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The Art and Science of Email Subject Lines

Rieva Lesonsky
email subject lines

When it comes to engaging customers via email, good subject lines are essential. Here are a few tips to help you craft subject lines that will keep your emails out of your customers' spam boxes.

1. Keep them short. In general, aim for 50 characters or fewer. If your email subject line is too long, it won’t display fully. Test your emails using different mobile devices and programs to make sure your subject line appears in full.

2. Modify your email subject lines based on what you’re sending. If customers subscribe to your monthly or weekly email newsletter, or you are sending a notice about an upcoming appointment or an update on their account, straightforward subject lines are likely best.

For example, instead of a subject line like “spring is springing up all over” for your gardening company’s May newsletter, consider something more straightforward, like “Louis Landscaping’s May Newsletter.”

3. Focus on benefits. If you are sending a promotional email, you can have a bit more fun with the subject line. However, it’s still important to focus on benefits to the recipient, not the features of what you’re selling. For example, “Save Now on 100+ New Jean Styles” is better than “100+ Jeans on Sale.”

4. Include a call to action. Promotional emails get better open rates when they spell out what you want customers to do: “Order Today, Get Free Shipping,” for example.

5. Proofread carefully. You should always proofread your emails, but subject lines are especially important. It would be embarrassing to have a major gaffe in a 50-character subject line.

6. Stay away from spam. People get so much email that most have developed a sixth sense for spam emails. Read and re-read your email subject lines to make sure they don’t seem spammy.

7. Avoid these words: One study found that including the words “help,” “percent” or “reminder” in subject lines had a negative effect on open rates.

8. Include your company name. It may seem too direct, but including your company name in the subject line is essential for showing customers that the email source is trustworthy.

9. Test and retest. Of course, what really matters is not what other studies found, but what your results are. It’s easy to do A/B testing of email subject lines to see what gets the best results. What works for your customers? That’s what you need to focus on.

10. Mix it up. Finding subject lines that work doesn’t mean you should use the same ones over and over. The ideal subject line has the perfect mix of familiarity (to make the recipient feel comfortable) and originality (to spark their curiosity to open it).

About the Author

Rieva Lesonsky is CEO of GrowBiz Media, a media and custom content company focusing on small business and entrepreneurship. Email Rieva at, follow her on and visit her website,, to get the scoop on business trends and sign up for Rieva’s free TrendCast reports.