Email marketing is all about getting the attention of your audience. The first part of your message anyone will see is the subject line, and getting that right is paramount. Many articles give advice on the words you need to use in your subject line, but they often fail to mention the length.
Having all the power words within your content may do you no good if you have a subject line that is too long to read. So what is best: short or long subject lines?
Not All Data Suggests The Same
The biggest problem with determining the ideal subject line length, is that not all the data is the same. It is all dependent on what campaigns are measured and the audience who received those campaigns.
For instance, those sending messages to the B2B sector will find that messages with subject lines of between six and ten words will get more open rates, but click through rates aren’t great. When there are more than 130 characters, the open rates drop significantly but the click through rates increase substantially. Finally, anything over 16 words sees a significant return on both clicks and opens.
The president of ShowMeLeads has claimed that she has found a definitive answer for the length of an email. Research that analysed 260 million emails from 540 campaigns has led her to believe that there is a very specific word count that businesses should aim for.
According to the research:
- Subject lines with between six and ten words generated a 21% open rate.
- Subject lines with fewer than five words were opened on average 16% of the time.
- More than half of emails had between 11 and 15 words in the subject line and generated a 14% open rate.
Marketing Sherpa conducted research to find out whether or not longer subject lines were better than shorter messages. They looked at 9,313,885 emails for their research. Their results were different than those of ShowMeLeads.
Their results were as follows:
- The most popular length for subject lines was between 41 and 50 characters, yet it performed the first worst for open rates.
- Only 6% of emails had a subject line of between 61 and 70 characters, but these had the best open rates (17%).
- Email messages with between 51 and 60, or 91 and 100 characters performed the second best achieving 15% open rates.
Finally, Return Path studied over 2 million emails to evaluate the correlation between subject line length and open rate. Their research also looked at the Pearson’s Correlation value, which suggested that there was no correlation between the length of the subject line and open rate.
However, they still advise keeping an eye on your subject line length. Their research demonstrated that:
- 25% of subject lines were between 41 and 50 characters.
- Open rates were greater when subject lines were between 61 and 70 characters.
- Only when there were more than 100 characters in a subject line did the open rate drop (down to 9%).
Desktop Versus Mobile
One of the important considerations is the device that your email is being read on. Desktop inboxes display approximately 60 characters whereas mobile devices show between 25 or 30 characters. Therefore, if your audience is mainly on mobile devices, then you need to shorten your subject lines, so the call to action or important message is at the beginning.
Email subject length might be an important factor in the success of your campaigns, but there is little evidence to suggest that a longer or shorter one will have a major impact. It might be all too dependent on your primary audience. Therefore, you should consider A/B testing your emails when deciding what works best for your audience.
What subject line length do you use? Have you ever tested it?
Let us know in the comments below.