includes data collected during 2011 on the best times for campaigns, changes in how people handle commercial email, and other useful information.  I hope you find both papers useful!