Email Marketing Case Study: Why Your Subject Line Matters

Dec 31, 2013 | Email Marketing

According to Direct Marketing Association, 66% of consumers have made a purchase online as a result of an email marketing message. Are you utilizing email marketing for your business?

Email Marketing Case Study

According to Direct Marketing Association, 66% of consumers have made a purchase online as a result of an email marketing message. Are you utilizing email marketing for your business? Whether you’re currently using email as part of your digital marketing strategy or you’re just thinking about getting started, this case study will help you to write better subject lines. The following case study comes from an email campaign we conducted on behalf of one of our clients. We believe it sheds light on the importance of both a powerful subject line and A/B testing. Some of the words have been changed to protect our client’s privacy.

Why Your Subject Line Matters

To begin with, let’s explain why your subject line is one of the most important pieces of your email. Without an enticing subject line, no one is going to click through to the contents of your email. The subject of your email is your first, and often only, opportunity to get readers to open your email. Thus, you must determine what your readers want and let them know you are going to give it to them in under 50 characters.

Tips for writing a good subject line (MailChimp):

  • Keep it under 50 characters
  • Avoid the words “Help”, “Percent Off”, and “Reminder”
  • Do not title newsletters the exact same thing each month (i.e. September Newsletter)
  • Offer timely information (i.e. This Week Only)
  • Speak directly to the reader using the words “You” or “Your”

The Importance of A/B Testing

Understanding what works best for your specific audience can take time and require some research. This is where A/B testing comes in handy. If you use MailChimp or another compatible platform for email marketing, utilize the A/B subject line testing feature. With this feature you can specify two subject lines and the system will equally divide your list into two random groups. That is exactly what we did for our client in the following case study.

Email Subject Line Case Study

The client that we conducted the case study for is a Business to Consumer client (B2C) selling consumer products at a national level. Their target audience is adult women.

When we set up their first campaign, we weren’t sure what the readers were most interested in receiving. The email was going to include one featured blog, 3 supporting bogs, a coupon, and a chance to receive a free product by submitting a story. The blogs are all written by the brand and focused on both topics related to the brand and general lifestyle topics that appeal to women.

We debated whether we should advertise the free products and coupons in the subject line, or whether the women would be more interested in the blog topics. Here are the two subject lines we came up with (words in brackets have been replaced for privacy reasons).

Subject Line A (Group A) – The Difference between [Breast Cancer] and a [Cyst]

Subject Line B (Group B) – This Month: [Product] Coupon and [Beauty] Tips

We sent this email to 5 separate lists, all split for A/B testing. For every single list, subject line A out-performed subject line B in almost every category.

List 1

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List 2

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List 3

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List 4

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List 5

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The Results

Subject line A (Group A), The Difference between [Breast Cancer] and a [Cyst], had a greater number of total opens for 3 of the 5 lists, a greater number of total clicks for all 5 lists, and a higher clicks per unique open rate for all 5 lists. The bounce rates were almost equal across the board as were unsubscribes. The only metric subject line B (Group B) did better on was successful deliveries and even then, there was less than a 1% difference for each list.

As you can see from this case study, the subject line that focused on a brand-related story was much more appealing than one offering a free coupon and beauty tips. Below are our theories for why this was the case:

  • These women opted in to the list for useful information, not freebies
  • Free coupon subject lines appear spammy (and may even go directly to spam folders)
  • “This Month” signifies a newsletter and people often assume they will receive repetitive information with newsletters
  • [Beauty] Tips sounds vague and not very enticing, whereas [Breast Cancer] and [Cyst] are specific, making them more relevant to the target audience

From this study we have learned how to target the specific demographic for this client, what works, and what does not. We hope this case study will shed some light on what could work for your company and encourage you to try out an A/B testing campaign.

Email marketing is a vital aspect of any digital marketing campaign, boasting a high ROI and lead generation rate. Contact Informatics Inc. today and we can help you create a successful email campaign.

photo credit: Maria Elena via flickr cc

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