5 Tips for Writing Effective Email Subject Lines

The subject line’s job is simple: Get the reader to open the email.

On average, 33 percent of recipients open emails based on subject line, so it’s incredibly important to get it right — because even the most enticing email in the world won’t matter if the reader ignores it.


There’s plenty of insight and data across the web on best practices for email marketing, but I wanted to highlight five key tips to help you write an attractive subject line that will draw in the reader.

Tip 1: Go Easy on the CAPS

Contrary to what some of history’s most prolific spammers believed, writing a subject line in all caps will not guarantee an open. In fact, IT’S A GREAT WAY TO LOOK SPAMMY.

While one or two fully capitalized words alone won’t get caught by the filters, it does edge you ever closer to the dreaded spam folder. Capitalization can be a powerful tool to draw attention where desired, but with great power comes great responsibility. Use it sparingly and professionally. Capitalizing as you would a title seems to be an unofficial industry standard.

Studies have also suggested capitalizing the first letter, like in a sentence, works as well and, sometimes, maybe even a little better than other styles.


  • This is the Most Common Industry Practice
  • This also gets great open rates

Tip 2: Make a List

People like lists. Perhaps it’s the promise of information diced into easily digestible snippets or maybe it feels like zeroing in on the most important aspects of a given topic. Whatever the reason, people on the Internet enjoy consuming information via numbered/bulleted lists!


  • Read the Top 5 Reasons Why Lists Work
    (Did you try to click?)
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Tip 3: Personalize the Message

Personalization in the subject line can be quite a contentious topic. One study from MailerMailer suggests that including names in the subject line may actually be detrimental to open rates. However, the data scientists at MailChimp say that personalizing subject lines to include the recipient’s full name can positively impact open rates.

Aside from names, location is another convenient and beneficial personalization to include in the subject line. The good news is location personalization is universally considered a best practice!

Last but not least, consider tying in current events when relevant to your subject.


  • Bob, are you attending CES in January?
  • Where to find the best BBQ in Austin

Tip 4: Create a Sense of Urgency!

While people don’t like to be yelled at in all CAPS, they do respond well to time sensitive material. The fear of missing out can be a powerful motivator. Key words like “Urgent” or “Breaking” can positively impact open rates. Similarly, creating a deadline for an offer can also improve your click-through rate.


  • Last Chance to Reserve Your Valentine’s Dinner
  • Urgent: Save on crazy socks this weekend only

Tip 5: Keep it Short

Your recipient doesn’t have a lot of time or patience, so when choosing between a personal correspondence, a cookie recipe from grandma, and your company’s promotional email blast, what do you think he or she will click on?

Keeping your subject line short and to-the-point is instrumental to establishing a good first impression with the recipient. The ideal subject line lays out the point of the email and sets the expectations for when the reader opens it. This should all be accomplished in 50 characters or less. The sweet spot appears to be between 28-39 characters.

Get to the point or risk losing the reader. The Internet has a name for subject lines like this, which are far too long. It’s called TL;DR (Too Long; Didn’t Read).


  • 7 Tips for Writing a Concise Subject Line
  • Insight on writing a great subject line

We hope you’ve enjoyed reading about these tips to write a more effective subject line. Follow these best practices and test, test, test. Want more marketing tips? Sign up for the Industrial Marketer newsletter.

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