Cold Email Subject Lines For B2B Sales - Best Practices

Anyone telling you that cold email marketing is easy is lying primarily because of the following two reasons:

  • You are out of nowhere writing to someone who barely knows you and who never expected you to reach out. 
  • Also, the recipient in almost 90% of the cases may never respond, so you don’t know why they didn’t warm up to your ideas. 

But despite these marketing barriers, companies are winning big through cold mail marketing. Today, we’ll focus on one area of cold email marketing that can generate incredible results for any business if improved. 

We’ll discuss Cold Email Subject Lines in detail to guide you in succeeding where most marketers fail. Optimize B2B cold email subject lines with effective strategies to enhance sales and surpass competitors. Maximize outreach potential.

What's A Cold Email?

It is a marketing strategy that involves sending an unsought email to a business prospect that the marketer doesn’t have a prior relationship. 

A cold email is targeted toward initiating a conversation with the prospect, engaging them on a problem you can solve, and providing solutions. It's far from a promotional email introducing your company to new customers. 

So what does it all entail? Find out below. 

Cold Email Message Strategy

So are all sales emails cold emails? Not exactly. A cold email is specific and targets a particular individual who directly benefits from a product your company is offering. It must thus feature the following key ingredients: 

Customized Message

Think of a sales email you received out of the blue from an unknown company. Did it sound like it was addressed to you or smelled like a generic email created by some AI bot to suit anyone? 

Also, did the sender sound like they are the only party capable of giving you valid help? This is all personalization means to cold emails. Any communication lacking this sensation immediately ends when the recipient receives the message. 

Validated Sender

Do you have ample social proof that the email recipient cannot help but open the email you just sent them despite them not expecting it? What authority do you have that compels the prospect to engage with you? 

People relate with who they can trust. So if you cannot guarantee social proof, then you don’t stand a chance to move the prospect to talk back to you. 

Solutions Packed Package

Everyone is Dealing with Something.  

It may qualify as cliche, but life is all about the small things. If you can find a way to exploit this, a prospect is waiting to talk to you at the other end. People will do whatever it takes to take the pain off their backs. 

And this is what your cold email should entail: an irresistible solutions-packed deal. 

Clarity and Conciseness

You’re dealing with a stranger who is probably not in the right mood to open every email that pops up on their notifications. And if, by chance, they open it, they don’t have all the time to read through junk trying to figure out what you’re saying. 

So do the necessary; keep everything short and sweet. 

Let the cold email communicate authority to help, but concisely, lest you come out as a gasbag with much fluff but zero substance. 

Short, precise, and intentional is always better. While some people will advise you to keep it below a specific number of words, we leave that to you to decide. But the rule of thumb is that you must avoid the temptation of going big at this juncture. 

Remember you’re trying to woo the respondent to interact for the first time with your email. So if it is extremely long, they will lose interest immediately as it will appear just like any other cold email. 

Also noteworthy, most of your leads will read emails from their phones. Therefore, a short cold email subject line invitingly fits on the screen and communicates volumes at a glance.


Don’t beg the prospect into submission, but it could be worse if you came out as corky. So learn to operate on the balance. The prospect will give an ear if they sense that you’re appreciative and ready to go down on your knees to propose the deal. 

A little gratitude here and there and a concession of susceptibility will make the recipient like you more. Come out as entitled, and nobody will be willing to read beyond the cold email subject line

Email Warm Up

Now that you understand what it takes to make a great cold email, don’t wake up the following day and start dishing out messages to thousands of prospects. 

If you try it, this could be the last time you’ll do so because all email service providers detest spamming. 

You can go for email warm-up tools, but these may only work in the short term. The ultimate solution is to start small and then scale up the number of emails you send.

Target the Right Leads 

You could have the best email subject lines for cold emails on the planet, but if you reach out to the wrong person, it’s all in vain. So where do you source suitable leads? Charity begins at home. So start with those you already know (those on your email list). 

Also, check out platforms such as LinkedIn for a profile of individuals interested in what you’re selling. 

How about buying an email list? Well, refrain from that, as you’ll be at pains to explain to the prospect where you sourced their contacts. Also, you risked being scammed into buying the wrong email list and getting no conversions. 

Why Do Cold Email Subject Lines Matter?

It is the first line of sight your prospect interacts with, and so if you get it right, you have already captured their imagination of the big things to come. You go wrong with the cold email subject line, and you’ve dug a grave for the business lead. 

Why are we saying this? Because the success of the email marketing campaign is primarily anchored on if the respondent is drawn to open the email. So a bland subject line and very few people will read what you’re selling. 

Statistically, it has been proven that personalization in subject lines is one of the best hacks. A plain subject line that elicits no emotion has a low open rate of about 37%. 

But if reasonably personalized while highlighting the recipient and the sender’s name, this can rise to 86.6%. 

So anyone who told you that the cold email subject line never mattered lied to you big time. But you’re now probably wondering what you should do to make things right. We’ll look at that in detail below. 

How To Write A Cold Email Subject Line

Don’t just write any email subject line that comes to your head; this part matters immensely in determining the click rate. Earlier, we highlighted the generic strategy for a cold email subject line. 

Let’s now see how to do the actual writing and what you must focus on to excite the prospect to check out your offer. 

Have a Connection

Personalization is the ultimate art of cold email subject line writing. And, there’s no better way to achieve this than telling the prospect how you know them right from the subject line. 

For instance, take a case whereby you’re contacting a referral prospect from a mutual friend. 

You need to mention that the primary connection between you and the prospect is the friend. It doesn't necessarily have to be limited to friends. For instance, you can talk about a shared event you attended with the prospect. 

Also, you can refer to any interest you share with the prospect. Check out the examples below. 

Hi Tyler, Corey Mentioned that you might like our services. 

Hey Jack, We’re green tea lovers too!

Are you planning to attend the Cyclers event in New York?

Ask-a-Question Approach

Engaging the prospect can also go a long way in giving them the vibes you’re in for an educated discussion they should join in. The rule of thumb is that the question must fundamentally focus on the prospect’s interests, goals, and current undertakings. 

Examples of this kind of format are as follows: 

Hey Sam, Would you like to hack Google Algorithm?

Jack, are you content with the performance of your website? 

Propose an Idea

The best email subject lines for cold emails efficiently initiate conversations that proceed into the body. Hence, selling an idea to a client will go a long way in triggering a response. 

But before they can respond, they will be compelled to open the email and read more about your idea, which is the whole point of a subject line. 

Examples include: 

Let us plan a meet-up to see how you can optimize sales. 

Here’s a secret of how (competitor) handled poor site rankings.

Provide and Offer

Get the prospect thinking about your proposal by proposing an offer or discount to lure them into giving you an ear. Make it sound like you’re giving them a great deal they shouldn't miss out on. 

Don’t lie if there’s no genuine deal for the client, as your company will appear untrustworthy. 

Examples of Offers Include: 

Take advantage of our 20% discount on all Hush Puppies. 

Hey Jack, your $30 free bet is awaiting you. 

Make It Sound Quite Urgent

There is a general tendency for prospects to be more drawn to cold email subject lines that communicate urgency. The logic is simple- We all like deals and discounts, and nobody wants to miss out on a good offer. 

Also, this sense of urgency compels the subject to opt against postponing the email opening. This is great in ensuring most respondents interact with the emails immediately after receiving them. 

Hey Jack, Your $100 free Stake is valid until midnight. 

Peter, Claim your Webinar Spot now. We’ve only 20 Slots Left!

Cold Email Subject Line Examples

We’ve just said above that personalizing the email subject line is one of the secrets to exciting the prospect to open the email. So let us look at some of the main formats you can undertake and explore their success in terms of open rates. 

I noticed something on {{company}}

It is a remarkable subject line that introduces a touch of a personal relationship between the sender and your recipient. Primarily, it informs them that you’re a genuine helper who wants to solve a particular problem the subject is facing. 

Nonetheless, given that it is super-personalized, you must do due diligence on the company to know what best serves the prospect. 

Should we explore?

This type of subject line heightens your prospect's curiosity, drawing them to click the email in anticipation of finding what exactly you want to explore. What’s it opening rate? Incredibly high. 

But the rule of thumb is to keep it simple and not use capital letters to catch the recipient's attention. They will appear too shouting and less attractive to the prospect. 

Also, there’s a tendency for spam messages to use the all-caps format, and you need to be different. 

Stand out. 

About {{employee_first_name}}

Take a case whereby you got a lead from an employee of a b2b prospect. It would be best if you mentioned this employee as it elicits curiosity from the other end. 

Immediately they receive it, they’ll wonder what the employee did, which will compel them to open the message. But again, here, you must do your homework as you’ll need to get the details of the employee right. 

Also, having a brief background of the employee helps as it dictates how you proceed with your email body. 

Quick Question {{recipient name}}

Again, this is an attention-grabbing subject line with all the ingredients for an improved open rate. Recipients are drawn to know what you’re probably looking to ask, so they’ll open the email. 

Ensure you frame your email body as a conversation to continue the tone you started on the subject line. 

[[Words from a social post]]

Say you saw a prospect rant on social media about a particular issue that they didn’t like. This is an opportunity to sell to them if your company offers solutions to the problem. 

It is one of the most compelling subject lines primarily because it shows you have interacted with the prospect very closely. But it's among the hardest to make because you primarily need to research each prospect you’re planning to approach extensively. 

about your company's growth

Who doesn't want their company to grow in leaps and bounds? It is the dream thing for every firm, which you can capitalize on when doing a cold email. It is a catchline that shows what is in for the prospect in the email. 

Anything to have them open the email does the trick. And by that, we mean even something as absurd as this. But again, you must know a thing or two about the company you’re writing about, lest you come out as a fraud. 

{{company}} X [[Your Company]]

A cliche line, right? Well, it is a simple way to call out your client and an outright way to tell them to spare a few minutes to check out what you got up your sleeve. It's old school, but it still works perfectly. 

This is because it communicates that you have something that could benefit both parties. And so, why shouldn’t the prospect check out what it is? 

{{company}} was mentioned on LinkedIn

This plays perfectly well primarily because it draws the prospect to hurriedly rush into the emails to check what the mention was all about. Psychologically, the prospect gains confidence dealing with your company as you come out as a partner deeply invested in their well-being. 

{{first_name}} - quick question (10.51 s reading time)

Where’s the catch in this one? If you said the reading time, you guessed right. The last part has everything and will, more often than not, work.  What you’re doing is telling the prospect you have great communication that will barely take their precious time. 

Most will fall for such a cold email subject line primarily because we’re inclined to check out anything that appears urgent and concise. 

Let's share our Take on (input subject matter)

Here, you’re trying to come out as an authority on the issue you’re addressing. Of course, it would help if you did a background check to identify what the client specifically wants to learn/assist with. 

It’s classical but effective. 


Anything that will excite the prospect to click on your email ranks as a great subject line. But to guide you on where to start, we have given you loads of hacks to guide you on this crucial step in marketing. 

In a nutshell, we advocate for personalization and a solution-packed subject line. Also, run tests to see what best fits your case, as no apparent template fits all scenarios. 

Even if it means being against some of the tips we have enlisted, go for it as long as it guarantees lead conversions. 

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