Is your email subject line optimized for achieving the highest open rate for your given industry? Despite being way, way under the length of a tweet, the sparse subject line can make or break your campaign.
Yes Lifecycle Marketing conducted extensive research to determine the parameters that increase the open rate, examining over 7 billion emails in the second quarter of 2017 alone. The study delved into three areas: personalization, length, and industry. Here’s what they discovered.
Personalized subject lines work
Personalized subject lines generated a 50% increase in open rate and 58% increase in CTO rate compared to subject lines without personalization.
Including the recipient’s name is the most common form, comprising of about half of all subject lines with personalization. Other ways to personalize the subject lines include:
- Mentioning a recently purchased product – Jill, how did you like Nature Made’s Probiotic Supplement?
- Mentioning a reward program the recipient signed up for – Jill, you’re just 50 points away from a free upgrade to our platinum program
- Mentioning the name of the sender – Bob just sent you a smiley face
- Mentioning a recently browsed item – Our probiotic supplement is still in stock
Subject line length—under 20 characters! (on average)
Ideally, subject lines should be under—gasp!—20 characters to optimize for mobile. About 75% of subject lines are between 21 to 60 characters. The open rate averaged 13.8% for subject lines within this range—but 18.5% for those below 20 characters.
Since only about 5% of emails have lines below 20 characters, you may gain some clicks by experimenting in this narrow range.
Industry makes a difference to your subject line
While the figures above pertain to the average of all industries, performance for both personalization and subject line length actually differs depending on the industry.
In the consumer service sector, for example, 21 to 60-character subject lines actually fared better with a 15.6% open rate, compared to 13.8% for those under 20 characters. By contrast, the insurance niche fared far better at a 34.7% open rate for subject lines below 30 characters, compared to 26.4% for those between 31 to 60-characters.
As you can tell, there isn’t a one-size-fits-all approach for optimizing subject lines. It’s industry-specific, and you have to tinker with different character lengths and personalization to determine what works best for your target demographic.
This kind of testing is worth it, though, because anything that boosts your click through rate can boost conversion and, well, you get the idea.