One key factor that often gets overlooked is the subject line.

It’s the first thing teachers will see and has a huge impact on whether they’ll give your email the time of day or not.

But, how long should they be? Is ‘quirky’ good, or should you opt for something more straightforward? Does personalisation really make a difference? And how much of an impact does your choice make on the unsubscribe rate of an email send?

My answer is often a variation of the mantra that every email marketer swears by: The only way to know for sure is to test. A/B subject line testing is the only real way to find out what is going to best engage your audience, and boost the open rates on your email campaigns to schools.

But even then, where do you start when crafting the best selection of subject lines to test?

To do that, I compiled a list of over 700 subject lines from email campaigns we have sent to schools for our clients, along with their open rates and unsubscribe rates, and categorised each one by type, tone, and personalisation.

The results were a little surprising…

Starting with email type, I assigned one of four labels to each subject line:

Benefits Led: promotes the benefits of the product or service on offer

Offer: directly mentions a special offer in the subject line

Question: asks a question, usually indicating that the answer can be found in the email

Statement: a simple description of what the email is about

Conventional wisdom often claims that questions in subject lines drive open rates, whereas my own anecdotal experience of A/B testing and analytics would suggest that the ‘benefits led’ approach is often the best way to go.

Many clients worry about their email campaigns to schools ending up in SPAM folders if they place an obvious special offer in the subject line, and others worry about being too boring by using a simple subject line.

So, what did the numbers say*?

Perhaps surprisingly, the highest average open rate was seen by the ‘offer’ type subject lines, with an average of 17.70%.

Second were the ‘statement’ type subject lines, with an average of 16.57% opens.

Then it was the ‘benefits led’ subject lines with an average open rate of 13.86%.

And finally, those quizzical subject lines achieved just 11.77% opens.

Next, I checked the average unsubscribe rates for each type of subject line. Those higher open rates are all well and good, but if people are only opening your email to hit that unsubscribe link, it’s not ideal. Again, the numbers weren’t exactly what I expected. Across all four categories, there was virtually no difference in average unsubscribe rates.

So, it seems that ‘offer’ subject lines are the best option when sending email campaigns to schools.

This assertion comes with a word of caution, though.

Offers only work if they seem genuine.

You may be toying with the idea of using something offbeat and quirky… subject lines like that are attention grabbing, which can help cut through the noise of a busy inbox. But is it a good idea for your email campaigns to schools?

On the whole, no.

Finally, you need to decide whether or not to personalise your subject line. This could include the recipient’s name, the school name, or some other piece of relevant data (how about mentioning their subject specialism when targeting department heads?).

Every article you have ever read says that personalisation increases engagement, doesn’t it? This time, the answer is a big ‘Yes!’ Personalised subject lines saw a 10% higher average open rate than those without.

Email engagement rates can rise and fall across campaigns. We don’t always know what is going to work and what isn’t, and even across a sample size this large, there will be a huge number of variables which have had an impact on the results.

Sometimes a subject line that asks a question will be the way to go. And sometimes, personalisation just won’t be appropriate. But if you need a little guidance on crafting a subject line for your next email campaign to schools, this is a great place to start.

*Just so you know, we don’t pluck statistics out of the air here at Buzz Education – every statistic you’ve just read is from detailed analysis of our clients’ email marketing to schools campaigns.