Clever Transactional Email Subject Lines….Why Let Marketers Have All The Fun?

March 05, 2019
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Clever Transactional Email Subject Lines….Why Let Marketers Have All The Fun?

Email marketers talk a lot about subject lines because they are one of the keys to getting email newsletters and promotions opened. Marketers love to test variables like the length of subject lines, calls-to-action in subject lines, and even emojis–all in the spirit of increasing subscriber engagement.

On the other hand, transactional emails, like purchase receipts and account alerts, tend to have more dry, to-the-point subject lines.
But who says you can’t have fun and experiment with transactional email subject lines too?
I recently received an overdue item alert email from the Denver Public Library.

Apparently, I had held on to the BlacKkKlansman DVD for too long (if you haven’t seen this movie yet, you should!).

Instead of the normal “Your item is overdue” subject line, the library decided to play with their subject line a little:

There is an empty spot on the shelf and in our heart.

Well if this won’t entice you to open an email, I don’t know what will! An empty spot in your heart? Tell me more, how can I help?!

The email went on to read, “The library and other borrowers are missing your overdue items. Please bring them back; they can be returned to any Denver Public Library.”

I love that the Denver Public Library allowed themselves to have fun with their transactional, historically pretty dry email message. It definitely piqued my interest, got me to open the email, and ultimately take action (yes, I was guilt-tripped into returning the DVD the next day). I hope that empty spot in their heart has now been filled.

Transactional subject line ideas and examples

I think this same concept can be applied to other types of transactional email too. Maybe a password recovery email could start with, “Lost something? We can help you find it” or “They say an elephant never forgets. People do.”

A purchase receipt email subject line could read something like, “You made a good choice.” or “Your friends are going to be so jealous.”

Notice that the above subject lines are shorter and get to the point while evoking some curiosity. Are you ready to get a little more creative with your subject lines? While there aren’t any hard and fast rules for writing subject lines, there are some tried-and-true best practices that we’ve seen be successful.

To help you think creatively, we’ve also compiled some good subject line examples that resonated well with us.

Of course, a fun subject line won’t work for all types of emails or subscribers. It’s important that you don’t deviate too far from the brand personality you have already established, and that you don’t alienate subscribers.

Most importantly, make sure your subject line message is clear and easy to understand. Each subscriber base is different, and the only way to know what works best for yours is to test, test, test!


I encourage you to try something new with your transactional email subject lines. Your subscribers may appreciate seeing a little more of your brand personality shine through!

For more information and best practice tips for both transactional and marketing email, check out our Marketing and Transactional Email: How to Build an Integrated Program best practice guide and head over to SendGrid's transactional use case page to see how you can build or optimize a transactional email program.

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