Cold Email Subject Line Best Practices (With Examples)

You have under 8 seconds to convince someone your message is worth reading.

If you haven’t caught your lead’s attention within that time frame, you’ve lost an opportunity.

In this article, we break down the best practices for cold email subject lines that will help you get more responses from great leads.

For each best practice, we’re also going to show you examples of subject lines that incorporate it.

Let’s jump into the article.

Why do Cold Email Subject Lines Matter?

Two-thirds of people say they decide if an email is spam based on the subject line alone.

If your subject line doesn’t resonate with your recipient you’ll end up in the spam folder. You’ll lose an opportunity to talk with a great lead and your message will stay unread.

Campaign Monitor found that the average open rate for email marketing is just 17.92%.

Since cold email is one of the original digital sales tactics, it’s harder than ever to stand out in your recipient’s inbox.

Cold Email Subject Line
All tactics lose effectiveness over time

You can’t use email subject lines from templates that were published years ago. Every other sales team is using those templated subject lines, and you won’t stand out.

While there are no set rules to cold email marketing, you need to ensure your message is personalized and highly relevant to your recipients. With that said, let’s look at the best practices.

Cold Email Subject Line Best Practices

Before proceeding to the part of the article where we show you the best practices, it’s worth mentioning that none of these will work if your email list is bad.

You need to be emailing the right people.

You can use DemandScience to source and download up-to-date, GDPR compliant B2B contact data for leads in almost any industry across 90+ countries.

A well-segmented list will also help you ensure GDPR compliance as you can prove that recipients have a legitimate interest in your message.

A good email list ensures every lead will want to hear your pitch.

Then, you need to send them an email that’s going to resonate with their pain points and encourage them to take action.

When we see people struggling with cold emails, often it’s a problem like that of product-market fit.

You wouldn’t expect someone to buy your solution if they weren’t a great fit for it. In the same vein, you can’t expect an unqualified lead to open or reply to your email.

Now, let’s jump into the best practices.

1. Make Sure They’re Personalized (Within Reason!)

The first rule is to make sure it’s personalized.

Your value proposition needs to be relevant to the recipient, and your copy needs to pique their interest.

One popular tactic is to include your recipient’s name. This can work, but it’s also the most obvious tactic. You risk blending in with the countless other marketing email subject lines that start off with the recipient’s first name and won’t stand out in your recipient’s inbox.

A more powerful way to incorporate personalization in your subject line is to be specific.

Mentioning their product, a talk they gave at a conference, or an article they published are all great ways to show you’ve done your research and care about your lead’s time.

Subject line examples:

  • Follow up to [their content] on [topic]
  • [Name], [question]?
  • Congrats on [recent success for the company or person]!

2. Keep Them Brief (sometimes)

The average email subject line length is 43 characters. With every extra letter you risk diluting your message, so the general rule is to keep your subject line short.

Number of characters for subject line
What type of subject line do you respond to?

42% of emails are opened on smartphones or tablets, and they usually cut the subject line after 33-43 characters.

So, it’s in your best interest to keep your subject line short enough to show fully on mobile.

However, if you have a very specific ask, then it might be worth expanding, even at the risk of it being cut off on mobile. data found that subject lines between 98-111 letters actually had a higher open rate (54% open rate) than subject lines between 29-45 characters (33% open rate).

Subject Lines comparison
Long subject lines can work just as well as short ones

That’s a stark contrast to the usual data showing that short subject lines outperform longer ones.

So, what we can take away from this?

It’s all about specificity.

If your message is long but speaks directly to your recipient, hitting on pain points that resonate with them, then the subject length doesn’t matter.

Brief subject line examples:

  • [Name], interested?
  • Time for a call?
  • Need help with [pain point]

Longer subject line examples:

  • Growing [company]’s [KPI] with [your solution]
  • Met [mutual connection] at [event] and they told me you’d be interested in this

3. Take Advantage of Referrals

It goes without saying that referrals are powerful.

If you met someone at a conference or were pointed in their direction by a mutual contact, then mention that.

When testing various iterations of cold email subject lines, LeadGenius saw an 86% open rate when using a subject line structure like this:

If you were referred by someone, make sure to mention them

Seeing open rates that high is rare, but wouldn’t you open an email that mentions your friend or colleague?

Subject line examples:

  • [Mutual contact name] told me to reach out
  • Met [mutual contact name] at [event]
  • [Mutual contact name] said that [company] might be interested in this

4. Don’t Use Clickbait

This sounds obvious.

But how often do you receive emails with subject lines that are purely designed to get you to open it and don’t provide any real value?

Using false promises or clickbait can increase open rates in the short term, but they’re also going to increase the number of emails that get sent to the spam folder.

Clickbait removes any trust the recipient would have in you, and being reported for spam will hurt your email deliverability in the future.

Subject line examples to avoid:

  • Grow your revenue by 1000x with our new product
  • This email is the key to your future success!
  • You’ve won the lottery

5. Provide Value

The more value you can show in your subject line, the better.

What does ‘value’ mean **in this case?

Well, it’s anything that your recipient cares about. It could be a range of things such as:

  • Growing their lead pipeline
  • Increasing revenue
  • Reducing churn
  • Improving their data security practices

Essentially, ‘value’ is anything that will make your recipient’s life better in some way.

Subject line examples:

  • Reducing churn at [company]
  • Some thoughts on growing your lead pipeline
  • Useful resource on improving your [KPI]

6. Create FOMO

Creating fear of missing out (FOMO) is a commonly used copywriting tactic. And, it’s popular for a reason.

To use FOMO effectively you need to be honest with your prospect.

Here are some effective ways to use FOMO:

  • Offer an exclusive offer such as a reduced price
  • Highlight missed opportunities if they don’t use your solution

As we’ve mentioned, you need to maintain trust with leads, so don’t try to create artificial FOMO by offering false promises or made up offers. Down the line, your prospects will feel misled or lose the trust they had in you.

Subject line examples:

  • Limited time discount just for you
  • Don’t let [company] miss out on sales
  • Don’t miss out on sales on [relevant holiday date for your lead e.g. Black Friday]

7. Ask Questions

Your cold emails should have one goal.

In most cases, that’s to get a reply.

While your email body copy (link to new article on email copy) will play a large part, your subject line is what ensures your email gets opened.

Asking a question in your subject line will frame the email for your prospect, get them thinking, and most crucially, get their interest.

Subject line examples:

  • Would growing your lead pipeline by 10x be valuable?
  • Can you help me with this?
  • Does [company] need help with [something you can help with]?

8. Focus on Your Segmentation

As we mentioned above, you should be approaching cold email with a well-segmented list.

This gives you have a huge opportunity to focus down on what your persona (link to B2B persona article) cares about.

Subject line examples:

  • Solving [specific industry pain point] with [your solution]
  • Getting more leads from [your lead’s ideal customer]
  • Connecting with customers in [your lead’s location]

10. Don’t Just Follow Advice from Blog Posts

Now, it may look strange seeing this advice here. After all, this is an article on cold email subject lines.

However, you should know your leads and market better than anyone, and you’ll know what your leads want to hear.

If you’re seeing success with a subject line that isn’t listed in this post, then keep using it. Don’t switch a successful strategy just because we suggest it.

Wrapping Up: Best Cold Email Subject Line Examples

With these best practices and cold email subject line examples, your next email campaign will bring great results.

With our recommendations and your unique knowledge of your buyer persona(link to B2B buyer persona article), your cold emails will grab the attention of your leads.

If the only step left is to source your email list of leads, then reach out to someone on the DemandScience team to discuss how we can help!