Best Email Marketing Subject Lines That Capture Attention

I’ve got a stat for you.

Eighty-nine percent of respondents in a recent report said they open brand emails every single time due to two powerful factors: relevance and a killer email marketing subject line.

Here’s another stat: Sixty-four percent of people decide to open or delete an email based on the subject line. Even more striking, 69 percent use the subject line as the main reason to mark emails as spam.

If your subject line doesn’t spark interest or create intrigue, your email won’t get opened. And your open rates? They’ll tell you exactly how well your campaigns are performing.

Want more clicks and conversions? Mastering the art of subject lines is key.

Key Takeaways

• Sixty-four percent of subscribers will open an email based on the subject line.
• Email subject lines are crucial for capturing attention and can significantly impact open rates, making them a vital component of successful email marketing campaigns. 
• Conciseness is key. Ideally keep your subject lines under 50 characters, to avoid being cut off on mobile devices and to ensure clarity and relevance for recipients. 
• Using common spam triggers such as excessive punctuation or phrases like “FREE!!!” can lead to lower deliverability and emails landing in junk folders. Clear and relevant subject lines are essential. 
• Personalizing subject lines can increase engagement and open rates. Techniques such as addressing the recipient by name or referencing their previous interactions can enhance open rates.

Table of Contents

• Key Takeaways     
• What Determines Email Open Rates
• Best Subject Lines for Email Marketing
• 1. Subjects that Generate Curiosity
• 2. Subjects that Communicate Urgency or Scarcity
• 3. Subjects that Include Free Offers
• 4. Subjects that are Personalized
• 5. Subject Lines that Highlight Recent News Topics
• 6. Subjects that Communicate Social Proof of Concept
• 7. Subjects With A Story Tease
• 8. Subjects with Retargeting Campaigns
• 9. Subject Lines that Include Announcements and Events
• 10. Subject Lines with Your Authority and Expertise
• Common Email Subject Line Mistakes
• FAQs
• Conclusion

What Determines Email Open Rates

Frequency, relevance, email marketing subject lines, and list quality impact email open rates, but there are other factors. I’m talking about things like:

• The time you send emails. Send your emails out at peak engagement times for better open rates. Brevo has some fresh research on this, so check it out. Your email provider should also have features to measure this.
• Personalizing subject lines can increase engagement and open rates. Techniques such as addressing the recipient by name or referencing their previous interactions can enhance effectiveness.
• Email types. GetResponse’s research shows RSS has the best open rate, followed by autoresponder newsletters. Triggered emails (automated emails based on shopper behavior) and newsletters come in third and fourth.
• Character length counts. GetResponse says subject lines with 70 characters max receive the most opens. 
• Individual words like “Invitation,” “news,” and “new” have higher opens. Words like “free,” “offer,” and “lifetime” get fewer opens.
• A unique selling proposition: What do you offer that other businesses don’t? For example, let’s compare two top ridesharing sites: Lyft and Uber. Which one inspires you to click?

Uber’s booking system is front and center, but you need to jump through a few more hoops to book with Lyft. Eliminating this friction allows customers to take action right away, making for a better user experience on Uber.

Best Subject Lines for Email Marketing

Different types of subject lines drive higher open rates. Some create urgency, others create intrigue, and some tap into emotions. Understanding these types helps you craft subject lines that grab attention and entice readers to open your emails. Let’s explore some of the best subject lines for email marketing.

1. Subjects that Generate Curiosity

It’s human nature to be curious, and you can use this to your advantage by crafting subject lines that pique interest. Don’t give away all the information—just offer a teaser.

For example, if your subject line says, “Women Are More Active on Social Media Than Men,” there’s no reason to click because the sender has already given the answer. Instead, tease what’s inside to boost open rates.

Here’s an example from Tripadvisor

Now that they’ve opened the email, you want to improve your click-through rates. How? By continuing to stimulate curiosity within the body of your message.

Let’s continue using the same example. Tripadvisor still doesn’t reveal the answer even after the reader opens the email, encouraging a click-through.

By stirring curiosity with the subject line, you:

• Increase your open rate
• Improve your click-through rate
• Drive more traffic to your website
• Potentially increase conversions

Starting from the hook in the subject line, you can keep readers engaged from the subject line to the email body to encourage clicks.

Effective subject lines keep your subscribers guessing and on their toes.

2. Subjects that Communicate Urgency or Scarcity

Emails with urgent subject lines tend to get opened more often because they leverage FOMO (fear of missing out). It works because our brains are wired to prioritize quick action when faced with the possibility of losing out, making urgency a powerful trigger for engagement. 

Think about it. Airlines and hotels do this all the time.

• “Only 4 seats left on this flight.”
• “3 rooms left for these dates.”

Adding a tight deadline makes this strategy even more effective. Look Fantastic used this technique by creating urgency in the subject line and a compelling call to action in the email body.

You can also create urgency with your word choice. Benchmark studies show that subject lines with words like “quick” or “today” have open rates of 36.18 percent and 45.6 percent, respectively.

Scarcity and urgency go hand in hand when it comes to email marketing methods.

Try it out with your next campaign.

3. Subjects that Include Free Offers

Want to make your customers happy? Send free offers and promotions to your email subscribers. Freebies also give your customers a reason to open and click through your messages, and they get you sales.

Studies show that giveaways have a conversion rate of around 34 percent.

Everyone loves a freebie, but the psychology behind it runs deeper than that. Subject lines that suggest a benefit activate what’s called the brain’s reward system.

Just a note: If you’re concerned about using “free” in a subject line in case it triggers spam filters, look at this graphic from Invescpro for some reassurance:

“Use ‘free’ strategically and pair it with value-driven wording, e.g., ‘Get your free productivity guide today!

Finally, here are a few tips for writing your “freebie” subject line:

• Make it time-limited like your other offers.
• Personalize where you can. Use first names and target freebies to where your subscriber is in the sales funnel.
• Be clear. “Free templates” or “free downloads” work better than non-specific headlines.
• Read this list of email subject lines that can trigger spam filters.

4. Subjects that are Personalized

Using personalization in your email subject lines creates trust and can help you establish a long-term relationship. But there are other reasons you’ll want to get personal, like increased conversions.

Further benefits of personalization include:

• Increased open rates and click throughs.
• Better engagement and response rates.
• Improved segmentation to better target customers.
• More conversions and sales.
• A personalized customer experience for improved customer loyalty and repeat customers.

Here’s an example of how personalization can impact your emails.

Ready to start writing subject lines? Here are some ideas:

• Use a recent purchase to follow up with your customers.
• Send your subscribers messages on their birthdays.
• Send emails based on their search history. “Looking for this season’s hottest sportswear? Here’s a special offer just for you!”
• Personalize it by budget, location, or family makeup. For example, “New parent? Must-have baby essentials at the best prices!”

5. Subject Lines that Highlight Recent News Topics

People want to receive breaking news because it creates a sense of urgency, and we all want to be in the know.

So give subscribers what they want by writing relevant content on hot topics. 

Let’s say you own a local coffee shop.

You could write around topics that matter the most to consumers, like:

• Sustainability and ethical sourcing.
• Economic and trade issues. For example, tariffs might make sourcing coffee more expensive.
• Innovations and trends.

You can also make your brand part of the conversation by sharing company updates. A coffee shop owner could get creative and write subjects such as:

• Meet Your Barista: Get to Know the Faces Behind Your Favorite Coffee.
• Sustainability Matters: How We Source Our Beans from Ethical Farms.
• From Bean to Cup: The Journey of Your Favorite Brew.
• Fall in Love with Our New Pumpkin Spice & Maple Lattes!

See? It’s easy when you know how and can do the same for any niche.

6. Subjects that Communicate Social Proof of Concept

Social proof is a psychological concept, and the idea behind it is simple: If others are doing something, it must be right.

Here’s an example from IL Makiage:

Celebrities can help you create social proof as well. If you see someone famous using your product or service, email your customers and include the celebrity’s name in the subject with a quick tease about what happened.

SAXX Underwear does this with pro basketball player Aaron Gordon.

This example is from their website, but they can send email subjects with a similar tone using phrasing from their site like:

• “If you’re not wearing SAXX, you’re not changing the game.”
• “It’s about changing the game. One day at a time.”
• “Shop Aaron Gordon’s game-changing picks.”
• “Game-changing underwear.”

It’s a simple enough tactic. But it makes your products so much more desirable. I mean, if a pro basketball star loves your product, it has to be good, right?

And if you don’t have the budget for a celeb, you can always use influencers, micro-influencers, or user-generated content.

7. Subjects With A Story Tease

Everyone loves a good story. And just like we talked about earlier, storytelling generates curiosity and enables a personal connection. 

Marketers and brands love storytelling, too. It’s a go-to marketing method because stories provoke emotions, which drives sales.

Obviously, you can’t tell an entire story with just a subject line, but you can use it to tease, intrigue, and introduce a story.

Not sure what story to tell?

Start with your story. Remember that coffee shop example further up? Let’s use that again. Our fictional coffee store could create subject lines such as:

• We Almost Gave Up… Until We Found This One Perfect Bean
• We Took a Risk – Now It’s Your Turn to Taste the Reward
• From struggle to success: How we grew a thriving coffee shop
• The Mistake That Led to Our Best-Selling Blend
• From a Tiny Café to a Global Favorite – Our Journey

We only gave the introduction to a blog post in the body of the email. You can do the same thing when telling a story, like this:

• First, capture the attention of your subscribers with a catchy subject line about your story.
• Next, only include the first few lines or paragraphs in the email.
• Make them visit your website or blog to finish reading.

Businesses use storytelling as a content marketing strategy and research shows 92 percent of consumers want brands to produce story-like ads. 

Incorporate a story into your next email subject line and see if it works well for you.

8. Subjects with Retargeting Campaigns

Ever wonder what happens to your customers? They place something in their basket, and that’s the last time you hear from them. It’s a huge problem for e-commerce stores, with  70 percent of shoppers abandoning their carts.

And there are plenty of reasons why:

But abandoned cart emails can turn things around. These emails:

• Create a fresh sense of urgency.
• Allow you to personalize content and offers.
• Offer irresistible discounts or special deals.

If your customers frequently abandon items in their shopping cart, take action.

• Send a follow-up email sequence. Consider including a short survey asking why they changed their mind.
• Retarget with ads on Facebook, Google, etc.
• Give them free shipping.
• Tell your customer exactly what you’re offering in the subject line.
• Consider offering a guest checkout.

Use subject lines like:

• “Last chance! Items in your cart are selling fast!” 
• A little something to help you check out: 10% off!”
• “Wait, did you mean to leave this behind?”
• “We saved your cart—just for you!”

Need some more inspiration? Then, learn from top brands.

Here’s how Cartridge Discount does it.

9. Subject Lines that Include Announcements and Events

If your company is attending an expo or launching a live event, send customers an email invite or free or discounted tickets. These emails work because they can make customers feel like they’re part of an exclusive group and create a sense of excitement.

Try an email subject line like…

“Here’s 2 FREE Tickets. You’re invited to join us.”

It will encourage the reader to click the email and take advantage of your offer.

You don’t need a physical event to do this, either. Invites to online promotional events can work just as well. Look at this example from TED.

The “Imagine being at TED2025” subject line certainly captures your interest, doesn’t it? Then once subscribers read the messaging and viewed the images, well, I’d guess plenty of them are ready to book their tickets.

10. Subject Lines with Your Authority and Expertise

Earlier, we discussed the benefits of creating social proof of concept with celebrities and large groups of people. This is what I do. My experience makes me an expert in the industry, so I share this knowledge with my subscribers. Here’s an example from my website.

Are you thinking what I’m thinking? The example above would make a great email marketing subject line, wouldn’t it?

You can do this with your authority in a specific industry as well.

If you’re not an expert, find someone who is. Consider citing a doctor or a lawyer to support your points. Alternatively, reach out on ProfNet for interviews or quotes, or find PR agencies with clients in your niche.

Press release sites are also a good source. You’ll often see professionals putting out stories and positioning themself as authority figures. They’ve usually got quotes you can run with, or you can contact them for a unique comment.

Common Email Subject Line Mistakes

Email subject lines are easy to get right. But they’re just as easy to get wrong, and there are some mistakes that email marketers make regularly:

Hannah McDonald, Content Production Lead at NP Digital, explains:

“One of the most common flaws in email subject lines is a lack of clarity or relevance. This leads recipients to ignore or delete the email. Another issue? Overusing spam triggers like ‘FREE!!!’ or too many exclamation points. These can send your emails straight to spam.

We also have to remember that subject lines that are too long get cut off on mobile devices. Keeping them concise (under 50 characters) while conveying value is key to boosting open rates.”

Want some examples of what to avoid? Let’s start with too spammy:

The subject line includes words and phrases commonly associated with spam, such as “ALERT,” “WE ARE NOT RESPONSIBLE,” and “HACKED.” Spam filters often flag these terms because they create a sense of fear, a tactic frequently used in phishing or scam emails. There are also too many spam words in the subject line.

Then, there’s too long:

The subject line is 90 characters long (including spaces). Best practices suggest keeping subject lines under 50 characters for optimal readability, especially on mobile devices, where longer ones are cut off.

Other common email subject line mistakes to avoid include:

• Lack of Clarity and Focus: The subject line above contains two separate ideas: “A guide to guarantees” and “How we grew a business by 49% by adding a guarantee.” This could overwhelm or confuse readers, as it lacks a clear focus.
• Lack of Mobile Optimization: Mobile devices have a subject line visibility of 78 characters max. This means the key message may not be fully visible to recipients.
• Not A/B testing: Test areas such as length, tone, personalization, and try posing questions in titles.

FAQs

What is a good email subject line?

Make sure your email subject link invokes curiosity, shows your authority, and promises something of interest to the user.

What are some ways to personalize your subject line?

In most email providers, you can use placeholders to dynamically insert user’s names, order information, and other relevant data to make the subject line more personalized Tailored subject lines feel more personal and increase the likelihood of the email being opened.

How does FOMO (fear of missing out) factor into subject lines?

FOMO (Fear of Missing Out) plays a big role in email subject lines by creating a sense of urgency and exclusivity. When you make readers feel like they could miss out on something valuable, they’re more likely to open the email.

Conclusion

Choosing the right subject line can help you meet your marketing goals and there are plenty of approaches you can take.

Great subject lines spark emotion, build curiosity, and tease value. Tell unforgettable stories and create a sense of urgency with your subject lines. That’s how you enhance open rates and click-throughs.

You can also use personalization to connect with your customers and gain their trust and loyalty. 
These are just some ways you can use email marketing subject lines to entice and captivate subscribers eager to learn more.