7 Email Marketing Subject Line Hacks

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Are you thinking of using an email marketing strategy to boost conversions and sales? Email marketing can be one of the best marketing tools you can use to engage your customers on a personal level. This can help improve your lead generation and eventually your conversions and sales.

Subject lines are your emails’ calling cards. Leading off correctly can make or break your email marketing efforts. But through simplicity, humor, controversy, questions, numbers, and a tiny dose of negativity, you can be a pro at subject lines. Add personalization, and you can lure audiences much faster to your service or product. 

Keep reading to learn more about the top seven subject line hacks you can use in your emails.

Keep Your Subject Lines Simple

We can all agree that time is money. A simple line can convey meaning that requires no time to decipher or open. 

When we say simplicity, we mean no cryptic language. Nor should we use anything a person has to “read into”. So, some good examples can be: 

  • “Your registration has been approved!”
  • “Your account has been successfully linked to your Gmail account!” 

As you can see, simple subject lines work well for readers already connected to your product or service in some way. They have also been the go-to lines for social media sites and e-commerce services. 

Try Some Humor

Humor may not be the best driver of behavior or consumer activity. But none of us would ever say that it does not drive curiosity. 

At the same time, it can brighten up anyone’s day. And we all know that while humor is not always a driver of behavior, positivity is.

For example: 

  • “Here’s an easy way to hide your content on the second page of Google.”
  • “Got wood? The Earth has less. Plant a tree.”

Create a Bit of Controversy

Subject lines that elicit a reader to form a certain opinion can lead to better opening times and rates. For instance, many would open an email with the subject line: 

“Android phones are better than iPhones because…”

Those who agree will open the email to confirm their biases. Those who disagree would like to see the main argument. 

Either way, you get more readers and more potential leads. 

Go Ultra-Simple With Single-Word Subject Lines

Minimalism is a buzzword in many fields today. It is an approach that can help you create frill-free subject lines in the spirit of conciseness. 

Like with simple subject lines, single-word subject lines work best for certain readers or customers. These are for customers already invested in the product in some way. 

Examples are: 

  • “Sale!”
  • “Coupon!”

Numbered Lists = Digestible Content

Numbered lists as subject lines foreshadow email content that is easily readable and in order. Numbered lists also spark curiosity for many readers. 

Though common, they can be very effective. 

For example: 

  • “Top Three Reasons You Cannot Sell.”
  • “7 Subject Line Hacks”

Capitalize on FOMO

Consumers usually have a fear of missing out (FOMO). Whether it is a service or a new diet hack, readers want to be in the know. And they want to experience things first hand. 

Creating a subject line that speaks to FOMO can leave customers wanting more. Here are some examples: 

  • “Hundreds of people are losing weight with this pill!”
  • Thousands of marketers are using this on-page platform!”


You may need some serious ID graphing for this approach, but it will pay off. 

Names can be too spammy or Big Brother-esque. Instead, you can target interests and regular clients. 

A personalized approach to subject lines creates engagement and a sense of intimacy. It tells your client that you pay attention to them. 

Use Any of These Hacks. Or Try All of Them!

Email marketing does not always need a fire-from-the-hip approach. By knowing your audience, you can use these hacks to create more engagement and higher opening rates.

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John Gardner

John Gardner is an expert email marketer and co-founder of Inbox Mailers. He specializes in email segmentation and improving overall deliverability, helping top brands and businesses optimize their email marketing strategy.