4 Types of Email Subject Lines & Why They Work

What if you knew you’d be able to increase the number of opens on your next email campaign?

We can’t tell the future, but we can use statistics and case studies to narrow down what subject lines are driving opens in 2019.

Brandetize has tried and tested dozens of email subject lines and found the four subject lines that are working right now.

Here are the four types of email subject lines to add to your email sequence to increase your open rate.

4 Types of Subject Lines to Increase Your Open Rates

1. A Subject Line That Sparks Curiosity

What information do you have that your subscribers are dying to know? For example, as an agency, our subscribers want to know how to grow an online following, sell more products, and be better marketers.

So, our curiosity subject lines resemble this:

How Did This Marketer Get A 15% ROI on an Email Campaign?

2. A Subject Line That Calls Directly To A Specific Consumer Want

The email behind a direct subject line is similar to the email that fulfills somebody’s curiosity. The only difference is how you’re tempting them to open. With the curiosity subject line, you’re teasing them to get them to open the email. With a direct subject line, you’re telling them exactly what’s inside that email.

For example,

The Email Campaign Course For Small Business Owners

This Program Will Help You Write A Book

3. A Subject Line That Stresses Urgency

Urgency is a marketing strategy that worked for decades. When there’s a limited number of products available or when a discount is about to expire, consumers make a split second decision to purchase.

What happens when you wait in line at the grocery store, see a candy bar next to you and start thinking if you want it or not?

You only have a minute or so to decide if you want it or else you’re going to move up in line and lose your access to it. There’s a reason these candy bars have been placed next to the register, urgency works.

Here are examples of urgency email subject lines:

Closing At Midnight—6 More Hours For The Email Subject Line Course

1 More Day For Half Off The Email Subject Line Course

4. A Subject Line That Promises Proof Of Result

In a world of clickbait, people love the idea of actually getting the information they clicked for. Similar to the direct email subject line approach, proof of result subject line tells the reader exactly what they’re in for by using numbers, statistics, or case studies to prove the result.

For example:

This Email Subject Line Got 157,839 Clicks

These subject lines are working best for our clients right now, but we wanted to do more.

We asked ourselves, can we get an even higher open rate?

9 Subject Line Details That Improve Clicks

We started to test variations of these subject lines. We added in the customer’s name, provocative statements, and A/B tested what numbers drove more opens. These variations turned into the cherry on top of our email marketing sundae.

Here are nine details to add to your subject lines to get more opens.

1. Time Your Emails for Your Audience

Test what time your audience is most likely to open an email—morning, afternoon, or night. Depending on your audience, there are going to be one, or several, sweet spots when your emails have the highest chance of being opened.

According to a Campaign Monitor study, 16% of emails are opened between 12am-8am (before work), 7% are opened at 1 pm (lunchtime), and 24% are opened from 6pm-11pm (after work).

2. Use the Customer’s Name

Emails with a personalized subject line, like the addition of the customer’s name, have a 26% higher chance of being opened.

For example, here are some personalized email subject lines that have worked for us:

Abby—are you using the right email subject lines?

You’re one of our favorite customers, Brendon

Do you want a 70% discount on your membership Alisha?

3. Be Positive In The Morning and Negative At Night

People are more susceptible to positivity in the morning and negativity at night. Emails with a positive subject line are more likely to be opened in the morning compared to night time. The same works the other way—emails with a negative subject line have a higher open rate at night compared to the morning.

In the morning, people prefer emails like, “10 Reasons Why Email Marketing is Thriving in 2019”.

At night, subscribers prefer to open emails with the subject line, “10 Sad Statistics About The Decline In Direct Mail Marketing ROI”.

4. Be Provocative

What can you say that would grab the reader’s attention? Being provocative doesn’t mean you need to start spreading conspiracy theories. Your goal is to make the reader stop scrolling through their unopened emails and think— “No way…”

For example, a provocative email subject line to send to an email marketer would be:

Your Email Marketing Strategy Is Wrong

If Your Agency Is Doing This—Your Email Campaigns Will Fail

Sending This Email Subject Line Means You’re A Bad Marketer

5. Use Seasonality

Personalizing email subject lines to holidays and events can make people feel less like they’re in a marketing funnel and more like they’ve been sent an email they actually want to read.

Seasonal events to create subject lines around include Valentine’s Day, Memorial Day, Labor Day, Halloween, Thanksgiving, Black Friday, and Christmas.

Here are examples of seasonal subject lines that you can use:

This Email Is Going To Be More Romantic Than Your Valentine’s Date Tonight…

BOO! 10 Email Statistics That Will Scare the Pants Off of You

We asked Santa for a better ROI on our Email Marketing Campaign…

3. Use Odd and Specific Numbers

For years marketers have found that using odd numbers and specific numbers drive more clicks and more opens. Blog posts dating back to 2013 talk about the power of odd numbers over even numbers and specific numbers over rounded.

Use odd numbers when writing a list style email.

  • Replace “6 Email Subject Line Examples” with “7 Email Subject Line Examples”

Use specific numbers when talking about larger numbers instead of rounding them.

  • Replace “The 100,000 lead email subject line” with “The 109,534 lead email subject line”

7. Keep The Subject Line Short

People are opening at least 50% of their emails on a mobile device (Emailmonday) which means they can only read about twenty-five characters per email subject line. Using a maximum of 25 characters makes sure your entire subject line can be seen in a mobile inbox.

To see how many characters a subject line is, you can copy and paste it into a Word, Pages, or Google Document. Highlight the text and click on Tools→Word Count. Below the Word Count, you can see how many characters your subject is.

8. Use A Second Subject Line

The second subject line plays off of the first subject line. It’s your second opportunity to convince subscribers to open your email. Using it to really drive the value of opening the email can increase your open rate.

For example, your first subject line can say, “This email subject line generated 109,534 leads” and your second subject line can say, “It was made using this email subject line strategy”.

9. Add Symbols To Stand Out

56% of brands who used emojis in their subject line had a higher unique open rate (Forbes). The top ten most popular emojis to use in your email subject line, according to Hubspot, are:

👉,👇,😉,🎉,🤔,👏,🚀,🔥,🎄, and 👀.

In Hubspot’s The Ultimate List of Email Marketing Stats for 2019, they outlined some key statistics about email marketing.

The statistics that stood out to us, and are the inspiration behind our successful email campaigns, are:

99% of consumers check their email every day.

73% of millennials prefer communications from businesses to come via email.

59% of marketers say email is their biggest source of ROI.

40% of B2B marketers say email newsletters are most critical to their content marketing success.

These statistics are telling us one story, email marketing is thriving. To stay ahead of the curve, we’re using these email subject lines to get more subscribers to open their emails so we can increase our client’s ROI.

The next step in your email marketing campaign strategy is to become a master at writing emails. If you’re going to use these subject lines, your emails are going to be opened. The content inside needs to be branded and high converting.

How do you write a great email? Read our other email marketing strategy article on How To Write A Stellar Welcome Email.

Abby is a Marketing Manager for Brandetize that specializes in all things analytics, data, and email. When she’s not making pivot tables, she’s teaching her puppy Jude how to roll over. She’s working on it.