The Science of Subject Lines

As a direct response marketer for nearly 20 years, I’ve learned one incredibly powerful sentence when speaking to clients: “Let’s test it.”

The science in direct response marketing lies in the continual testing and retesting of offers, copy, services, features, ideas, and more. As direct marketers, we do a lot of testing and are constantly striving to find out more about our customers, their needs, their perceptions, and what makes them tick or respond to an offer. Say too much to Ms. Johnson, and you’ll alienate her; say too little or offer no value, and she’ll ignore you. It’s a delicate balance for sure, but one worth pursuing as it can improve response and ultimately give you a competitive advantage in today’s fierce marketplace.

Although marketers have been testing various components of their messaging for decades, the subject line in an email communications program is all too often overlooked. Over the last few years, I’ve seen marketers agonize over and test offers, creative, and landing pages, only to decide on the subject line two minutes before mailing. Not good. I propose marketers place as much importance on the subject line as they do on the other components of their email communication efforts. If you really want to maximize success and create a great first impression, turn your attention to the subject line and test, test, and test again. You won’t be sorry.

Case Study: A Subject Line Test

Recently, a Bigfoot Interactive client embarked on a test of subject line copy, with the aim of improving email open rates and exposing customers to a wider breadth of offerings. This client, a leading consumer packaged goods company, tested a series of subject lines to help promote a diverse line of products from one of its divisions.

With that in mind, the client conducted extensive subject line testing that included the comparison of personalized versus nonpersonalized subject lines across its opt-in monthly email communications.

The result: Personalized subject lines consistently outperformed nonpersonalized ones, yielding, on average, open rates more than 13 percent higher. On a mailing to several million records, this improved open rate created an opportunity for hundreds of thousands of additional consumers to see the offer and potentially respond!

Creating the Right First Impression

With email communications, encouraging the recipient to open the message is half the battle. Creating a winning subject line is critical to success in a world filled with marketers battling for the attention of consumers. Many factors can help shape effective subject lines, but you should start by defining the objectives of the campaign up front.

Defining the campaign goals early in the process will help set the overall agenda and tone for testing. Typical goals may include increasing open rates, improving conversion or sell-through of a particular product, acquiring new customers, or launching a new product or service.

Next, considering your objectives and review all the information you have in your database about your customers, including preferences and data on what kinds of messages they have opened or responded to in the past. This will help you segment your customers appropriately for testing. In addition, any trends or noted patterns should be analyzed to help improve overall success and performance, such as responses by day, time, or offer. Marketers with rich customer profiles and established relationships will have an advantage thanks to the intelligence they have developed over time.

The power of email communications lies in its ability to customize messages on a true one-to-one basis and do real-time testing to maximize return on investment (ROI). Once your objectives are defined and your intelligence is gathered and analyzed, it’s time to test. Create a series of cells and experiment with subject lines. Generally speaking, subject lines that offer value and are benefit-oriented, witty, and personalized generate greater open rates. Messages that are targeted, contextual, and relevant to the recipients’ needs/wants generate higher conversion rates.

As with most media, less is often more. Keep subject lines short. If you have an established brand or product, don’t be afraid to reference it in the subject line and even in the “from” address. Customers tend to be more receptive to messages from the brands they know and trust.

Reaching and motivating your customer to act is no small feat in today’s market. But marketers who better understand their target audiences, test various creative and offers, and don’t ignore the importance of subject line testing will be well positioned to create truly effective email communications — ones that get opened, read, and acted upon time after time.

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