Less is more when it comes to email subject lines

Shorter subject lines prompt more email opens, analysis finds

Austin Clark | 18th Aug 17

Shorter email subject lines seem to be more appealing and prompt greater open rates, according to new analysis.

The analysis, which comes after another research study found that charity emails were less likely to be opened than others, found that subject lines under 21 characters generated a 31% higher-than-average open rate, yet they account for less than 5% of all email subject lines, according to new data from Yes Lifecycle Marketing.

Yes Lifecycle Marketing analysed the subject lines of more than 7 billion emails deployed through its cross-channel marketing communication platform Yesmail360. The study found that more concise subject lines drove higher open rates and more clicks. In fact, those using 10 characters or less accounted for less than 1% of all subject lines but generated an impressive average open rate of 26% – almost double the 14.2% average. However, 45% of subject lines in this category belonged to triggered emails, driving engagement rates up and underscoring the value of message relevance, timeliness and personalisation.

The majority of subject lines (74%) fell between 21 and 60 characters, yet this length saw the lowest open rate at 13.8%. These emails also generated an 8.5% click-to-open rate. In contrast, emails with subject lines under 21 characters received double the unique click rate (2.4%) and a 12.9% click-to-open rate.

Just over a fifth of all subject lines exceeded 60 characters and they generated a 14.8% open rate and 8.9% click-to-open rate.

“While shorter subject lines can sometimes stand out in the inbox, especially on mobile, length is only one of the many email components marketers should take into account when developing their campaigns,” said Michael Fisher, president of Yes Lifecycle Marketing. “The key is still to give subscribers enough information up front to encourage them to open – either through a relevant, personalized subject line or through one that piques interest and appeals to consumers’ curiosity.”

Additionally, the analysis found that only 2% of all emails sent in Q2 2017 included personalisation in the subject line; yet these emails generated 50% higher open rates than those without personalisation.