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How to write a compelling email subject line (with 100+ examples)

Your subject line is your first impression on users. Don't let it be your last. A great email is nothing if it never gets opened. Let me show you how to write a compelling email subject line, and I'll even toss in a few examples you can borrow from.

How to write a compelling email subject line (with 100+ examples)
Photo by Yogas Design / Unsplash

I was talking to a coworker of mine who is also responsible for sending a lot of emails to our customers. We happened to talk about how easy it is to fall into a rut without realizing when it comes to using strong subject lines. We run a lot of tests across our email marketing program, but when it counts, we tend to fall into reusing high-performing subject lines from the past instead of pushing to find new winners.

To begin pulling ourselves out of this rut, we reflected on our process for composing compelling subject lines and we came up with the following:

  1. Using psychological principles common throughout marketing
  2. Relying on the tips and tricks we’ve built up over the years
  3. Falling back on our past winners

Considering we’re trying to pull ourselves out of falling back on the third item in that list, let’s start this post at the top and take a look at how we can all write more engaging subject lines that drive subscribers to open and convert.

What is an email subject line?

A subject line is the text appearing in your recipient’s inbox previewing the contents of the rest of the message. A subject line declares the intent of the rest of your email.

What is email preview text?

Preview text, often referred to as pre-header text, is the line of text that appears alongside your subject line. Preview text is not as prominent in your recipient’s inbox as your subject line but still is viewable from the inbox without opening the message, and serves as a sneak peek into the rest of your message.

Why should you care about writing a great subject line?

Your subject lines make or break your email marketing campaigns. It’s at the very top of your email funnel. The performance of your campaign is defined by how well your subject line performs.  

Elements of a compelling email subject line

The best way to write a compelling email subject line is to leverage psychological principles and appeal to human tendencies.


I’m sure all of your emails are important. But on the days you really want your audience to respond to your message, playing up its urgency with words like “urgent” or “important” or even “action needed” really works. Building up the urgency of your message increases your open rate. However, expect decreasing returns over time. Abusing your use of urgency will burn your subscribers out sooner than other strategies. Don’t become the brand that cries wolf.

"This term itself can create chaos in one’s mind. Urgency terms can become a tool for conversions. Also, this word will provide you with a sense of exigency or scarcity." – WP Swings


Human curiosity is a powerful thing. You may be able to write a subject line that conveys just the right message to get your subscribers to open, click, and ultimately convert. But sometimes, leaving a little mystery in your subject line may be just the hook you need to boost your open rate. Think about how we all pull down to refresh our various feeds throughout the day. We don’t know what will appear when we refresh, but we all want to see. Try hinting that there’s something inside for the subscriber when writing your next subject line. There is a cognitive reward for subscribers just in solving the mystery alone, that’s not to say this will work every time.

"People want to connect the dots, and when they can’t, their curiosity is powerful and motivating." – Social Media Examiner


Who doesn’t love a good bargain? Offers, incentives, discounts, and the like are all powerful tools for boosting your open rates. To get the most bang for your bargain offer, try to couple any incentives you offer to your subscribers with other principles outlined here. That 20% off discount might be appealing, and even rare for your brand, but your open rates are going to be much higher if it’s for a product or category that’s relevant to your subscribers. Keep in mind, you’re competing for attention in your subscribers’ inbox. Your offer needs to be more than an offer, it needs to stand out.

"In a world where consumers have more choices than ever, incentive marketing helps businesses grab the attention of customers with special deals or opportunities." – Power 2 Motivate


You’ve likely accumulated some bits and pieces of information about your audience over time. You likely know where in the world they’re located, the company they work for, and maybe their job title. You can use this all to your advantage in your subject line.

Consider using some of the more straightforward applications like pulling in the first name at the beginning or end of the subject line to make a direct appeal to your subscriber. You can also use those personalization tokens to segment your subject lines. Depending on your message, you can engage with your subscribers based on their location or job industry to make the subject line a little more personal to them. Make them feel important, make them feel special.

"Consumers don’t hate advertising; they hate bad advertising. They hate irrelevant brand messaging. Since personalized content is based on past behavior, it’s more likely the consumer will respond favorably to its message." – Instapage


The relevance of your subject line can be looked at in two different ways. The first, the relevance depending on your brand’s relationship with the subscriber: the actions they’ve taken on your site, the products they’ve purchased, the videos they’ve watched, etc. The second, the relevance of your message based on current events outside of that tight sphere: What stories are in the news? Is today a holiday? What’s trending on Twitter?

Your subject line should be relevant to your subscriber. Looking through that first lens, sending an abandoned cart email shortly after the subscriber adds products to their cart only to abandon can be a strong source of conversions. Especially if you tack on a discount to give a greater incentive to come back. Similarly, writing a subject line that ties to a story happening outside of your brand that you’re sure they will recognize is another powerful way to increase your open rate.


Depending on your brand and the relationship you have with your subscribers, your authority to speak to certain topics varies. If your company sells shoes and only shoes, you’re probably not going to be able to take advantage of national donut day to justify an email blast that day. When crafting the perfect subject line, put yourself in the shoes of your subscriber and ask yourself “Why are you telling me this?” Hold on to the topics you hold credibility over, and pass up the holidays or current events that might be too big of a stretch for your brand.


In journalism, one of the criteria for determining the newsworthiness of a story is its novelty. Stories that are bizarre, unexpected, and sensational can be considered newsworthy even if they fail to meet other criteria also not too unlike the concepts I’m explaining here (relevance, incentive, recognition). A dog biting a man isn’t necessarily a novel story, but a man biting a dog certainly has the potential to be.

What does this have to do with writing subject lines? Hit your subscribers with the unexpected. Show them the unusual products in your store, the unexpected promo code term, or even the discount for the holiday they never knew existed. Play up with puns or emojis to make it friendly and more welcoming if it truly is a bizarre play you’re making.

"Novelty is a source of attention that, in its pure form, is more associated with negative rather than positive initial responses. This is often surprising to marketers, who often assume that humans naturally like novelty." – Better Marketing

Tips for writing a great email subject line

With those principles in mind, let’s take this one level deeper and talk through some tips for applying that advice when writing your subject lines.

Six words or less

In six words or less, you can tell a very compelling story. Inspired by Ernest Hemingway’s famous six-word story, “For sale, Baby shoes, Never worn,” this format can be a powerful structure in email marketing. Limit yourself to six words or less and you’ll produce a subject line that not only packs a punch but can also be read in less time than it takes to mark your email as read.

Familiar from name

I beg of you to not send your email from “no-reply” no matter how badly you don’t want your subscribers to reply to your message. No-reply emails convey a specific unfriendliness that turns your subscribers off regardless of how compelling your email subject line is. Depending on your brand, company, and email program, you’ll have different variables to work with when determining your from name.

My suggestion to you is to try to use a real person’s name when possible. Ideally, a name the recipient will recognize like an account owner or customer success manager assigned to you. Lastly, make sure the from name matches the tone of your subject line. If you use emojis in your subject line, make sure the person assigned to the from name or your brand matches that same tone. Your from name should ultimately add credibility to your subject line.

Personalize with contact properties

You know a lot about your subscribers, use that to your advantage. The easiest and most popular way to personalize your subject lines with contact properties is by using the subscriber’s first name - addressing them by name in your subject line. Don’t stop there, you can pull in company names, purchased product names, locations, etc. to deliver a more relevant message to your subscribers.

Segment your lists

There is rarely a need to blast your full database. Not all subscribers are created equal, try segmenting your list based on user interests, industries, locations, time zones, etc. to deliver a more personalized subject line to their inbox.

A/B test

Unsure of which subject line to use? A/B test! Always be sure to isolate your tests to just a single value if your email marketing tool is unable to run complex multivariate tests. What do I mean by this? If you’re testing subject lines, make sure the preview text, email content, from names, and CTA button text are all the same. If you don’t, your test data will get messy as it will be hard to determine why one email outperformed the other, especially if you measure down-funnel metrics for success like purchase events or other conversions.

Don’t lie

We love a bargain, we hate bait and switch. You can very easily boost your open rates by sending out an extremely enticing subject line like offering 90% off your inventory. If the user opens your email only to see an April Fools’ Day message, you can rightfully expect your click-to-open-rate to tank, limiting the success of your lie.

Hint at what’s inside

We have all been trained to feel a sense of reward when we refresh our Facebook or Twitter feed. The jolt of happiness that comes from pulling down on our screen only to see a new unexpected message appear can be likened to why slot machines are so addictive. Stakes are a little lower here, but your subject line can still be a rewarding gamble for your subscriber if they’re compelled to solve the mystery of what’s inside this email you sent them.

Send it at the right time

As email marketers, we all love to hit send only to spend the next hour or so refreshing the results page to see how your email performs. That performance is largely dependent on the relevance of your message to your audience. While we often liken relevance to the content of the email, this also applies to the timing of your email. If your subscribers are scattered across a handful of timezones, you likely should not blast them all at the same time.

Similarly, you should send messages to your subscribers when the time is right in their purchase journey. Your newer subscribers likely need some more educational-type messaging before they’re ready to make a purchase. Your past customers likely won’t need to make a second purchase hours after completing a transaction on your site.

Be concise

Your space is limited when writing subject lines. Earlier in this post, I recommended sticking to six words or less. In addition to making your subject line short in length, make sure your message is concise in its contents. Avoid introducing too many ideas in this limited space, and instead, focus on making sure your message is clear and concise.

Stand out

I love the Inbox Zero method for my personal inbox. I cringe when I see screenshots of peoples’ home screens showing the tens of thousands of unread messages. In all forms of inbox management, your subject line is competing for attention. If your subscribers make sure their inbox stays nice and tidy, you only have a few seconds to convince them to open before your message is deleted or sorted into a folder. If your subscribers rarely open their emails, you need to make sure your subject line doesn’t blend in with the crowd.

Use emojis

Emojis can be polarizing. I’ve conducted a lot of A/B tests for a B2B company whose CMO wanted to incorporate more emojis only to learn they hurt our open rates. But that’s not the case for everyone, emojis can deliver more emotion than text and the color can help your subject line stand out in your subscribers’ inbox. Just be careful to not abuse your emoji privileges. Sending to your iOS mail app subscribers a subject line that starts with the blue dot emoji to make the message appear unread regardless of whether it has been opened or not should be illegal.

Don’t mix punctuation

You only have so much space to work within the subject. Mixing punctuation can create confusion, especially if your reader is only glancing at their inbox. Additionally, if you ask a question, rely on the contents of your email to give the answer. Do not give it away in the subject line with an exclamation.

Support with compelling preview text

Let your preview text be the leaping teammate in the alley-oop, making your subject line a slam dunk. You should never pose a question in the subject line with the answer in the preview text. Instead, build on the emotion evoked in the subject line, amplify it so the user opens the email.

100+ examples of great email subject lines

  1. {First Name}, your prescription is expiring
  2. Important Weather Advisory
  3. This one is on us!
  4. Coffee break?
  5. As you wish...
  6. Not cool, {First Name}
  7. Your coworker at {Company name} just signed up!
  8. Invitation for {First Name}
  9. We have a gift for you
  10. 13 lessons we learned from {Source}
  11. The best {topic} for this Spring
  12. See how you stack up to the competition
  13. Here’s why we’re cutting prices
  14. How we tripled our growth rate
  15. Avoid these common SEO mistakes
  16. We’re here to fix your {topc} problem
  17. Flash sale ends today
  18. The death of SMS
  19. Imagine {company name} without your {topic} problem
  20. The truth about {company name}
  21. {First Name}, we can help
  22. Don’t open this email
  23. Not cool, {First Name}
  24. Tonight only
  25. We need to talk…
  26. Need any help?
  27. You’re invited too
  28. Quick question
  29. Looking for your help
  30. Do you mind?
  31. Here’s why you’re falling behind
  32. Oh boy, do we have a story for you
  33. The customer is not always right
  34. Are you alright?
  35. You don’t want to miss this
  36. Are you missing the mark?
  37. They said it was impossible
  38. It’s time to come clean
  39. Keep it up, {First Name}
  40. You’re not alone
  41. Can you believe it?
  42. You’re running out of time
  43. Don’t let us down
  44. {Referral Name} just invited you to join!
  45. Next steps…
  46. One last chance
  47. Write a review, get a discount
  48. Tell us more about you
  49. Have you seen this?
  50. You’re in the top 5%
  51. {First Name}, where did we go wrong?
  52. Are you ready for it?
  53. Question for you
  54. Can you help me out?
  55. Happy birthday
  56. Falling short of hitting your goals?
  57. You’re missing out
  58. Free workshop
  59. Special thanks to {First Name}
  60. We appreciate your support!
  61. How was your service with us today?
  62. Share your experience with us!
  63. Check this out, {First Name}
  64. Looking forward to learning more about you
  65. Can you point me in the right direction?
  66. Question about {First Name}
  67. You’ve made this mistake before
  68. Resources for {First Name}
  69. How confident are you in {topic}?
  70. Have you heard about this?
  71. Where is the love?
  72. Welcoming you with a sweet treat
  73. You left this behind
  74. Is this yours?
  75. You just scored 15% off (but only for today)
  76. You’ll thank yourself later
  77. Thank you note for {First Name}
  78. Goodbyes are hard…
  79. Ready to win?
  80. There’s still time, {First Name}
  81. Which do you prefer?
  82. Take care now, {First Name}
  83. I wouldn’t be surprised if we never saw {topic} again
  84. Cheers to you
  85. Meet your match
  86. There’s a party in this email, you’re invited
  87. Welcome, we’ve been expecting you
  88. Next steps for {First Name}
  89. Things are going to change here
  90. Why {Company Name} is failing
  91. Partner?
  92. Where does {Company Name} rank?
  93. Quick favor?
  94. Are we okay, {First Name}?
  95. You’re not ready for this
  96. Have we met before?
  97. This isn’t going to work
  98. Can I help you?
  99. Where are you?
  100. Where did you go?
  101. We missed you, how’s tomorrow?


Your email subject line is at the very top of your funnel. If you want to drive conversions, you need to compel your subscribers to open. A good subject line evokes emotion in the reader and compels them to open.

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