17+ Email Subject Line Best Practices to Boost Engagement

Rodrigo Fortes

You can have the best email content in the world…but if you can’t engage subscribers with your subject line, all that content is going to go to waste. Instead of opening your emails, they’ll just keep on scrollin’ through their inboxes.

So – how can you write an email subject line that grabs your subscribers’ attention and encourages them to engage with the rest of your email?

Well, there are some tried-and-true email subject line best practices that you can implement, which is the subject of this post.

Below, you’re going to learn 17+ best practices that will help you write effective subject lines, while still retaining your unique voice and style.

These tips will help you generate genuine interest and engagement from your emails, which is essential in a post iOS 15 world where it’s harder than ever to track your subscribers’ actions.

Let’s get to it…

How to improve your email subject lines

Here are 17+ email subject line best practices, presented in no particular order. You might not apply every single tip to every subject line, but you’ll want to try and implement as many as possible for maximum results.

1. Write the subject line first

When you’re setting up an email, it’s easy to create the body content first and then come back to the subject line once you’re finished.

While some people can work effectively that way, it’s generally a better idea to start with your subject line first. That way, you can ensure that you’re not just throwing it in as an afterthought.

Writing the subject line also gives you a chance to directly connect the subject line text to the body text, which can make for more engaging emails in general if the body builds on the subject.

If you don’t want to totally commit before you’ve finalized the body of your email, you can try brainstorming a few variations to start, rather than choosing a final version. Then, you can pick the option that works best once you see how everything comes together.

2. Add some personalization

Instead of sending off the same generic subject line to every subscriber, try addressing each subscriber by their name in the subject line. Or, you can also experiment with other types of personalization, depending on the data that you have about each subscriber.

There’s data suggesting that people are anywhere from ~20-30% more likely to engage with personalized emails over generic ones.

Most email marketing tools make it easy to dynamically insert each subscriber’s name in your subject line. 

If you’re using MailPoet, you can check out our email personalization guide to learn how to set it up. All you need to do is include the relevant shortcode in your subject line. You can also specify a generic fallback in case you don’t have a certain subscriber’s name: