20 Tips to Write Catchy Email Subject Lines That Get Opened in 2024 [+ Examples]

Are you struggling to get people to open your emails? With the average person receiving over 100 emails per day, it‘s harder than ever to stand out in a crowded inbox. But fear not! We‘ve compiled the ultimate guide to writing irresistible email subject lines that will skyrocket your open rates in 2024.

Email remains one of the most powerful tools in a marketer‘s arsenal, with a whopping ROI of $36 for every $1 spent. However, one in five emails never even get opened. If your brilliantly crafted email copy goes unread, that‘s a lot of missed opportunities to connect with your audience and drive results.

The key to getting more opens lies in the subject line – that short but mighty phrase that can make or break your entire email campaign. In fact, 64% of people decide whether to open an email based solely on the subject line. No pressure, right?

Fortunately, by implementing a few proven subject line strategies and staying on top of the latest trends, you can dramatically boost your open rates and email marketing success. Here are 20 tips to write catchy email subject lines that will get your emails opened and read in 2024.

1. Keep It Short and Sweet

With 46% of all email opens occurring on mobile devices, brevity is more important than ever. Most mobile screens only display 30-40 characters in portrait mode. To ensure your subject line packs a punch:

  • Aim for 50 characters or less
  • Put the most important words at the beginning
  • Limit yourself to 5-7 words

For example, instead of:

"Newsletter: Tips for organizing your closet, maximizing storage space, and decluttering your wardrobe"


"10 quick closet organization hacks"

The second option condenses the key information into an easy-to-read package.

2. Create a Sense of Urgency

One of the most effective ways to compel opens is to create a sense of urgency and FOMO (fear of missing out). Subject lines that communicate scarcity and a ticking clock tap into humans‘ loss aversion bias.

Some urgency-inducing power words and phrases:

  • Act now
  • Before it‘s gone
  • Last chance
  • Limited time
  • Only X days left
  • Almost sold out

For instance:

"⏰ Your 50% off code expires at midnight!"

Just be judicious in your use of urgency tactics. If every email shouts "last chance", the effect quickly wears off.

3. Ask an Intriguing Question

Questions are naturally engaging as they compel our brains to pause and reflect. Using a question in your subject line draws the reader in and gets them thinking. For maximum impact, ask a question you know is relevant to your audience and that piques their curiosity.

Some examples:

"Quiz: How secure is your password?"

"Are you making these common SEO mistakes?"

"What do the most productive people do before 7am?"

Just make sure your email content actually delivers an answer!

4. Use Numbers, Lists, and Specificity

Our brains are naturally drawn to digits, which is why using numbers in headlines is a time-tested tactic for grabbing attention. Numbers also help quantify your message and set expectations for what‘s inside the email.

Some ways to use numbers:

  • Steps in a process ("3 simple steps to…")
  • List of tips ("7 ways to…")
  • Percentage or dollar amount ("50% off all…")
  • Time or money saved ("Save 2 hours per day by…")

The more specific your numbers, the more credible and compelling. For instance, "254% more leads" is more impressive than "double your leads."

5. Get Personal

Personalized subject lines are 22% more likely to be opened. While addressing recipients by name is the most obvious way to personalize, there are other factors you can use, such as:

  • Location (city, state, country)
  • Birthday or anniversary
  • Last product purchased
  • Position or title
  • Interests or preferences

For example:

"Seattle, get your exclusive invite!"

"John, see what other managers are reading"

Even if you don‘t have tons of personal data, using the word "you" makes your subject line feel more personal and relevant.

6. Segment Your Lists

Personalization starts with segmentation. The more you can slice and dice your email list into distinct groups, the more targeted and relevant your subject lines can be.

Some ways to segment:

  • Demographics (age, gender, location)
  • Customer lifecycle stage (lead, customer, past customer)
  • Purchase history
  • Email engagement (active, inactive)
  • Interests or preferences

For example, a clothing retailer could send different subject lines to men vs. women, or to people who bought in the last 30 days vs. 6 months ago.

7. Avoid Spam Triggers

Certain words, phrases, and formatting tactics are known to trigger spam filters and send your message straight to the junk folder. While exact spam triggers evolve, here are some current no-no‘s:

  • ALL CAPS and excessive punctuation!!!
  • Words like "cash", "quote", "cheap", "free", "deal"
  • Overtly sales-y phrases ("buy now", "make money")
  • Strange spacing or unusual characters
  • Misleading claims ("you‘re a winner!")

Focus on delivering real value rather than resorting to gimmicky tactics. Quality over clickbait.

8. Optimize Your Preview Text

The preview text is that short snippet that appears below or beside the subject line in many email clients. It‘s valuable real estate – a second chance to convince recipients to open. Most email clients display 35-140 characters of preview text.

Tips for preview text:

  • Treat it as an extension of your subject line
  • Highlight a key benefit, offer, or CTA
  • Include a cliffhanger that creates intrigue
  • Make it different from your subject line
  • Check how it displays across devices/clients

Here‘s a great example from Grammarly:

Subject line: "🎉 You + Grammarly = ready for anything"
Preview text: "There‘s so much to say – craft the perfect message for any occasion."

9. Test, Test, Test

While these subject line best practices are a solid foundation, what works best for your particular audience will be unique. That‘s why A/B testing is essential for optimizing open rates over time.

Most email tools like HubSpot, Mailchimp, and Campaign Monitor make it easy to test two variations of a subject line on a portion of your list, then automatically send the winning version to the rest.

Elements to test:

  • Length
  • Tone/Style
  • Including numbers
  • Personalization
  • Emojis
  • Capitalization

Remember, even small tweaks can make a big difference. Keep testing, iterating, and honing in on the subject line formulas that resonate with your audience.

10. Use the "From" Name to Your Advantage

The "From" name is one of the first things people look at when deciding whether to open an email – often even before the subject line. After all, we‘re far more likely to open an email from a name we recognize and trust.

Tips for "From" name:

  • Use a real person‘s name, not a company name
  • Be consistent – use the same name for all emails
  • Include your company name for clarity
  • Avoid "no-reply" names

For instance, an email from "Jill at Acme Inc" will likely perform better than one from "Acme Inc" alone. A familiar name helps your email feel more personal and less like mass marketing.

11. Provoke Curiosity (Without Being Clickbait-y)

While you always want to steer clear of misleading clickbait, piquing curiosity in your subject line is fair game and can drive opens. The key is finding that sweet spot between being vague and giving away too much.

Some curiosity-inducing phrases:

  • "You won‘t believe…"
  • "Guess what…"
  • "We were surprised too…"
  • "This changes everything…"
  • "Sneak peek inside…"

Use curiosity sparingly and strategically. The goal is a quick dopamine hit that makes the reader feel they need to open to satisfy their curiosity, not confusion or annoyance.

12. Write for Your Audience

What works for one audience may fall flat for another. Are your subscribers information-driven or emotion-driven? Do they prefer a casual or formal tone? Witty or straightforward?

The more intimately you understand your audience, the more you can tailor your subject lines to their unique interests, pain points, and communication style. Immerse yourself in their world:

  • Interview customers
  • Follow industry blogs/publications
  • Read audience comments and reviews
  • Send surveys on content/offers they want

Then reflect their language back to them in your subject lines. For example, a B2B cybersecurity company may find its audience gravitates toward no-nonsense, jargon-heavy subject lines, while a DTC skincare brand‘s audience prefers cheeky, emoji-laden ones.

13. Make It Mobile-Friendly

With nearly half of emails now opened on mobile, subject lines must be not just short but mobile-optimized. Some mobile-savvy formatting tips:

  • Limit subject line to 30 characters
  • Use pre-header/preview text wisely
  • Frontload important words
  • Check display on various mobile clients
  • Keep emojis to 1-2 maximum

Avoid phrases that will get cut off on mobile screens, like dates, numbers, and names. The truncated subject line "50% off all…" is much more compelling than "Mark your calendar for our…".

14. Align Subject Line With Email Content

Your subject line sets expectations for what‘s inside your email. Make sure you deliver on those expectations, otherwise you risk eroding trust and damaging your sender reputation.

Align subject line and email body by:

  • Matching tone and messaging
  • Delivering on promises/offers
  • Making content relevant to subject
  • Having a clear, singular focus
  • Expanding on points teased in subject

If your subject line is "10 tips to improve SEO", make sure those 10 tips are in the email. If you mention a specific offer, it should be easy to find and redeem. Consistency builds trust.

15. Optimize for Deliverability

Even the world‘s best subject line is futile if your email never makes it to the inbox. Poor deliverability is a silent killer, with around 20% of all emails ending up in spam.

Some deliverability best practices:

  • Use double opt-in to build a quality list
  • Remove inactive subscribers regularly
  • Avoid spam trigger words/tactics
  • Authenticate emails (SPF, DKIM, DMARC)
  • Maintain a consistent sending schedule
  • Monitor metrics like bounces and unsubscribes

Tools like GlockApps and MxToolbox can help you test and monitor deliverability. The better your sender reputation, the more likely your subject lines actually get seen.

16. Consider Emojis (If Aligned With Brand)

Emojis are now ubiquitous across digital communication and can add visual flair to email subject lines. In fact, 56% of brands using emojis in their email subject lines had a higher open rate.

Benefits of emojis in subject lines:

  • Stand out in crowded inboxes
  • Convey tone/emotion quickly
  • Transcend language barriers
  • Add personality to your messaging

Some brands that use emojis well:

  • Postmates: "🎉 You‘ve earned a Labor Day treat"
  • Uncommon Goods: "🌞 Sunny days ahead – our new outdoor collection!"
  • Toms: "👀 Spot it. Shop it. Own it."

Just make sure emojis are on-brand and used judiciously. One or two relevant emojis is plenty. Also, check that emojis render correctly across email clients.

17. Use Strong Action Words

Starting your subject line with a punchy action word grabs attention and inspires recipients to, well, take action. Actionable language makes your request clear and taps into our natural tendency to want to complete things.

Some action-packed power verbs:

  • Discover
  • Unlock
  • Reveal
  • Grab
  • Earn
  • Get
  • Start
  • Take

For example: "Unlock your free trial now" or "Discover the secret to better sleep". These verbs jump off the screen and create momentum.

18. Implement AI and Automation

As AI technology becomes more accessible, marketers can now harness machine learning to optimize subject lines at scale.

Some AI subject line tools:

  • Phrasee: Trains on your brand voice to generate human-sounding subject lines
  • Touchstone: Predicts and ranks subject line performance
  • Persado: Uses emotional language analysis to craft high-converting subject lines

These tools can generate more subject line variations than humanly possible to test, then continuously learn and adapt based on results. Expect to see more brands leveraging AI subject line optimization in the coming years.

19. Instill FOMO

69% of millennials experience FOMO, making it a highly effective motivator to encourage email opens. Subject lines that tap into people‘s innate desire to be included and "in the know" can significantly boost engagement.

Some FOMO-inducing tactics:

  • Exclusivity ("For VIP members only")
  • Scarcity ("Only 10 spots left")
  • Secrecy ("Behind the scenes of…")
  • Timeliness ("Today only flash sale")
  • Belonging ("Join 20,000 others at…")

Stir up just enough FOMO to pique interest without alienating. Make people feel they‘re part of a special community.

20. Stay Ahead of Email Trends

Just like SEO, email best practices are always evolving. To craft cutting-edge subject lines that stand out, marketers need to keep their finger on the pulse of the latest email trends and technologies.

Some subject line factors to watch:

  • AI-powered copywriting and optimization
  • Hyper-personalization and behavioral triggers
  • Interactivity (polls, games, AR)
  • Voice search and audio content
  • Omnichannel integration

While the fundamentals of human psychology remain constant, the way we communicate and consume content changes. Those who adapt their subject lines to new realities will win the battle for the inbox.

Bringing It All Together

In the quest for the perfect subject line, remember: there‘s no magic formula. The "best" subject line depends on your unique audience, brand, and goals. Use the tactics above as a starting point, but always be testing, adapting, and honing in on what works for you.

Catchy email subject lines are both an art and a science. It takes a deep understanding of your audience, a touch of creative flair, and a commitment to continuous optimization.

But the payoff is worth it. By crafting subject lines that are succinct, relevant, and thumb-stopping, you can dramatically improve your open rates, engagement, and overall email marketing ROI. So go forth and write awesome email subject lines that get opened, clicked, and converted. 🚀