I prefer longer subject lines when I compose emails to my distribution lists. I always believed that if I explained what was inside, they would appreciate knowing whether they should open them or not.
The same study I mentioned in “Personalize Your Emails for Better Open Results,” also has info on how long our subject lines should be. And, drat, they need to be short.
Email newsletters with short subject lines (4-15 characters) had the highest average open rate (15.8%) last year. Longer subject lines resulted in lower open rates, though the effect on open rates diminished as the lengths increased.
Click rates also peaked when subject lines reached a minimum. At 4 to 15 characters, click rates experienced a maximum of 2.6%. For subject lines over 16 characters, a normal distribution occurred. Very long subject lines, of over 51 characters, yielded the lowest click rate of 1.6%.
It’s also fascinating to see that the most popular words in subject lines indicate special offers (free, party, sale, coupon) or time sensitivity (news, tonight, weekend, today).
Visit the Mailer Mailer site to see the top 100 words used within subject lines of this study.
How long are your subject lines? What’s your average open rate?