Email Subject Line Research, Examples and Tips to Increase Your Open Rates

By eleventy marketing group

Increasing Email Open RatesDespite the vast and infinite expansion of the online marketing universe in the past decade, email remains one of the top digital tools for organizations across the board. Email also sits at the top of the marketing hierarchy when it comes to return on investment (ROI).

As reported by Direct Marketing News, the 2015 DMA Response Rate Report found email led all digital channels in both response and conversion rates: “Campaigns conducted with house lists achieved an average 30 to 32% ROI. Those done using prospect lists achieved 15 to 17%.”

While we know email can be incredibly effective and most organizations are using it in some form or another (whether sending out monthly newsletters or daily deals), there is still a lot of room for improvement. And that all starts with getting more eyeballs on your emails.

We’re talking open rates. Before your email can be scanned, read or acted on, it must be opened. Open rates are the digital equivalent of someone opening the door and agreeing to listen to what you have to say. They’re where the opportunity begins.

So what can you do to increase your opens? In today’s post, we’ll explore that topic—providing you some data, examples and tips to improve your email open rates.

3 Common Questions About Crafting Email Subject Lines

When it comes to subject lines, here are a few of the questions organizations often have:

1. What is the ideal length for an email subject line to get the most opens?

There’s been a ton of research, chatter and debate over the years about the role subject line length plays in email opens. Some will tell you there is an ideal subject line length while others will tell you length has no impact on opens whatsoever.

We probably fall somewhere in the middle on that one. While length certainly isn’t as important as crafting a strong subject line, shorter is almost always better in our opinion—especially with the compacted subject line previews people get on mobile devices.

This chart from Marketing Sherpa looks at over 9 million emails and provides a good example of varying subject lengths and their similar effectiveness. But most can agree (and this chart shows) that too long is a bad thing. Most email providers only allow up to 130 characters to display in the subject line. It’s probably not a good idea to ever cross the 100 mark.

Email Subject Line Length and Average Read Rate

2. How many words should you use in your subject line?

Word count may actually be more useful than character count when assessing effective versus ineffective subject lines? Though, again, a well-crafted subject line will probably override word count any day.

When it comes to the ideal number of words to use in a subject line, the results of this 2014 study from Retention Science provides some good info based on an analysis of over 260 million emails. As shown in the chart below, they found that the sweet spot for subject line word count was 6-10 words, with those emails generating a 21% open rate.

Email Open Rate by Subject Line Length

With a 15% open rate, 0-5 words came in second (though we would never recommend going with a zero-word subject line). Retention Science notes that 11-15 words—which came in third place—was the most common length of emails analyzed in the study, with 52% of all subject lines coming in at that length.

Our advice when it comes to subject line length, forget characters and aim for 4-10 words. Unless you’re stringing a lot of really long word together, that should probably make at least the bulk of your subject line appear optimally on most devices.

3. Will personalizing your email subject lines make a difference in opens?

Personalization is the name of the marketing game these days. With more data being collected than ever before, today’s customers expect you to know them. So does personalizing the subject line of an email lead to more opens?

The short answer: Absolutely. Something as simple as putting a person’s name in the subject line will increase the likelihood they will open an email. Again we go to the data: This time it’s a study “developed for Marketing Sherpa based on Experian Marketing Services’ quarterly email benchmark analysis from client brands within the United States and Canada.”

As you’ll see in the chart below, this study found that including a person’s name in the email subject line boosted open rates by a very significant average 29.3%. Though you’ll also see from the chart that those numbers varied greatly across industries.

Email Personalized Subject Line Open Rates

Based on this data it seems like a no-brainer to personalize email subject lines to include recipient first names. A few quick caveats here:

  • In order to include personalized subjects, you must have first names for your email list. If you’re not currently collecting them, you might want to start.
  • You have to ensure your data is accurate. Send an email to a person with the wrong name and they’re probably gone forever.
  • It’s uncertain what the impact of this would be if it’s done on a repetitive basis. Will a person respond as strongly to the second and third personalized subject line they receive from you? Certainly worth testing.

Additional Tips for Upping Your Email Open Rates

Who your email comes from may even be more impactful on open rates than your subject line. Having it come from an actual person’s email address rather than a generic one (i.e., one that starts with “[email protected]”) is always the more effective route to go.

Your list may be the most important factor to email success. Make sure you have a list of good email addresses, consisting of people who want to receive your emails. If you’re emailing people cold rather than working with a list you’ve cultivated and nurtured, expect your opens to be much lower.

Tailoring your email content—including your subject lines—to recipient preferences can also have a big impact on opens. If you know what people like and what they click on, you can use that information to better speak to their individual needs.

Frequency is a factor as well. Emailing too much or inconsistently can hurt your open rates. Over-emailing is definitely an invitation for people to hit the unsubscribe button. Monitor your frequency carefully to make sure you’re not losing people. And give people the option on your unsubscribe page to choose their preferred frequency.

Bonus: Examples of Exceptional Email Subject Lines

A great subject line is like a great headline—it draws you in and compels you to want to learn more. Oftentimes the best way to craft an awesome subject line is to see one. As a handy resource, here are links to some posts where you can find examples of great subject lines: