Google for the best cold email subject lines and you will get tens of blogs with titles like “20+ best subject lines…” or “150+ best subject lines….”

So what makes this blog any different? Well, I am trying to keep the list extremely small here with just 5 subject lines. And since the cold email world changes rapidly I am focusing on the fundamental principles that will stay strong even in 2024. 

But before I share a list of my favorite cold email subject lines let’s discuss what makes a good subject line and what changes do you need to keep in mind for 2024. 

Because once you have the basics covered you can come up with your subject line ideas without needing external help. 

Why sending cold emails in 2024 is different? 

2024 is probably one of the toughest years to be sending cold emails. With the explosion in generative AI tools creating personalized emails at scale became super cheap. Now, everyone is blasting emails at full throttle. 

Add to that a bunch of restrictions placed by ESPs, and a cool-off period in technology companies spending cold email sounds like a dead end. Here are the major reasons why cold emails are difficult in 2024.

Google and Yahoo restrictions on bulk email senders. 

Google and Yahoo announced new restrictions and compliance standards for bulk email senders earlier this year. And that included complying with authentication standards and reported spam rates. Now if you are one of those who are sending 5000+ emails a day you need to make sure that your user-reported spam complaint rate is less than 0.1% or 0.3% overall. That’s a tough ask. 

But even if you don’t send 5000+ emails a day you can be rest assured that Google will enforce stricter spam controls for lower volume senders too.  

Inboxes are flooded with cold emails. 

The average business professional was receiving 120+ emails a day and your cold email hides among one of these emails. With inboxes flooded with cold emails, likely, your message is never read despite you having the best offer in town. 

The economic downturn has shrunk budgets.

With generative AI and automation being prioritized over other spending businesses have shrunk their budgets for new technology spending. Or at least they are being cautious with where they are spending all their money. This makes it even more difficult to get a meeting with decision-makers and since they aren’t buying they tend to open fewer emails. 

Basics of a good cold email subject line for 2024 

With the above challenges, you need to ensure that your subject lines are something that inspires trust in your prospects. It should get through their mental spam filters and address their primary questions about the email - “Is this worth my time?” and “Is this important right now?” 

The first question’s answer depends on whether you have chosen the correct subject line and the second’s answer depends on whether you have created a good cold email prospect list. Here’s how to get to “Yes” for “Is this worth my time?”

Short, relevant, and personalized

Keep your email subject lines short, relevant, and personalized. Research suggests that shorter subject lines with one or two words have higher open rates than longer ones. While a short subject makes them feel that the email is casual and can be answered with a simple “Yes” or “No.”

Most people don’t want to miss out on anything that might help them get ahead in life. And that’s where personalization and relevance kick in to boost your open rates. When you keep the subject relevant to their professional needs they want to see what’s inside, personalization just adds that extra sauce. 

Doesn’t scream spam

Your email just doesn’t have to pass through the spam filters designed by ESPs. It also needs to pass through the mental spam filters of your prospects. Mental spam filters are harder to circumvent than algorithms because each person is different. 

A basic guideline is to not promise something sensational or make claims that you know will fall flat on its face. For example, don’t overstate your product’s capabilities. 

Straight to the point

Remember the objective of a cold email is to establish a connection with a stranger. You have never met this individual and most probably they don’t know about you or your product. The best way to establish a connection with such a person is to be straightforward. 

And that starts with the subject line. Make sure that your subject line indicates to the prospect that your message talks about something they care about. For example, if you are emailing a CFO about a better way to manage audits, just use “audits” as the subject or “internal audit” or “auditors.”

Examples of best cold email subjects for 2024 (750 words)

I have tested quite a few subject lines for my cold email campaigns and a few of them stand out. These are especially great at satisfying our earlier established objectives of keeping the subject - 

  1. short, relevant, and personalized, 
  2. not spammy and
  3. to the point. 

[service area]

You can just use your area of service or the product category as a subject line. It is to the point and if you have segmented your email list based on intent-driven triggers you might also be relevant and on time. 

This works because you don’t need to beat around the bush before sharing about your company in the email message. Also, with the requirement of creating emails with less than 50-70 words, it helps to address the area of concern in the subject line. 

A few examples would include - 

  1. Say you sell business intelligence software, a few subject lines could be “BI tool”, “BI & analytics”, “BI team”, “BI automation”
  2. Or you are a rep at the outbound software, a few subject lines could be “outbound automation”, “outreach software”, “sequencing tool.” 
  3. Or you might have a management consulting services business, and a few subject lines, in that case, could be “ESG”, “regulatory compliance”, or “training bandwidth.” These can vary depending on the area of your expertise/operations. 

[assumed pain point]

You can also lead with a pain point that your product or service solves for the prospect. It helps elaborate on why you are reaching out and makes clear that you will be talking about the problem in the email copy. 

If the problem is something that your prospect is facing right now or they want to address it soon, they’ll open your email. 

To do this successfully, you will need to create a mapping of your ICP/buyer persona with some of the problems that they might face. Some of these problems might be assumptions based on your buyer persona research. While others can be collected from user interviews, G2 reviews, industry reports, and from public forums. 

Continuing with our earlier examples - 

  1. For the business intelligence software, a few pain-based subject lines could be “report management”, “messy data”, “unstructured data”, “data loss”
  2. For the outbound software, a few pain-based subject lines could be “invalid email data”, “email deliverability issues”, or “follow-up mismanagement.” 
  3. For the management consulting services business, a few pain-based subject lines could be “compliance backlog”, and “ineffective training.” 

[mutual connection]

Seth Godin says in “This is Marketing” - 

People like us do things like this. 

Meaning people believe in tribes and they tend to do things that their tribe members do. With so much cognitive overload people’s trust barriers have gotten higher and strangers aren’t always welcome. And the only ones they truly trust are people who are like them aka their tribe. So when a colleague or a thought leader in their industry vouches for you, you are in the green. 

In fact, in the digital social era, this might be the best way to get past the mental spam filters. 

People buy from people they like and we like people who are like us. 

A way in which you can do this is - Use referrals and past colleagues or customers for credibility. Share how you’ve helped mutual connections achieve business objectives to pique curiosity.

[social mentions]

We love it when we are mentioned in posts or if we are important enough, get featured in a news article. The same applies to prospects who have been mentioned on a blog post, featured on a podcast, a social media post, or the latest news. 

When you remind your prospects of that achievement, their brain associates the email with a positive event. And we love to relive our best days. So, subconsciously your prospects want to open the email as an impulsive reaction. 

Here are a few ways to do it - 

  1. cite a blog they published.
  2. cite a blog they were mentioned in, use clay to run a Google search, and find blogs where they have been mentioned.
  3. cite a LinkedIn post on which they got a lot of engagement. 
  4. cite a recent podcast they were on. 


Mentioning the ideal customer profile of a prospect can work wonders in certain cases. This is because it shows that - 

  1. you have researched the prospect’s business very well. 
  2. you mean business because a subject so personalized can’t be a blast-email sequence.
  3. they might have something to gain from your message. 

But remember this works only when your product or service helps them - 

  1. get more users in their ICPs. 
  2. get more revenue from their ICPs or,
  3. helps elevate the user experience/service experience of their ICP. 

There are a ton of other ideas for subject lines and you can find more on how to write subjects that get high opens in our detailed guide here.