10 Email Subject Line Best Practices to Skyrocket Opens

Picture of Julia McCoy

Julia McCoy

Creator and Co-founder

email subject line best practices

Picture this: You’ve just crafted an email that’s pure gold, packed with content ready to dazzle your subscribers. But then, it sits unopened, lost in someone’s inbox —  or worse, the spam folder.

The culprit? A lackluster subject line.

Email subject line best practices are your secret weapon for slicing through the clutter. With a sprinkle of personalization and a dash of intrigue, you can boost those open rates sky-high.

It’s not rocket science; certain tweaks make people more likely to click open.

This guide will help you master crafting punchy subject lines and optimize them for various devices and email clients — essential moves in today’s mobile-first world. Plus, we’ll dive into real success stories where top-notch subjects made emails irresistible.

Table Of Contents:

10 Email Subject Line Best Practices

In today’s digital whirlwind, your email message competes with hundreds in an inbox, and you’ve got mere seconds to captivate interest before your masterpiece is relegated to the archives — or worse, the dreaded trash bin.

So how do we stop our emails from meeting such a grim fate?

Well, it starts with mastering the delicate craft of writing irresistible email subject lines — those few crucial words that can make or break your reader’s decision to click through.

Here are some of the best practices for writing email subject lines.

1. Personalize Your Subject Lines

Personalization is the key to capturing your subscribers’ attention in a crowded inbox. It’s not just about addressing them by their name; it involves understanding their needs, preferences, and behaviors to deliver relevant content that resonates with them.

Instead of sending emails from a generic brand email address, why not send messages from an individual in your company? This simple tactic adds a human touch and makes recipients feel like they’re receiving a personal email rather than promotional brand communication.

Beyond using real names for sender addresses, you can also personalize email subject lines based on what you know about each subscriber. For instance, if heavy snowfall is predicted in Toronto where some of your subscribers live, those individuals might receive an email with this subject line: “It’s snowy in Toronto – get 20% off leather jackets.”

This type of geo-targeted personalization shows that you understand and care about your audience’s specific circumstances or challenges. It helps make your emails more relevant and appealing amid the numerous other messages vying for their attention every day.

In essence, effective personalization is all about making sure each recipient feels valued as an individual rather than being seen as part of a mass marketing effort.

2. Keep It Brief Yet Impactful

In today’s fast-paced digital world, brevity is key — especially when it comes to email subject lines.

Nearly half of all individuals prefer viewing their emails on a mobile device, meaning that lengthy subject lines often get cut off in mobile view. This means that your message should be able to get across within those first few words.

A study conducted by Marketo found that four-worded subject lines received the highest average open rates at 18.26%. However, while open rates are important for gauging initial interest, click-to-open (CTO) rates provide deeper insights into user engagement levels as they measure both opening the mail and clicking on at least one link within – essentially capturing conversions.

  • The highest average CTO rate was observed with seven-worded subject lines (10.8%).
  • Nine-worded ones followed closely behind with an average CTO rate of 10.6%.
  • Six-worded subjects also fared well with a 10.1% CTO rate.

These statistics underscore the importance of keeping your email subject lines concise yet compelling enough to entice readers not just to open but to engage further with your content.

Source: Business 2 Community

3. Maximize Preview Text

Email subject lines are the first impression that you make on your audience, and as such, they should be impactful and concise. But there’s more to an effective email than just a catchy subject line — you also need to leverage the preview text or pre-header for maximum impact.

In an example from InVision, the subject line reads “Real World: Product Design” while the preview text provides additional information with “5 UX career trends for 2019. Plus, the true life of a lead product …”. The combination of these two elements creates intrigue and offers value right off the bat.

The key here is not to repeat what has already been said in your subject line but rather expand upon it or provide extra details in your pre-header section. This can include highlighting something introduced by the subject line or including a detail that isn’t evident from reading only this brief intro.

Tips for leveraging the preview text effectively:

  • Keep It Short: Aim for around 26 characters in your subject lines so they don’t get cut off on mobile devices.
  • Add Value: Utilize up to 68 spaces here for added context without being overly verbose.
  • Avoid Repetition: Don’t simply restate what’s already been mentioned in your headline – use this space strategically!

An effectively crafted email isn’t about cramming as much information into every nook and cranny possible; instead, it’s about using each element wisely — creating harmony between them while maximizing their combined potential impact on readers.

4. Draw Attention with the Right Emoji

Picking just the right emoji can be like choosing the perfect accessory — it should complement but not overwhelm your outfit — or in this case, your message.

A well-placed emoji grabs attention and conveys emotions faster than words ever could; think of them as shorthand for sentiment or humor. But there’s an art to effective use of emojis in email subject lines without stepping over into unprofessional territory.

Your audience is unique: what delights one person might confuse another. So knowing who’s on the other side of that email is crucial when incorporating emojis into subject lines. This understanding will help prevent false promises through misinterpretation.

Different devices also render emojis differently — which means what looks fine on a desktop computer could appear completely foreign on a mobile device.

Source: Finances Online

5. Use Power Words

To elevate your email subject lines from ordinary to captivating, consider the use of power words. These are potent terms that can trigger an emotional and psychological response in your readers, making them more likely to open your emails.

Power words spark curiosity, appeal to vanity, build trust, or evoke a sense of FOMO (fear of missing out).

Arouse Curiosity

We all have an inherent desire for knowledge and understanding. This is why phrases that leave us with unanswered questions or present something that contradicts our beliefs tend to pique our interest.

For instance: “Wonder How We Make Our T-shirt Unique?” or “7 Unexpected Tactics to Increase Your Sales.”

Appeal To Vanity

Vanity-appealing power words tap into the human need for admiration and recognition.

A great example would be: “A Dazzling Skin-Care Product That Will Make You Look Younger.”

The key here is not just using these powerful terms but combining them effectively without overdoing it.

Foster Trust

Incorporating trustworthy phrases into your subject line can help foster a sense of reliability among recipients.

For example: “Try These Bestselling Products” or “Get Lifetime Access to Our Membership Plan.”

Evoke Fear Of Missing Out (FOMO)

Lastly, you can evoke FOMO by telling recipients what they stand to lose if they don’t open your email.

For example: “5 Hacks You Must Know When Buying Jeans.”

When using power words in email subject lines, always keep balance in mind. Overuse can lead to desensitization, reducing the effectiveness of your power words. So use them sparingly and strategically for maximum impact.

6. Use Odd Numbers

The power of using numbers in your email subject lines cannot be overstated.

As Debra Jason, a renowned marketing expert once said: “Our brains are attracted to numbers because they automatically organize information into a logical order. A single, small odd-numbered digit, like seven, for example, is like candy for your organizational mind.”

This is particularly true when it comes to crafting compelling email subject lines.

A study conducted by Yesware, which analyzed 115 million email subject lines, found that including numbers increases open and reply rates significantly. Numbers provide clear and concise information, making them visually distinct from letters and thus more likely to catch the recipient’s attention in their inbox.

To illustrate this point further, let’s consider two similar messages:

  • Email Subject Line A: “How you can increase your profits”
  • Email Subject Line B: “7 proven strategies for increasing your profits by 30%”

Between these two options, Email Subject Line B works better as it sets expectations clearly while providing an enticing snapshot of what’s inside for the recipient.

Incorporating specific figures not only makes your emails appear more credible but also helps readers quickly grasp the value proposition being offered.

7. Get to the Offer Quickly

It’s crucial to make your value proposition clear right from the start. This principle applies not just to your overall brand messaging, but also when you’re crafting individual email campaigns.

Your email subject lines are essentially a promise of what recipients will find inside your email. It should be enticing enough for them to want to click and read more, yet honest enough so as not to mislead or disappoint them once they do open it.

Let readers know exactly what they stand gain by opening and reading through your message — whether that’s a special discount on their favorite product, an exclusive piece of information that can help grow their business, or even an inspiring success story related to how someone benefited from using your product/service.

If you’re offering a limited-time sale or discount on certain products/services, don’t hesitate to highlight this in your email subject line: “Enjoy 20% off all our premium services – Today Only!”

Sharing valuable insights is another way to pique interest: “Uncover Top Marketing Trends For 2024 Inside”.

You might also consider sharing customer testimonials or case studies like: “See How Our Software Helped XYZ Corp Increase Their Revenue By 30%”.

The key here lies in being transparent about what recipients are going to get after opening your email. Make sure your offer is compelling and irresistible, yet completely honest. Avoid making false promises just to earn an open – it could harm your brand’s reputation in the long run.

8. Make an Announcement

The power of announcements cannot be underestimated when it comes to email marketing. Announcing new product releases, updates, limited editions, or upcoming events in your organization not only keeps your audience informed but also generates a sense of excitement and anticipation.

A good email subject line can make all the difference here — it should convey that feeling of insider news or exclusivity. Remember, the goal is to entice recipients into opening the email and engaging with its content.

Let’s compare:

  • Email Subject Line A: “New Feature Update”
  • Email Subject Line B: “You’re Invited: Exclusive Sneak Peek at Our New Feature”

Subject Line B creates curiosity while offering value by making readers feel part of an exclusive group getting early access to information.

If you are announcing an event or webinar, for example, consider using urgency in your email subject lines.

For example: “Save Your Seat! Only 10 Spots Left for our Exclusive Webinar”

This encourages immediate action from your subscribers due to scarcity.

9. Avoid Shouting

Have you ever received an email with a subject line that seemed to be yelling at you?

Something like “OPEN NOW—YOU WILL BE SURPRISED!” can feel more like a command than an invitation, and it’s not the best way to engage your audience.

In fact, such aggressive tactics could get your emails flagged or marked as spam by many email service providers. It’s always better to approach your audience in a less confrontational manner when crafting email subject lines.

All caps should never be used in email subject lines. They give off the impression of shouting and can turn off potential readers. However, experimenting with different case styles – sentence case, title case, or lower case – may yield interesting results for engagement rates.

No matter which casing style you choose, avoid sounding overly promotional or desperate. Instead, focus on creating catchy email subject lines that spark curiosity and provide value.

10. Test Your Way to Success

If you want higher open rates, don’t guess what might work; test it. Optimizing subject lines through A/B testing can skyrocket your success story.

A/B testing lets you send email variants to see which subject line not only makes people click open but also keeps them engaged.

Create an A/B Test, then sit back and watch as data pours in showing which phrases or strategies lead to more emails opened.

The knowledge you gain from successful email split tests goes beyond boosting immediate open rates — it helps refine future campaigns too. Use findings from past tests when sending out new product releases or holiday specials like Black Friday promotions. If something worked before, there’s a good chance it’ll succeed again under similar circumstances.

Improve Open Rates With a Killer Subject Line

Remember, your subject line is your first (and often only) shot at capturing attention in an overflowing inbox.

Keep it concise yet compelling; personalize whenever possible to forge a connection with your reader; and don’t shy away from A/B testing different strategies to see what resonates best with your audience.

Crafting compelling subjects isn’t just an art; it’s backed by data-driven strategies that lead to real results.

By sparking curiosity and steering clear of spammy tactics, you’ll be well on your way to crafting subject lines that not only stand out but also encourage clicks.

You’ve got this! Now go out there and write those eye-catching titles that get people clicking faster than ever!

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