Bethany Santos
Author: Bethany Santos

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In sales, every single word counts.

It’s why great copywriters charge as much as they do. The words used in marketing material, how they’re arranged, and how they relate to the products and services the business offers can be the difference between an easy conversion and a quick bounce.

This idea is no more powerfully demonstrated than in the realm of email marketing.

We all get more emails per day than we can possibly read. Accordingly, we’ve developed incredibly efficient filters that instantly disregard content that isn’t valuable to us.

And the main thing that determines whether or not an email is getting opened and read or sent straight to the trash? The email subject line.

So, we’re here to tell you not to regard your subject line as an afterthought. As the key determiner in getting your emails opened and read, it’s your bread and butter.

Allow us to explain further.

Why Are Email Subject Lines Important?

Did you know that most email recipients (64%) decide whether or not to open an email based on the subject line alone?

Surprisingly, only a minority (47%) of email marketers test their subject lines before sending them out, according to FinancesOnline.

By failing to A/B test their subject lines, the misguided majority of email marketers are missing out on a potential 27% increase in their click-through rate (CTR).

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Not everyone has the skills to craft a brilliant, conversion-boosting subject line, even when using ai copywriting tools. But everyone can appreciate the power that good ones have in increasing sales and act accordingly.

This is why we’ve gathered 20 of the most compelling email subject lines to use to boost your open rates and increase your sales and improve your overall saas marketing strategy.

But first, let’s go over some essential email subject line best practices so that you can implement our subject line examples in a way that complements your business.

Email subject line best practices

  • Be brief: This is our #1 tip for a reason. When drafting email subject lines, keep them short and punchy. Not only is there limited space in an email subject line, but your recipients are scanning yours among a hundred other ones, all competing for their attention. By being brief, you increase your chances of being seen and understood.
  • Communicate your main idea: Whether it’s a sale, new product announcement, or personal discount code, you should make every effort to express the core reason behind the email clearly and succinctly in the subject line. Being overly cutesy or cheeky in a way that undermines the idea behind the email is the wrong way to go.
  • Minimize punctuation usage: Of course, punctuation structures the text to make it more readable. But, use too much of it, and your subject line looks like spam, which will destroy your email deliverability. Besides, if you’re following rules #1 and #2, you shouldn’t need too much punctuation anyway.
  • Get personal: It’s well understood by now that adding elements of personalization, usually in the use of first names, increases open rates. If you’re using competent email marketing software, there should be a feature that allows you to automatically include the first names of each member of your audience in your subject lines.

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  • Use emojis sparingly: While the jury may still be out on this one, some evidence suggests that sparing use of emojis in email subject lines increases open rates. But, oppositely, overuse of emojis is likely to lead to a perception of your email as spam, so be conservative with your usage by limiting it to one emoji maximum.

With that covered, let’s move on to our suggestion of the 20 most powerful email subject lines to use specifically for increasing conversion.

5 Time-Based Email Subject Lines

These subject lines are designed to create a sense of urgency in your clients and customers, encouraging them to act quickly, and are perfect for any eCommerce business.

40% off sale ends TONIGHT

Catch these deals before they disappear…

One week left to take advantage of our Summer Sale

[NAME], don’t miss out on these reduced items

Today only: 30% off selected items 😃

If they are familiar with you and your offerings, a limited-time offer will excite and entice your audience, and a subject line like those above will be all it takes to get them to open your email.

However, they are less effective if the audience is unfamiliar with your business. The subject lines are heavily sales-focused, and your audience is not primed to value your offerings at this stage — so save them for your most loyal customers.

5 Curiosity-Based Email Subject Lines

These subject lines are informationally incomplete. They are written to introduce an exciting idea but leave the key information within the main body of the email to encourage that all-important open.

Our newest product may surprise you…

You’ll either love this or hate it 👀

Why we’re giving away our product for free

6 Reasons to start buying your Christmas gifts in June

[NAME], does this suit your style?

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Sure, the style of these curiosity-encouraging email subject lines may strike you as a bit like clickbait, but there’s a reason why clickbait is still used as much as it is in eCommerce. It’s extremely effective at generating clicks even more when you just created your online store. Something in the human psyche needs the answers to these questions.

The trick to avoiding the bad rep of “clickbait” is to actually provide valuable content within. So, if you use “Why we’re giving away our product for free,” there better be a competition and a legitimate chance of winning it waiting for your customer.

5 Re-Engagement Email Subject Lines

Re-engagement is a concept in email marketing that aims to revitalize a once active customer or client (one who was engaging with your business by purchasing products or arranging appointments) who seems to have lost interest.

They usually involve offering either a solution to a problem or showing good faith and encouraging loyalty to the business but don’t strictly have to. Here are some examples.

Here’s a 10% off code for the product in your cart

Are you still interested in [PRODUCT]?

Tell us where we went wrong 😕

It’s been a while! Here’s a discount just for you

Your account will close in [X] days…

They might have thought you were too expensive, your products weren’t relevant, or they forgot you existed. There’s a re-engagement email subject line for each that aims to solve those customer problems and get them back.

At the very least, for a customer committed to leaving you for a competitor, you can always ask for constructive feedback to ensure it doesn’t happen again.

5 Solution-Based Email Subject Lines

Fundamentally, it’s your business’s job to solve the various problems that your customers and clients face, whether it’s having a nice dress ready for the summer season or sticking with learning the guitar and everything in-between. 

These subject lines distill those problems into one snappy sentence, agitating the customer ever so slightly and making them quickly realize that you’re there to solve that problem in a few clicks. 

How to feed a family of five for 10 bucks

Layering clothes the RIGHT way this fall season 🍁

Have this genius email template on us

Your website could be 3x faster with these simple fixes

Beauty or functionality… Why not both?

Of course, both the problems and solutions have to be tailored specifically to your customer’s needs and the business's offerings, and the most powerful solution-based subject lines will be the ones that solve relevant problems most effectively.

So don’t ignore the power of in-depth customer research before drafting up your solution-based subject lines.

How To Increase Sales With Email Subject Lines

Thankfully, there are many ways to do this, most of which follow the key principle of marrying the existing solutions of the business with effective and creative copy.

In an email subject line, you’re trying to show your awareness of customer problems and the various ways in which the business offers a solution.

Experiment with a few different versions of subject lines that do this, apply our five best practices for email subject line writing and A/B test to figure out what’s most effective, and you’ll be good to go!

Make Your Email Marketing Profitable