11 Best Email Subject Line Styles to Increase Your Open Rates

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Anyone with experience sending out email newsletters for WordPress will tell you that half the battle is getting readers to open your email in the first place. That’s why taking the right approach to your subject line can make or break your email strategy.

Email conversion strategist and copywriter Val Geisler recommends spending as much time on the subject line as on the email itself. So I’ve assembled some of the best subject line styles to increase your open rates and keep your email strategy moving in the right direction.

1. Emails with numbers and lists

It works for clickbait articles, and it works for emails. People love lists and they love numbers — as long as those numbers are relatively low and easy to wrap your head around. You’ve probably seen email subject lines such as:

  • Top 18 of 2018
  • 9 Common Android Problems and How to Fix Them
  • 2018 By the Numbers

All of these email subjects are real — and they each communicate something tangible and specific. That’s why numbers are so successful — you know exactly what you’re going to get when you open this email.

Emails with numbers and lists promise a certain amount of useful information, and as such, they can stand out from the rest of the emails in a user’s inbox. The tactic is so successful that some brands will even go so far as to make the number and the list part of the name of the email instead of the subject.

For example, “Moz Top 10” sends out a weekly newsletter, but “Moz Top 10” is the name of the sender, not the subject line. This is a variation that might also work for your brand or business, depending on the nature of your email newsletter.

Moz top 10 email subject line

Use this strategy when: You have a lot of information to get across. Lists are a great way to organize that information into a chunk that’s easy to digest.

2. Subject lines designed to shock

As with anything in life, you can get a little attention if you’re willing to say anything. That holds true with email subject lines as well.

If you use a controversial or shocking email subject, it’s likely you’ll increase your open rate. But there are significant risks to this strategy, especially in these politically polarized times. It’s important to weigh the risks carefully before proceeding with this strategy.

Use this strategy when: You want to shake things up and you have email content that is actually shocking. If your shocking subject line doesn’t match the email content and subscribes feel like they’ve been tricked, your unsubscribe rate could go up.

3. Humorous subject lines

Humor is a wonderfully persuasive tool in nearly any setting, but it’s especially true with email subject lines. If you can get your reader to laugh, you’ll probably get your reader to open your email.

Some examples of humorous subject lines include:

  • It’s time for sportsball! (Shirt Woot).
  • You are one with the Star Wars sale, and the Star Wars sale is one with you (Think Geek).
  • Spocking stuffers (Star Trek shop).
Think Geek email subject line

Humor, of course, needs to be used appropriately, so it should never be crass or at anyone’s expense. But it’s a great way of making your brand appear approachable. Humor humanizes you in a way that few other techniques can, so readers feel as though your email is coming from a person instead of a business.

Generally speaking, however, humorous subject lines should still provide some insight into what your email is actually about.

For more: Lessons in Writing Memorable Content from the Master of Wit, Oscar Wilde.

Use this strategy when: Your subject matter could use a dose of humanity and humor, or when you want to personalize your brand in some way. Humor is a great way to relate to your readers.

4. Subject lines that appeal to vanity

We all like to think of ourselves as being on top of our game all the time, more or less. So an email subject line that appeals to the vanity of the reader will often find success. Email subject lines might look like the following:

  • Happy birthday! It’s time to celebrate you! (Red’s Savoy Pizza).
  • Age defying beauty tricks (La Mer).
  • Your butt will look great in these workout pants (Fabletics)

Use this strategy when: You really know your audience — and you know you’re not going to offend them.

5. Short subject lines

When your subject line is short and to the point, you’re taking a gamble. First and foremost, you’re betting that everybody else’s subject lines are going to be long. That means your short subject line will stand out from the crowd.

It’s hard to emphasize how important that can be. Getting readers to notice your email can be challenging given that everyone these days is sending out emails. Your reader’s inboxes are jam packed with reading material, most of which they never open.

A short subject line could be your best bet to stand out. Examples include:

  • AS IF (The Reformation).
  • Who Does That? (Buzzfeed).
  • Save $100 (Rosetta Stone).
  • Upgrades Ahead (Etsy).
  • Sicily’s simple pesto (Christopher Kimball’s Milk Street)
Short email subject lines

You can see how each of these subject lines conveys a significant amount of useful information in as little space as possible. You know, more or less, precisely what’s inside each of these emails before you open it. That you stand out from the rest of your reader’s inbox means you’re maximizing your chances for an increase in your open rate.

Use this strategy when: Your email topics in the past have been longer, or when you have a topic that fits a punchy subject line.

6. An appeal to emotions

We all know that emotions are powerful motivators. How you feel can often influence how you behave, and that’s certainly something to think about as you’re crafting your email subject line. This emotional appeal could come in many forms — sometimes helping to uplift your reader and sometimes appealing to fear or sadness.

These appeals to emotion aren’t always bad, necessarily. When you spend some time thinking about what drives your customers or your audience, you can accurately pinpoint ways to use emotions to motivate that audience.

Some examples include:

  • Will you put down your phone to save a child’s life? (Unicef).
  • Learn a language with only 5 minutes per day (Duolingo).
  • Feed your guests without breaking the bank (Pizza Hut).

You can see how these appeals vary based on the emotion provoked. The Unicef subject line appeals to a sense of guilt or sadness. The Duolingo subject line appeals towards one’s own inner hopes of self improvement. And the Pizza Hut subject line appeals towards your sense worth as defined by your ability to host.

These are all very different, very complex emotions. But if the subject line lands on an emotional level, you’re much more likely to open the email in question.

Use this strategy when: The data behind your message is a little dry or overwhelming. Emotion is a great way to make data relatable.

7. The straightforward email subject

Sometimes, the best way to get someone to open an email is to be as straightforward as possible about what’s inside. This is a common tactic when:

  • You know that your reader wants to know the information contained in the email.
  • The information contained in the email serves a business or transactional purpose.
  • The information inside the email applies personally to the recipient of the email.

That said, a straightforward email subject — simple and to the point — may also be an effective persuasive technique if deployed under the right circumstances. For example, you could easily email a customer or group member about a new promotion in much the same way you would email about a pending transaction.

You just want to ensure you don’t do that terribly often or thoughtlessly. You don’t want your customer to feel as though he or she has been duped, and you don’t want to alienate your readers by deploying this strategy too often.

Some examples of straightforward email subject lines include:

  • Your statement is ready to view
  • Thank you for registering for _____
  • Your item has shipped.

Use this strategy when: You have straightforward information to deliver (and when the customer is expecting that information).

8. Putting discounts right in the email subject line

Sometimes, you just want to cut right to the chase. That’s especially true when you know that the only reason your subscribers keep opening your emails is for the discounts (this would one time when market research would be very useful). In these cases, you can put whatever discount you’re offering right in the subject line.

9. The “time is running out” approach

There’s no harm injecting a little urgency into your email subject lines. After all, it doesn’t take all that much time to actually open up and read an email. So if you can make it seem as though it’s now or never, your reader might actually expend the few seconds necessary to open and read your email.

But it better be worth it and it better be accurate. Rosetta Stone, for example, has become something of a running joke because it advertised offers that were expiring and would never come again — only to re-run those same basic offers just a few weeks later.

For this example below, DesignModo uses the subject line “Halloween Discount! Slides Framework 30% OFF.”

Halloween discount email

You don’t want to lose the trust of your readers. So this approach is usually reserved for short-term sales, discounts, and coupons. Some examples include:

  • Your 15% off is about to expire (Barnes and Noble).
  • Earn double points today only (Jersey Mike’s Subs).
  • Last chance to save 20% on our highest rated meat-cleaver (America’s Test Kitchen).
  • Notice: Your Prime Pantry credits are expiring soon (Amazon).

You get the idea. By creating a sense of urgency, you can give readers even more of an incentive to open your email and take a peek at what’s inside.

Use this strategy when: You can genuinely point to a deadline by which the reader will need to act. It’s important that the reader feel these deadlines are legitimate.

10. Make your readers curious

Another classic persuasive strategy that applies to email subject lines is as simple as it is difficult to pull off: make your readers curious. Typically, you engender curiosity by leaving information out of the equation, but that can be a dangerous play when it comes to email subject lines.

Leave out too much information, and your readers won’t know what to make of the subject line. Put too much information in and your ploy for curiosity simply won’t work. The trick is to find the right balance–and that will often mean ensuring the subject line revolves around a topic the readers already care about.

Some examples of the curiosity strategy include:

  • Don’t open this email! (Manicube).
  • The best times to post on Instagram in 2019 (Later).
  • You’ll be checking out this new stuff All Night Long (All Night) (Thinkgeek).

You can see how sometimes this subject line almost employs a kind of reverse psychology. In other cases, they just hint at information that the reader would likely want to know.

Use this strategy when: You know that your users will appreciate a little bit of playfulness, or when you have some interesting information that you know your users will appreciate.

11. Ask your subscribers a question

When you use the word “you” in an email subject line together with a question mark, it’s human nature to be curious and want to do something about it. For example, consider these subject lines:

  • Jane, is this the product you’ve been waiting for?
  • Are you still deciding?
  • Do you need some style inspo? Check this out…
  • You don’t want FOMO do you?

Each of the about subject lines poses a question, asking the user to question themselves. This type of subject line is incredibly effective because it plays on a subscriber’s curiosity.

Obviously, if all your subject lines include “you” with a question, it’s not going to work — your subscribers will quickly cotton on to what you’re doing! But if you use this strategy sparingly, it’s a powerful way to boost your open rate.

Use this strategy when: … All else fails and you can’t come up with any other ideas for a subject line. This strategy is foolproof and one you should use sparingly.

Finding the right email subject line style for your newsletter

While there’s no single strategy that will get you a 100% open rate for your emails, employing the right combination of strategies will certainly help you increase your open rates for your audience.

Finally, I want to leave you with a couple of useful tools:

If you’re completely stuck for ideas, check out Kopywriting Kourse’s Subject Line Generator Formula. This awesome tool lets you input a copy and then spits out a huge list of email subject lines.

CoSchedule’s Headline Analyzer is another useful tool if you want to see how compelling your subject lines are. While it’s been designed for article headlines, it can help you write more powerful subject lines that captivate your audience.

What kinds of email subject line styles have worked best for your email newsletters? Let us know in the comments below!