With the abundance of emails people receive on the daily, subject lines play a vital role in whether or not a customer opens an email. In order to avoid an immediate delete from people mindlessly scrolling through their inboxes, subject lines should be relevant, enticing, and eye-catching (the list could go on and on) all while staying within the limited confines that a subject line provides.

Although there’s no specific formula for crafting the perfect subject lines for maximum opens and clicks since ultimately your customers are a unique group, there are plenty of things you can do to improve your subject line game. On the flip-side, there are also a few taboos you should definitely avoid. Spoiler alert: nobody likes all caps.


  • Keep it straightforward. Subject lines that align with the content of the email perform better than those that don’t… besides, no one likes surprises or a bait-and-switch. In fact, the latter is illegal.

  • Convey a sense of urgency with a deadline or a call to action. If customers see that an offer only lasts a certain amount of time, they’ll be more compelled to click right away.

  • List it. In the listicle world we live in today, email is no exception. Customers respond well to hard numbers and lists, like “10 reasons you need a blanket scarf.”

  • Personalize. By including a first name, a specific location, or current event in your copy, people will feel like your emails are from an actual human and not a robot.

  • Use emojis. Including emojis in your subject line can increase the effectiveness of your email by up to 70%.

  • A/B test your ideas. You’ll never know which subject lines are working best unless you test them against one another.

  • Learn about your customers. What works well for one company may not work for yours.


  • Allude to a sale or free item in the subject line if you’re not actually offering a great deal.

  • Write in ALL CAPS. There’s no need to shout.

  • Use exclamations!!!!!!!, Dollar $ign$, percentage signs (%)s, or a combination of any other special characters. These get marked as spam.

In Conclusion…

The most important things with subject lines are to stay true to your customers and brand, and to follow best practices for landing in the inbox. Otherwise, the world is your oyster. While some companies decide to focus subject lines around a specific offer, others go for more creative, humorous copy. Since we can’t all be comedians, an alternative would be to use emojis or pop culture references. Look at what’s trending on Twitter. Listen to the songs that are topping the charts. Stay current and as always, test it.