How to optimize your email subject line

Email subject lines are a crucial component of email strategy. It’s the first thing your subscriber sees when reviewing all of the emails in their inbox. There are many ways to approach composing subject lines that will grab your audience’s attention.  


Start off with some basics.

Use your brand or company name.

Even if you’re using a recognizable From Name and Reply address, sometimes it helps to see your brand name in the subject line as well. This works best for short brand names. Longer brand names start to cut into your subject line real estate.


Get to the point.

While there is no limit to how long your subject line can be, try to keep it to 50 characters or less. Short subject lines (less than 35 characters) tend to outperform long ones in open rates because these are easier to consume on a mobile device. Long subject lines tend to receive better clickthrough conversions due to the additional information provided up front. A happy middle range is about 50 characters.


Relate to the email content or offer.

Get detailed about the offer, benefit, or general content. Use longer subject lines to get specific enough for subscribers to decide how relevant the message is to them. The more relevant a message is perceived, the more likely a subscriber is to take action once the email is opened. Try to avoid words or phrases like Big Sale, Great Opportunity, and Don't Miss Out. Put these in your preview text or preheader instead.


Follow a naming convention for specific emails.

Subscribers will start to learn what to look for in your email subject lines. Maintain consistency with newsletters or performance reminders by following a subject line naming convention.


Review your analytics.

Look at the analytics on your blog and website. On the most popular pages pull out subject lines and then do some A/B testing to see what works.


Personalize it.

Use Data Fields to personalize subject lines. Learn more.


Test what works.

A/B test long versus short subject lines. Test subject lines for both response and spam filter tolerance level. Corporate email filters can be the most stringent with your emails. Test emails internally to make sure emails are getting through as expected. Learn more.