Subject to Change: Highly Promotional Subject Lines

It used to be that putting “free” or “XX% off” in an e-mail subject line was an almost sure-fire way to increase response rates. But with e-mail recipients growing accustomed to getting something for nothing, marketers are wondering whether such highly promotional terms are losing their effectiveness.

Certainly fewer subject lines are emphasizing these phrases, according to Experian’s “2010 Digital Marketer: Benchmark and Trends Report.” In a study that’s received lots of attention during the past few weeks, Experian found that 20.9% of US marketers used “you” or “your” in their subject lines during November 2009, up from 17.2% the previous November, making it by far the most popular term. In contrast, 12.4% of the November 2009 subject lines used “free,” down from 16.9% the previous year. The use of “% off” declined as well, from 14.2% in November 2008 to 9.4%.

Which is not to say that “free” and its promotional brethren will soon be archaic subject-line terms. 

“More reliance was placed instead on the use of keywords focused on the customer and general words such as ‘sale,’ ‘save,’ and ‘coupon’ to create more curiosity about the offer, enticing subscribers to open,” notes Sara Ezrin, senior director, strategic services at Experian CheetahMail. Even so, “often coupled with other offers and discounts, ‘free shipping’ with a low minimum spend [produced] the strongest unique open and click rates. Percent discounts of 40% and higher had the highest open and click rates of percent-off discounts. More important, stand-alone ‘free shipping’ offers pulled the highest revenue per e-mail.”

The fact is, targeting is just as critical to a subject line’s effectiveness as terminology. “‘Free’ and ‘save’ will compel recipients to open the e-mail, but only if they were targeted correctly in the first place,” says Miriam O. Frawley, president of e-Diner Design & Marketing. That could mean using these promotional terms to convert a prospect into a customer rather than to entice a frequent customer to make another purchase. Then, too, if you’re promoting baby clothes to a parent of teenagers, chances are good that no discount, regardless of how large, is going to result in a sale.

“So many companies use these terms—‘free,’ ‘discount,’ ‘act now,’ and ‘today only’—as calls to action, which may have caused them to lose some of their impact,” says Greg Cangialosi, president/CEO of e-mail marketing specialist Blue Sky Factory. “However, sticking to best practices, if companies are using e-mail effectively and sending targeted relevant messages to an engaged audience, subscribers will look forward to their e-mails, and these terms can still be powerful.”

Cangialosi cites a client that frequently uses terms such as “free shipping” and “huge savings” in its subject lines. “E-mails with these offers and terms have an average open rate of 19% and an average 6% click-through rate,” he says. “Their e-mails with less focus on sales and promotions have an open rate of 15% and a click-through rate of 4%.”

So what’s an e-mail marketer to do? These suggestions might help:

·      Never assume; test. Ezrin advises “constant testing of promotional phrases compared to other subject lines including brand names, personalization of first name, short ‘curious’ language, and so on.”

·      Segment your list and tailor your subject lines accordingly. If you have a portion of your subscriber file that has never responded to “free shipping” in a subject line, continuing to send them free-shipping offers is probably an exercise in futility. Try sending them a brand-oriented subject line instead. Or you may want to limit promotional subject lines to prospects or customers you’re trying to reactivate. “We recommend marketers do data analysis on their subscriber base and look for trends in subscribers’ purchase history,” says Cangialosi, “or the actual behavior of how their subscribers interact with their campaigns.”

·      Don’t use open rates as your sole criterion of a subject line’s effectiveness. For one thing, because the default setting for most e-mail clients is to not display images, “a recipient can interact with an e-mail—click on a link, etc.—but the open may never been recorded,” Cangialosi says. For another, if a subject line generates a high open rate but a lower-than-average purchase rate, recipients may have perceived it as misleading, which could ultimately damage your brand. Besides, what is it that you want recipients to do: open your e-mail, or make a purchase?

·      Use your imagination. “Try being truthful and creative,” says Frawley. “A good headline has always worked to persuade the viewer to read on. Same with e-mails and subject lines.”

·      Keep an eye on your deliverability rates. According to Cangialosi, when a term such as “free shipping” leads the subject line, the messages have a much greater likelihood of being routed to recipients’ bulk-mail/spam boxes rather than to their inboxes.  

·      “Find the balance between branding [your] products and sending offers that will encourage customers to engage and purchase,” Ezrin says. “If a marketer always offers free shipping as part of their value proposition, we don’t recommend wasting the space in a subject line in every e-mail with those keywords. Instead, brand that message heavily in the early lifecycle state… and include reminders randomly throughout the year.”

·      Try mixing things up. There are no hard-and-fast rules as to how often you should use a highly promotional subject line rather than a branding message. Cangialosi says that generally he recommends using the most-promotional phrases “no more than 25% of the time if companies are sending [e-mails] more than twice per week.” But again, it comes down to testing and knowing your audience. “Each list is different, and continuous testing will help each marketer know the best threshold for their list.”