How to Write Effective Email Subject Lines

The subject line is a very crucial element of your email. A great subject line will enhance the chances of your email being opened, while a poor one might cause your email to be marked as spam or deleted altogether. Here are some guidelines for writing a subject line which will enhance your open rates.  

 Choose words wisely

When writing your email subject line, make sure you avoid words which appear spammy. This includes words such as:

  • Today!
  • Online!
  • Shipping!
  • Available!
  • Here!

Such words, especially when accompanied with exclamation marks, are likely to trigger spam filters. This means that your emails might end up in recipients’ junk folders where they may go unnoticed. To be safe, it would be advisable to think of alternative words which would send the same message.

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 Keep it short

Make sure your subject lines are short, concise and captivating. Generally, it would be advisable to have subject lines which don’t exceed 50 characters. This will make it easy for people to read them on even mobile devices. Use letters, spaces, punctuation and numbers to create an intriguing subject line which will make your recipients want to see the contents of your email.

 Learn from your own experience

Your own experience in handling email can be a good guideline of what works and what doesn’t. Visit your own email account and check the emails contained in different folders. Which emails did you delete without even opening? Which ones did you actually read? Pay attention to the topic of subject lines, word choices or anything else that might have influenced your actions. This information will give you an idea of how to write more effective subject lines.  

Show the benefits

Many people receive numerous emails in their inbox on a daily basis, each competing for their attention. Before opening an email, people would first want to know what’s in it for them. How will they benefit from opening and reading your email? Your subject line should make it clear what readers will gain from opening the email. In addition, you can also tell them what action you want them to take. For instance, ‘Purchase now and get a 40% discount’. You are telling readers to buy now and benefit from a 40% discount.


You can test the effectiveness of your emails by running an A/B test. Start by dividing your email list into two groups; A and B. Write a subject line for group A, and a different one for group B. Send an email to both groups with the same content in the body of the email. Observe to see which subject line produces a higher open rate. This will give you an idea of what kind of subject lines would work in future.

The subject line can make or break your email campaign. Learning how to use the right words will greatly improve the opening rate for your emails.