The Best Email Subject Line [INSIGHTS]
A new ReturnPath study is contradicting some widely held beliefs about consumer preferences and behavior.
The study found that "clickbait" subject lines were among the least effective of the 10 types examined. For example, the use of "Secret of" resulted in a 8.69 percent decrease in read rates compared to messages containing similar content but using different subject lines.
What ReturnPath's analysis reveals is that benefit-based subject lines, which could feature superlatives such as "fastest," were better at getting consumers' attention. In fact, using "fastest" coincided with 5.3 percent higher read rates than comparable messages under different subject lines. On the whole, Return Path's study found that read rates for urgency-based subject lines “limited time,” “last chance,” and “expiring” were also elevated.
“Subject line optimization presents one of the clearest opportunities to apply advanced analytics toward understanding and significantly increasing marketing performance,” said Return Path President George Bilbrey. “By analyzing extremely large data sets collected across the entire email ecosystem, based on how real subscribers engage with messages sent from thousands of trusted brands, marketers can quickly, efficiently, and confidently test subject lines to ensure that their messages are read by as many people as possible. As this study demonstrates, the results are often surprising, frequently questioning or even invalidating long-held best practices.”
Return Path also found that two classes of value-based subject lines yielded very low performance - those promoting prices and discounts. According to the study, subject lines containing keywords that identified discounts, including “discount,” “save,” “sales” and “clearance” coincided with lower read rates. Those including pricing references such as “free,” dollar signs, and percentages also accompanied lower read rates than comparable messages with different subject lines.