As a company that wants to market to people who receive a lot of email, how do you cut through the noise and get them to at least open your messages? It's all about using the right subject line. That's according to Jerry Jao, CEO of Retention Science, a Los Angeles startup that turns big-data analytics and predictive algorithms into retention marketing campaigns. His company analyzed about 100 subject lines emailed to 3.7 million people targeted across 22 marketing campaigns. Here's what Retention Science learned about the subject lines that entice people to open an email.

1. The ideal length is six to 10 words.

While subject lines using fewer words can outperform those with more, they also leave less room to get an idea across and can be less clear. Plus, more than 10 words usually will drop off the edge of a subject line. "The more emails you send out, the more succinct your email subject lines should be," he says.

2. Use the person's name.

People pay attention when they see their name. Retention Science found a 3 percent increase in open rates for emails using someone's first name versus those that did not.

3. Be strategic about when and how often you send your emails.

Jao recommends no more than two emails per week. And think about when your target demographic is most likely to be in a frame of mind to be open to your marketing. When are new mothers or young professionals taking care of work and when are they taking care of life? When are they most likely to want to buy something? "A lot of professionals who are in the office all day, around 3 or 4 p.m. they are looking for a little bit of distraction from their work and they take a quick break," he says. "So they're looking at what articles are being published or what new products are on sale."

4. Include trending movie and song titles.

One campaign Retention Science tracked included Adele's song "Rumor Has It" in the subject line. "It leaves a little bit of mystique about what this email should be about," he says. "It had a really, really high open rate because people can relate to that song title."

5. Include multiple topics in your email subject line.

For example, "How to live forever: Improve brain function through meditation" or "Check out our latest purses and Louis Vuitton shoes." This tactic increases the chances one of the topics will appeal to a customer or potential customer.

Published on: Oct 5, 2015
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