Saying Hello: How to Write Great Subject Lines

Email marketing is key to building and maintaining a strong relationship with your customers. And a great subject line can make or break your email marketing strategy. So let's review the ingredients for an irresistible subject line.

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Why is the subject line so important?

A good subject line cuts through the noise of hundreds, sometimes thousands of emails to get your audience's attention. A great subject line piques their curiosity, leading your audience to open your email. It's important to note that 35 percent of email recipients open email based solely on the subject line. So putting the time and effort into getting your subject line just right is worth it.

Just to make sure we're all on the same page, it's worth stating that your open rate is the percentage of people who receive your email in their inbox and open it. So when more people open your emails, your open rate increases. This is why subject lines are so important -- they are the first point of contact in email marketing with your audience.

What's a good open rate?

Square's marketing data points show that the average open rate for automated email is 32 percent and the average open rate for blast email is 16 percent. Know that if your open rate is 20 percent or above, you're doing quite well.

What makes a subject line successful?

Just like your grandma's recipe for her famous apple pie, there are many contributing ingredients to a successful subject line. Unlike your grandma, we're willing to share all the ingredients (What is that last ingredient she uses? Is it vanilla? Cinnamon? Salted caramel? We may never know).

When you're writing your subject line make sure that it is optimized for mobile use, since more than 70 percent of people check and read email in a mobile app. Keep things short and sweet so they're easy to read on a screen - 50 characters or fewer is best.

How can you improve your subject lines?

Remember to segment your list so that the right people are getting the right message and therefore are more likely to open your email. When you're writing subject lines, remember to create a sense of urgency, and use action-oriented verbs and numbers. For example, 'Last call! Use your 50% off coupon before tomorrow' hits all the tips and uses 50 characters.

How can you find out what subject lines are most successful?

You can see your open rates in the Square Marketing dashboard. To understand what type of subject lines resonate best with your customers, look for trends over time. If a subject line mentions a sale or discount, does that tend to drive higher open rates? Or is it new products, or events?

The more you send and study subject lines, the more you'll know about your audience and what they prefer, which can only help when you're writing your (outstanding) subject lines.

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