The "King of Copy" is Giving Away Tips for Becoming a Top Paid Copywriter Right Now

Enter your email below to open Jeremy's daily email tips and a FREE audio training straight out of his exclusive paid membership – Copy Kings


The "King of Copy" is Giving Away Tips for Becoming a Top Paid Copywriter Right Now

Enter your email below to open Jeremy's daily email tips and a FREE audio training straight out of his exclusive paid membership – Copy Kings

How to Write Email Subjects Lines That Get Opened (Ultimate Guide for Copywriters)




You've written the perfect email, filled with value, insight and a persuasive CTA. But… there’s one tiny problem.

Nobody opened it.


Because your subject line didn't grab their attention.

Email subject lines are your first and often only chance to make a great impression and get your email opened.

In this ultimate guide, we'll dive into what an email subject line is, the best practices to follow, and explore ten of the most effective types of email subject lines that force people to open, read and click on your emails.


What is an Email Subject Line?

An email subject line is the brief text you see in your inbox before opening an email.

It’s like the headline of an article or the title of a book – its primary purpose is to get readers to start reading the email. This short snippet of text is crucial because it determines whether your email gets opened or sent straight to the trash. Think of it as the gatekeeper to your content.

You’ll find the email subject line at the very top of your email, right after the sender’s name. It’s usually just a few words long, making every character count. Given that many people check their emails on mobile devices, where only a limited number of characters are visible, crafting a compelling subject line is more important than ever.

The ONLY goal of your email subject line is to grab your subscribers’ attention and get them to open your email.


How Long Should an Email Subject Line Be?


In the world of email marketing, length does matter.

The ideal length for an email subject line is between 6-10 words or approximately 50 characters.

This sweet spot ensures that your subject line is fully visible in most email clients, including those on mobile devices where screen space is limited.

Here's why this matters:

Email platforms often trim subject lines that are too long, especially on smartphones. When your subject line gets cut off, the essential part of your message might not be seen, leading to lower open rates.

Imagine you've written a kickass subject line, but the most critical words are missing because they fall beyond the visible character limit. It’s like writing a headline only to have it partially obscured by a fold in the newspaper – frustrating and ineffective.

To make the most impact, keep your email subject lines concise and to the point. Prioritize the most important words at the beginning, where they are more likely to be seen.

This strategy not only makes your subject lines more effective but also respects your reader's time by quickly conveying the email's value.

The 10 Best Email Subject Lines to Boost Your Open Rates

1. Curiosity


Gary Halbert, one of the greatest direct response copywriters, often emphasized that curiosity is the single greatest motivator for why people purchase products.

When you spark curiosity in your readers, you tap into a powerful psychological trigger that compels them to find out more.

Curiosity-driven subject lines work because they create an irresistible urge to satisfy the reader’s need to know what's inside the email.

Curiosity makes your audience think they're on the brink of discovering something valuable or surprising. This sense of mystery can dramatically increase your open rates as readers click to uncover the full story or benefit.

Email subject line examples:

  • "We’ve been waiting for MONTHS to announce this…" - Carb Manager
  • "Don’t Open ‘Til After Dessert" - Rifle Paper Co.
  • "This is what your neighbor is doing this weekend" - Swiggy

By leveraging curiosity, these email subject lines encourage readers to open the email to quench their thirst for information, leading to higher engagement and better results.


2. Question


When posed with a question, especially one that resonates with their interests or problems, readers are more likely to open the email to satisfy their curiosity.

Questions provoke thought and create a direct interaction between your and your audience, making the email feel more personal and engaging.

Email subject line examples:

  • "Do you know these 10 email marketing tips?" - Mailchimp
  • "What's the secret to a perfect night's sleep?" - Casper​

Directly engaging readers with a question makes your readers feel compelled to open your email and discover the answer.


3. Emotional


Emotions drive action.

And when you can tap into relevant emotions that your audience are currently experiencing when they stumble upon your email, they will open it faster than a lightning bolt.

By appealing to your reader’s emotions, you can effectively grab their attention and create a fierce urge to read on.

Email subject line examples:

  • "We miss you! Come back and save 20% today" - Sephora
  • "You're not alone. We're here for you" - Calm
  • "Your exclusive invitation inside…" - The New Yorker​

These subject lines evoke emotions that prompt readers to open the email, whether it's the feeling of being missed, supported, or part of an exclusive group.


4. Benefit Driven

Benefit-driven subject lines highlight the advantages or positive outcomes your reader will gain by opening your email.

This type of subject line directly addresses your reader's needs or desires, making it clear that your email contains something valuable for them. By focusing on the benefits, you can effectively capture attention and entice readers to learn more.

When you promise a benefit upfront, it aligns with the reader’s interests and motivations, increasing the likelihood that they will open the email to reap the rewards.

Email subject line examples:

  • "Boost Your Productivity with These 5 Tips" - Evernote
  • "Save Money and Time with Our New Service" - Amazon
  • "Unlock Your Free E-book Today!" - Audible​

Benefit driven subject lines clearly communicate the benefits the reader will receive, encouraging them to open the email and take advantage of the offered value.


5. Numbers

Humans love lists.

We use them daily for taking notes, shopping, planning tasks, and more.

Lists provide a sense of order and predictability, making information easier to process. This is why numbered lists in email subject lines are so effective—they promise structured and scannable, digestible content.

Email subject line examples:

  • "7 Tips to Improve Your Morning Routine" - The New York Times
  • "5 Secrets to Boost Your SEO" - Moz
  • "10 Ways to Save More Money This Year" - NerdWallet​

By appealing to the reader's love of lists and structured information, these subject lines encourage email opens for quick, actionable insights.


6. Secrets


Who doesn't love discovering a hidden gem?

"Secrets of" subject lines play on the allure of insider information, making the reader feel like they’re about to unlock exclusive, valuable content.

It taps into the reader’s desire to gain an edge by knowing something that others might not.

This type of subject line suggests that the content will provide unique insights or tips that aren’t widely known, making it hard to resist opening the email.

Email subject line examples:

  • "Secrets of the Best-Performing Websites" - HubSpot
  • "Unlock the Secrets of Successful Blogging" - ProBlogger
  • "The Secrets of Perfect Coffee at Home" - Blue Bottle Coffee​

These subject lines promise exclusive knowledge, enticing readers with the prospect of learning something new and valuable that can give them an advantage.


7. Contrast

Subject lines that use contrast create a compelling tension that draws the reader in.

By juxtaposing two opposing ideas, you can create a powerful hook that piques curiosity and encourages email opens. Contrast can highlight a problem and solution, before and after, or any other pair of opposing concepts that naturally draw attention.

This technique works because it makes readers curious about how the two contrasting elements are related, prompting them to open the email to find out more.

Email subject line examples:

  • "From Zero to Hero: Transform Your Writing Skills" - Grammarly
  • "Why Cheap Can Be Expensive" - REI
  • "How to Be Both Productive and Relaxed" - Mindful Magazine​

Highlighting intriguing contrasts piques curiosity and drives readers to open the email to explore the surprising relationship between the opposing ideas.


8. Bizarre

wierd masks

Bizarre subject lines catch the reader’s eye with something unexpected or unusual.

They break the monotony of a typical inbox by presenting something that stands out due to its oddity or surprise factor. This can be incredibly effective in grabbing attention and prompting opens simply because the subject line is so intriguing or strange.

The element of surprise in bizarre subject lines disrupts the reader's routine, making them more likely to click out of curiosity.

Email subject line examples:

  • "Just wait till you see these oranges" - Nureply
  • "This email is not for you" - Urban Outfitters
  • "Why are we giving away free avocados?" - Chipotle​

These subject lines use odd or unexpected elements to create intrigue, compelling readers to open the email to see what it's all about.


9. Mistakes to Avoid

People are naturally curious about avoiding pitfalls, especially if it helps them improve. Email subject lines that focus on common mistakes and how to avoid them attract attention by promising to save readers from making errors. This taps into a desire for self-improvement and learning from others' experiences.

By highlighting mistakes, you can position your email as a valuable resource that offers guidance and helps the reader avoid potential problems.

Email subject line examples:

  • "Are You Making These SEO Mistakes?" - Neil Patel
  • "5 Common Blogging Errors and How to Avoid Them" - HubSpot
  • "Top Social Media Mistakes to Avoid" - Sprout Social​

Playing on the fear of making mistakes, these subject lines motivate readers to open the email and learn how to avoid common pitfalls.


10. Current Events

What's the most-watched TV show? The news. Why? Because it gives you fresh, relevant updates every day. You can tap into this same curiosity by teasing current events in your email subject lines. By aligning your content with something timely, you can make your emails feel immediate and important.

This approach works because people want to stay informed and not miss out on what's happening right now. It creates a sense of urgency and relevance that’s hard to ignore.

Email subject line examples:

  • "How the Latest Google Update Impacts You" - Moz
  • "The Impact of COVID-19 on Freelancing" - Upwork
  • "What the New Tax Laws Mean for You" - TurboTax​

These subject lines leverage current events to draw readers in, making them eager to open the email and stay up-to-date with the latest information.



Use these 10 tips to skyrocket your email open rates.

And, if you want daily copywriting tips to skyrocket your income this year, enter your email below:


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The "King of Copy" is Giving Away Tips for Becoming a Top Paid Copywriter Right Now

Enter your email below to open Jeremy's daily email tips and a FREE audio training straight out of his exclusive paid membership – Copy Kings


The "King of Copy" is Giving Away Tips for Becoming a Top Paid Copywriter Right Now

Enter your email below to open Jeremy's daily email tips and a FREE audio training straight out of his exclusive paid membership – Copy Kings