Tips To Create The Best Subject Lines For Cold Emails

Boost Inbox Logo Daniel Taylor
December 07, 2023
young lady reading book wearing green suit

Cold emailing is a powerful and popular technique for reaching out to potential customers, clients, partners, or influencers. One of the most important factors that determines the success of your cold email is the subject line. So, how to create the best subject lines for cold emails?

In this blog post, we will share some tips on how to write good subject lines for cold emails that get responses. We will also show you how to avoid cold emails from falling into spam. Let's get started!

What is a cold email?

A cold email is an email that you send to someone you don't know or have any prior relationship with, to introduce yourself, offer value, or ask for something.

Cold emails are different from email marketing, which involves sending mass emails to a large list of subscribers who have opted in to receive your messages. They are more personalized, targeted, and tailored to the specific recipient and their situation.

These kinds of emails also have a clear and specific call to action, which is what you want the recipient to do after reading your email, such as reply, book a meeting, sign up, or buy.

Some examples of cold emails are

However, cold emailing is not easy. You have to compete with hundreds of other emails in the recipient's inbox, and you have to persuade them to open, read, and reply to your email, all within a few sentences.

Tips to Write Good Cold Email Subject Lines

One of the most important factors is creating catchy subject lines for cold emails. The subject line is the first thing the recipient sees, and it decides whether they will open your email or not. A good subject line can make or break your cold email campaign.

According to a study by Finances Online, (2023), 64% of email recipients open emails based on the subject line alone. Therefore, you need to craft the best subject lines for cold emails that are catchy, relevant, and compelling.
Here are some tips on how to write good cold email subject lines that get responses.

1. Be brief

To write catchy subject lines for cold emails, it's important to be brief, clear, and engaging. Experts say the best subject lines are snappy, brief, and relatable. Aim to keep your subject line below 60 characters and 10 words in length.

This is crucial because most people read emails on their mobile devices, and long subject lines may get cut off and anything shorter than that might not convey enough information or value.

A brief subject line is also more likely to catch the recipient's attention and curiosity, as it leaves some room for imagination and intrigue. For example, compare these two b2b cold email subject lines:

The first one is too long and too specific, and it might sound too good to be true or too spammy. The second one is shorter and more vague, and it might pique the recipient's interest and make them want to know more.

2. Create curiosity

One of the best ways to make your subject line stand out and get clicks is to create curiosity. You can get the best subject lines for cold emails by adding the element of curiosity. It is a powerful psychological trigger that motivates people to seek new information and experiences. You can use curiosity to entice the recipient to open your email and find out what's inside.

There are several ways to create curiosity in cold email subject lines, such as:

However, be careful not to overdo it or use clickbait tactics that mislead or disappoint the recipient. Your subject lines for cold emails should match the content and tone of your email, and deliver on the promise you made. Otherwise, you might lose the recipient's trust and interest, and damage your reputation.

3. Personalize them

Personalization is another key element of a good subject line. Personalization means using the recipient's name, company, industry, location, or any other relevant information that shows that you know them and care about them.

It's about showing that you've taken the time to understand who they are and what they care about, rather than sending out generic, mass-produced messages. Personalization can make your subject line more appealing, and relevant, and increase the chances of the recipient opening your email.

According to a study, emails with personalized subject lines are 26% more likely to be opened than those without. However, personalization is not just about adding the recipient's name or company. You also need to customize your subject line based on the recipient's situation, needs, and interests.

For example, compare these two subject lines:

  1. "Hey John, I have a great offer for you"

  2. "Hey John, how to save 20% on your next flight to New York"

The first one is generic and vague, and it might sound like a sales pitch or a spam email. The second one is specific and relevant, that’s a good subject line for cold emails and it shows that you know the recipient's travel plans and preferences and that you have something valuable to offer them.

4. Use power words

One of the best ways to make the best subject lines for cold emails is to use powerful words. Words that evoke strong emotions, such as curiosity, excitement, fear, or anger. These words can make your subject line more captivating, persuasive, and memorable, and influence the recipient's behavior and decision.

One of the key things to consider when using powerful words is the emotion you want to elicit from the recipient. Different power words can trigger different emotions, and different emotions can have different effects on the recipient's behavior and decision.

You need to choose the power words that match the emotion you want to elicit, and the emotion that is appropriate for your email.

For example, if you are sending a cold email to offer a free trial of your product, you might want to elicit excitement and curiosity from the recipient. You can use powerful words that convey these emotions, such as:

These words can make the recipient feel more eager, interested, and enthusiastic, and make them more likely to open your email and sign up for your free trial.

You can use powerful words to spice up your subject line and make it more appealing and compelling.

However, be careful not to overuse them or use them in a misleading or exaggerated way. Your subject line should still be honest, clear, and relevant, and match the content and tone of your email.

5. Experiment with A/B testing

A/B testing is a method of comparing two versions of something to see which one performs better.

You can use A/B testing to test different subject lines and see which one gets more opens, clicks, or replies. By this, you are able to create the best subject lines for cold emails because A/B testing can help you optimize your existing subject line and improve your email campaign results.

To do A/B testing, you need to:

How to avoid cold emails from falling into spam?

Another challenge that you might face when sending cold emails is spam filters. The spam filter is decided by some algorithms that scan and filter emails based on certain criteria, such as the sender's reputation, the subject line, the content, or the attachments. Spam filters are designed to protect the recipient from unwanted, irrelevant, or malicious emails, but they can also block legitimate and valuable emails, such as your cold emails.

However, by using Boost Inbox you can warm up your domain. Warming up a new email domain is crucial to avoid spam filters, build a sender's reputation, and ensure email deliverability.

In conclusion, mastering the art of cold email subject lines can significantly improve your outreach efforts.
As we’ve seen, some tips for best subject lines for cold emails are being brief, creating curiosity, personalizing messages, using power words, and experimenting with A/B testing, you can increase the chances of your emails being opened and read.
Remember to warm up your domain to prevent your emails from being marked as spam. Implement these tips, and watch your cold emails become powerful tools for connection and engagement. If you have any doubts on how to be ahead of the email marketing trends for 2024? Get in touch with our experts.

What to read next

Yes, Boost Inbox is designed to cater to businesses of all sizes and industries.

Absolutely! Boost Inbox is compatible with most major email service providers.

The warmup process duration may vary depending on your email volume, but it typically ranges from a few days to a couple of weeks.

Yes, Boost Inbox offers dedicated customer support to assist you throughout the warmup process.

While it's possible, it's best to start the warmup process from the beginning with Boost Inbox for optimal results.