34 Killer Cold Email Subject Line Examples for Guaranteed Response

Whether you’re in sales, recruitment, marketing, or any other field, there are times when you need to reach out to strangers to help you achieve your goals.

To do that, you must know how to craft and send cold emails.

With over 4 billion people using email, it’s one of the most effective ways to reach out and connect with your prospects.

But it’s also challenging. The average person receives up to 120 emails per day and 99% of cold emails will be deleted immediately.

So, how can you make sure yours is part of the 1% that makes it through?

Answer: By writing a compelling cold email subject line.

A good subject line is critical to email marketing, as 47% of people choose whether to open emails based on the subject line. And 67% will use subject lines to decide whether to mark an email as spam.

And subject lines are even more important for cold email campaigns. That’s because the recipient doesn’t know who you are and has no reason to open your email.

Your subject line needs to build both trust and curiosity at first glance.

This article lists 34 cold email subject line examples to help ensure your cold emails get read.


What Is a Cold Email?

Let’s quickly define cold email campaigns before diving into our cold email subject line examples. Simply put, a cold email is one you send to a person you don’t know.

The purpose is to get the recipient to help you achieve a particular goal. This goal can be anything from making a sale or building backlinks to your website to recruitment and everything in between.

The key to a great cold email is that it must propose a transaction beneficial to both the sender and receiver.

Cold emails aren’t just reserved for sales. You can use them for many different purposes, as their primary function is to connect you to people you can partner with for any kind of venture.

What makes a great cold email?

One of the main reasons cold emailing has earned a bad rep is that many people don’t know how to write a cold email.

Most cold emails suck.

And because they are poorly written, most get sent to the trash folder unopened.

So, what makes that a great cold email gets opened and read?

Here are a few elements you need to get right for your cold email to work:

A killer cold email subject line

Your cold email subject line must be less than 60 characters in length. If you go longer than that, it gets truncated and loses its meaning and impact.

Personalized content

Your email copy must be personalized to be on trend. To do this, you must research your target audience well.

A good pitch

The way you ask for what you want is crucial. You must do it in a way that isn’t too pushy or salesy.

An incentive

What will your recipient get from transacting with you? Offer them an incentive that they find both relevant and appealing.

A compelling call to action (CTA)

Your call to action is what seals the deal. It’s the statement you use to move the reader toward taking the next step.

Getting your cold email right is essential to ensure good open and conversion rates. So take your time to know your prospects and craft an email they’ll love.

34 Best Cold Email Subject Line Examples

Ready to get your next cold email campaign underway?

For you to enjoy good email open rates, you must nail the subject line. Your cold email subject line is the first thing your recipients see when your email lands in their inbox. Its main function is to encourage your recipients to open your email.


💡 Beware the dreaded spam filter
A good cold email subject line is not only critical to ensure your email gets opened, but it also helps avoid your email getting flagged as spam.Email servers use signals to decide whether your message is spam. Some of the signals it uses for this include how many people:

  • Delete your message
  • Move your message to junk
  • Ignore your message

If any of these happen too much, your message might get flagged as spam and go straight to people’s junk folders.Remember that stat I mentioned earlier—that 67% of people decide to flag emails as junk based on the subject line?

If your subject lines are substandard, you could be on a highway to people’s junk boxes.

In essence, your cold email subject line determines whether your email will be opened or not. Your email campaigns’ success depends on it. And that’s why you must take your time to develop the best ones. A few best practices to help you craft good subject lines include:

To help you craft your own catchy subject lines, let’s look at some of the best cold email subject line examples we’ve seen. We’ll also look at what makes them so successful. This will help you gain insight into best practices to implement in your cold emails.

Short subject lines

Short subject lines are best for grabbing attention. That’s because they are punchy and get straight to the point. They can also be easily digested at a glance, which allows your recipients to quickly decide whether or not they want to open your email.

Here’s a good example of one I received the other day. Despite being short, the value the email offers is clear:

And if you craft your short cold email subject line well, you greatly increase the chance that your prospects will open it. Here are some examples to inspire you:

  • I can help you [goal/aspiration].
  • This sales strategy rocks!

Question-based subject lines

Another type of cold email subject line you can use in your campaigns is the question-based subject line. For this type of subject line to work, your questions must:

  • Be relevant
  • Be provocative
  • Arouse curiosity

With these three ingredients in place, your subject line will encourage readers to open the email to learn more. Here are a couple of examples of question-based subject lines:

  • Got a moment to talk about your career as a [career type]?
  • Tired of not meeting your goals?

Question-based emails work well because the question implies the email contains a solution to a pain point. Of course, this will help drive your open rates up.

In the example below from lettings software Goodlord, the question challenges you and suggests limitless potential:

Personalized subject lines

People feel more comfortable when they interact with things they’re familiar with. It’s basic human nature.

And that’s the reason personalized cold email subject lines work so well.

The main way to personalize your subject line is by using the recipient’s name. However, with a bit of creativity, you can take personalization to the next level. All you have to do is infuse a familiar element or two in your subject line. This will make your recipient feel there’s a connection between you and them. As a result, they’ll feel safer opening your email.

And there’s data to back this up. Research shows that personalized email subject lines can result in 50% higher open rates. Personalized subject lines are also beneficial as they help reduce spam complaints.

Need an example of a personalized cold email subject line?

Here are two to inspire you:

  • Remember me? We met at [event/place].
  • Hey [first name], interested in [offer/benefits of your offer].

The main aims of personalization are to grab your recipient’s attention and inspire trust. Doing so will ensure that your campaign succeeds, simply because more people will open your email.

Humorous subject lines

Humor is (almost) a universal language—everyone loves a good laugh. And that’s why humorous subject lines are a great way to warm up your prospects.

Granted, you must be careful with this type of subject line as people view and experience humor differently. That’s why you must make sure your humor is tasteful and witty.

Need some examples of tasteful humor used in cold email subject lines?

  • Wanna know what tearing my pants (on the subway) taught me about marketing?
  • The ’80s called, and they want their sales strategy back.


FOMO-fueled subject lines

It’s human nature not to want to miss out on anything. That’s why the fear of missing out (FOMO) can be an excellent cold email subject line ingredient. To pull this off, your subject line must:

  • Create a sense of urgency.
  • Leverage negative exclusivity.
  • Use language that triggers FOMO.

Here’s a good example of this from SEO training website, Authority Hacker:

Sometimes all people need to take a step is a small nudge. And FOMO is one of the best ways to give your prospects that gentle nudge. Here are a few more examples of FOMO in action:


  • Are you the only one who hasn’t heard?
  • Don’t be like Jake, who missed this [offer] last year.

Use FOMO to hook your prospect in and direct them to your offer. Try not to overuse FOMO in your cold email subject lines. If you use it in the initial email, don’t use it in the follow-up. Doing so will diminish the value of the offer, along with the urgency.

Rock-the-boat subject lines

While taking the safe route is usually better when you’re initiating contact with strangers, sometimes you must “rock the boat” to get them to pay attention. Rock-the-boat subject lines involve writing something controversial, opinionated, or shocking. While you run the risk of alienating your audience, if you can craft your subject well, you’ll:

  • Make your email stand out.
  • Arouse curiosity.
  • Spark conversation with your prospects.

Here’s another one from Authority Hacker. Seeing that they offer an SEO training course and have customers working in the sector, this will be a controversial statement:

With so many emails hitting your prospects’ inboxes, sometimes you must make a bold move and dare to be different. Rock the boat if need be. The worst that could happen is that they’ll ignore your email. However, if your cold email subject line succeeds to rock the boat in the right manner, you’ll enjoy good engagement rates.

So what do rock-the-boat email subject lines look like?

  • You’re wasting time and money on your design tools.
  • Do you really know where your marketing spend is effective?

This type of cold email subject line delivers a punch that will stop your prospects in their tracks. It must be so thought-provoking that it elicits a click.

Email Subject Lines for Sales Prospecting

Outbound sales prospecting is one of the main areas where cold emails are used. And because this is where most businesses generate a significant portion of their leads, the initial cold email must be crafted with care.

An element that must be treated with the utmost importance is, of course, the subject line.

Let’s look at a few cold email subject line examples you and your sales reps can use in your sales prospecting emails.

The value-focused subject line

The value-focused email subject line, as the name implies, is all about showing your recipient why they should open your email. It pitches the value they’ll get when they open your sales email. This is super important, as studies show that the average person sends and receives an average of 126 business emails per day.

With such a high volume of emails in their inbox, your recipients will only open emails that add value to them. That’s why value-focused emails are an excellent way to drive open and conversion rates.

Here’s one I recently received from SEO tool, Moz:

Let’s take a look at a few value-focused cold email subject line examples, shall we?

  • We helped Joe rank on page one of the SERPs. We can help you too.
  • Increase your remote team’s productivity with this fantastic tool.
  • [Product] can help your team save 12 hours a week.

If you can compress your email’s value into a catchy subject line, you’ll undoubtedly stand out in crowded inboxes.

The referral/name-dropping email subject line

If your product or service is good enough, chances are that happy customers, or other people in your network, will happily direct you to potential customers. To prepare for this opportunity, your salespeople must be ready with a cold email sequence to pitch your product/services.

Ensure your cold email gets opened by not wasting the golden opportunity your contacts have given you. Leverage the mutual connection you have and name-drop in your subject line. Doing so gives you an excellent opportunity to gain your prospect’s trust.

Need an example of how you can do this?

Here are a few ideas to help you out:

  • [Name] suggested I reach out to you.
  • [Name] loved our product. He thinks you will too.

Using your mutual connection’s name will do all the heavy lifting for you. For this type of subject line to work, however, you must be sure your prospect will know who you’re talking about. If you’re not sure, you can use the preview text to give more context.

Here’s one I received the other day from app builder platform Fliplet:

You might not recognize the name, but Mayer Brown is a well-known law firm. As most of Fliplet’s clients are in this industry, mentioning that this company is attending their event lends it credibility.

The direct ask subject line

Sometimes the best way to get your cold email to be opened is by using a subject line that gets straight to the point. Some people appreciate this approach as it doesn’t waste their time. They know precisely what your email is about, and if they’re interested, they’ll click through. Here’s how the direct ask works in cold email subject lines:

  • Need help building your sales pipeline?
  • We’ve designed an ATS we think you need to try.

The trick with the direct ask is that you must either trigger a pain point your prospect has or highlight a benefit they will get from your product/service.

Here’s an example I received recently. Risk is always a massive factor for small business owners looking to scale up, and this simple offer will resound with many of them.

Curiosity invoking subject lines

Whether you’re in B2B or B2C, one thing is sure—your prospects are human beings.

What does this fact have to do with cold email subject lines?

Well, everything.

One aspect of human nature I’d like to zero in on, is curiosity. It’s one trait every human being has. And that’s why people fall for clickbait. Don’t get me wrong—I’m not an advocate for clickbaity subject lines. However, you can use the main ingredient of clickbait (curiosity) in an ethical way in your subject lines. Take a look at these examples:

  • These are the tools giving [company/competitor] an edge.
  • Want to know the 3 things successful B2B buyers do?

For your curiosity-invoking subject lines to work, they must not only appeal to your prospect’s sense of curiosity, but must also align with the message of your email. Failure to do so will leave your prospects feeling cheated into opening the email.

Here’s a good example from AI writing tool Ryter, since I would be keen to know what the most requested update is, especially as I don’t remember requesting one!

Data-driven sales prospecting subject lines

If there’s one thing that will grab your prospects’ attention, it’s data. People want to see evidence of what your product can do. And the best way to achieve this is to show them facts and data. And what better place to feature that data than in your sales prospecting cold email subject line?

  • [Tool] helped [Company] increase their conversion rate by XX%.
  • Want to boost your ROI by XX%?

Data gives your prospects proof that you’re not all talk. It’s evidence that what you’re selling will deliver the results they’re looking for.

Follow-up email subject lines

Not everyone will respond to your cold email. Most personalized cold email campaigns average a response rate of 9%.

It’s numbers like these that make many people shy away from cold emailing. But there’s a simple trick to push those figures up and get better conversion rates, too.

That simple technique is following up.

And just as the case was with your initial cold email, your follow-up email campaign must have a well-crafted subject line if it’s to be effective.

Here are a few approaches you can take:

“Do you have any questions about…?”

  • Have any questions about [topic addressed in the previous email]?

One of the reasons this subject line works well is that it reminds the prospect about your first email. It also gives them a gentle nudge to interact with you by asking any questions they may have. This helps them overcome any reservations about your product.

Here’s one I received a few days ago. It works because it suggests that the person is expecting my response, which encourages me to respond:

“The offer still stands.”

This type of follow-up email works well if your initial email contained a special offer for your prospect.

  • Jim, your offer for 50 free leads still stands.

Any variation of this subject line works as it reminds your prospect that they can try out your product without having to make a significant commitment. Everyone loves freebies and special offers, so this follow-up email reinforces the fact that you still have one available for your prospect. You can even add some more incentives to sweeten the deal and encourage a faster response.

“You don’t want to miss this.”

One of the best places to use FOMO is in a follow-up email.

  • Don’t be the guy who bought a pizza with $446 million worth of Bitcoin.

Hinting at a missed opportunity that will cost them a fortune down the road is a great way to inspire your prospects to open your follow-up email. After all, no one wants to be seen as the loser who messed up big time.

Here’s another example:

  • Are you in? We’re soon closing the doors on [offer].

It’s effective because it highlights that time is running out, and it will make your prospect think twice about missing the opportunity you’re presenting.

The “double whammy” follow-up subject line

If a prospect doesn’t open your email the first time, you may have to take a more radical approach the second time around. One way you can do that is by using the “double whammy” subject line. This is simply a subject line that appeals to two or more elements of human nature.

Here’s an example:

  • I’m no Heisenberg, but the deal I cooked up for you will make you high.

The above example contains humor and triggers curiosity. Such subject lines, when done well, have a “magnetic force” that compels the recipient to open the email—just to satisfy their curiosity.

But don’t stop at the subject line. Your email content must also continue to captivate them in the same manner. One way you can do this is by using personalized images in the email itself. Doing so will ensure your prospect remains engaged with your email, which increases the chances of them considering your offer.

6 Professional Email Subject Line Examples

As I said in the beginning, cold emails aren’t just reserved for sales. You can use cold emails to achieve different professional goals. And yes, the subject line still matters.

Let’s briefly look at a few professional email subject line examples used in settings that don’t involve selling.


Cold emails play a significant role in recruitment. It features on both ends of the spectrum—headhunting and applicants looking for employment opportunities. Here are a couple of examples of subject lines that work well in this vertical:

  • Heads up! [Company] is hiring, and I think you’re a good fit.
  • This could be the dream job you’ve been waiting for.

Here’s another example that’s very simple and straight to the point:


Other non-sales industries that leverage cold emails are those involved in research.

Researchers need a large pool of subjects to get more empirically accurate results. This requires reaching out to people and organizations they’ve never interacted with before.

  • Would you like to help the [industry name] advance?
  • Can you spare 5 minutes to answer a few questions concerning [topic]?

Event marketing

Want to ramp up the attendance for your next event (both live and online)?

Cold email can help you achieve this. Here’s an event invitation I received recently:

And here are some cold email examples to help you in this particular niche:

  • [Speaker] will revolutionize [prospect’s company].
  • Last year was awesome. This year [event name] goes epic.

The key to event marketing subject lines is to make your prospects excited about attending. Name-dropping certainly works, as it builds anticipation.

Using Personalized Cold Email Templates

Because cold emailing involves sending emails to many different prospects, personalization may sound like a daunting prospect. To make it easier, use personalized cold email templates.

Fortunately, being a cold email, it doesn’t have to be hyper-personalized. You only need to do two things to nail personalized cold emails:

  • Create templates for each target group/persona.
  • Research individual prospects and personalize an element of the email.

It’s with the second one that tools like Hyperise come in handy. They help you create personalized dynamic images for each prospect or business you reach out to. Personalized images to feature in your cold emails include custom screenshots, company logos, your prospect’s profile photo, and other visual representations.

Email example:


Armed with a cold email template for each of your target personas and some personalization tools, sending out cold emails becomes a matter of plug and play. Not forgetting your email service provider (ESP), of course, without which you can’t send automated campaigns.

A few tips to remember as you use cold email templates include:

  • Keep it simple. Don’t overcomplicate your template, as this creates more room for errors, particularly concerning personalization.
  • Research your prospects. Know your prospects and find out what their main pain points are. This will help you create cold email subject lines and messaging that’s relevant.

Warm Up Your Prospects with Cold Email Subject Lines

Cold email has a bad reputation amongst some, but it works—especially if you create cold email subject lines that encourage prospects to engage.

Using the tips above, craft cold email subject lines that will stand out in your recipient’s crowded inbox.

Crafted well, your cold email subject lines will warm your prospects to your offer.

Remember, your subject line determines whether your email will be opened or not, so give it the love it deserves.

If you have any comments or questions regarding cold email subject lines, feel free to drop them in the comment section below.