When it comes to a successful email marketing campaign, good subject lines can make all the difference. Subscribers will scan the subject lines of virtually every message you successfully get into their inbox, and many will make the decision to open those emails based on the subject line alone.

Think for a moment about how hard it is to stop reading a single line of text in the middle. Once you start, you just can’t stop. That’s the power your subject line has over potential readers. Subscribers are more likely to see and absorb that one line more than any other part of your message. That gives it the chance to entice users to read the first line of inside copy.

So, how do you make the most of subject lines and position your email to reach your goals? Here are 18 email subject line hacks you can put into action right away.

1. Lose title case

Title case is great for books, but it looks out of place for most subject lines. Most emails should be written to connect with people — and for everyone but the Queen of England, that means a more conversational tone. Losing title case makes your email seem as though it’s coming from a friend.

2. Keep it short – five words or less

How long should you make your email subject lines? Well, almost half of emails are opened on mobile, which means there’s limited space for characters. Try to pick short, punchy words and keep it down to about 50 characters and no more than five words. This way, users can see the whole message, and act on it faster.

3. Make subject and copy work together

Most email clients show a preview of the message text immediately under the subject line. This has the potential to be longer: about eight to 12 words. Your subject line is the “implied promise” of your email, so make sure inside copy picks up from there and clearly keeps that promise. Many make the mistake of having the preview text match the subject line, but we recommend differentiating the two.

4. Personalize your subject lines

Personalizing subject lines makes subscribers feel as though the email you’re sending was created with them, in particular, in mind. Campaign Monitor has found that emails with personalized subject lines are 26% more likely to be opened, so consider adding a first name or other personalized detail.

5. Convey a sense of urgency

You don’t want people to read your subject line, and then skip over it. To encourage subscribers to open your emails right away, consider using words like “urgent” and “breaking,” which are considered the most potent words that imply time sensitivity, followed by “important” and “alert.”

6. Use announcements and invitations

The words “announcement” and “you’re invited” both have a powerful impact on open rates. After all, who doesn’t want to get the latest update or be invited to an interesting event? You don’t need to bend the truth to send an “invitation,” either: Anything from a webinar to a subscriber list-only white paper could merit an “invitation.”

7. Get attention with “thank you”

“Thank you” is one of the most striking two-word combinations you can use in any email subject line. It not only resonates deeply with others in a world where connections count, but also implies a meaningful, even reciprocal relationship between your brand and email readers.

8. Test multiple topics

Most subject lines focus on a single topic, so users who aren’t interested will instantly move on. Using multiple ideas in a subject line can increase open rates. For example, a retailer who lists two or three of the user’s top purchase categories only needs to hit on one “winner” per message.

9. Convey a sense of action

Verbs are action words: The things a person, place, or thing can do. Not only do they make your subject lines sound more active, but they also imply a call to action — without that, most Web users simply won’t convert, even if the step you want them to take seems self-evident.

10. Use your “From” name to your advantage

Emails that come from a person’s name are more likely to be opened than those sent by the name of a company. This will make your email subject line much more likely to be read. Be sure your subscribers know your name though, or it could backfire.

11. Focus on the pain point

We’ve all heard that email subject lines should focus on a benefit, something your prospect wants. However, many marketers have had great success with the opposite: Focusing on the pain point in the email subject. If it’s a good match with your prospects’ needs, they may jump!

An example:

  • Benefit: 4 ways to boost your business with email marketing
  • Pain: 4 email marketing mistakes (and how they hurt your business)

12. Open with a number

You probably noticed that the example above doesn’t use a verb. It starts with a number and gets straight to the point. Numbers have a hypnotic power to them: After all, you clicked on 18 email subject line hacks even though you might not find yourself implementing all of them!

13. Surrender to emojis 💌

B2B enterprises in conservative industries may still want to avoid emojis, but it’s time for B2C companies to embrace the wave 🌊.. Used strategically to reinforce the message, emojis raised open rates in B2C promotional emails by as much as 15%. 👩‍💻

14. Address an audience directly

If your email subscriber list is segmented properly, this is an easy way to score some big wins. Signaling a specific audience directly is a perfect way to engage attention and spark the curiosity needed to click through to your email.

For example:

  • Savvy chefs save on groceries with this trick
  • What CIOs must know about 2018 security compliance

15. Use alliteration

Literary devices like alliteration have been used for centuries because they can make a message more memorable. A little alliteration can go a long way to break the monotony of a full email box. Still, it’s not necessary to use it on every word in a subject line.

For example:

  • 5 fast fixes for customer service frustration
  • 6 solutions that simplify IT security

16. Try rhyming

A rhyming subject line may be the most difficult to pull off. You have to make your meaning clear, keep the message short, and still achieve your desired rhyme scheme. Subject lines tend to sound catchiest when they end with a rhyme.

For example:

  • 4 travel must-haves to buy before you fly
  • These new decor styles bring smiles

17. Skip the “free” lunch

It’s easy to assume free is a word that will grab readers. But the word “free” underperforms when compared to its little brother “freebie” in many campaigns, and it can also trigger spam filters. Skip using the word free in favor of more descriptive language.

18. Can the spam

Another reason “free” can sabotage your email campaign is simple: It may lower the deliverability rates of your emails. Other spammy culprits include fake “Re:”, all caps, one-word subject lines, and aggressive punctuation (think multiple $, ?, or ! symbols.)

Wrap up

Done right, your email campaigns will provide a compelling, personalized experience that can move prospects down the road to becoming valued customers. Test out these hacks with email analytics to monitor your results — you may be surprised to see what will work for you.