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9 Tips for Writing Powerful Email Subject Lines

Updated on February 11, 2019.

Did you know that the average worker receives over 100 emails a day? That means there’s a Game of Thrones-style battle going on in every inbox to see who will make the cut and who will be banished to the spam folder.

So, what’s the best way to rise above the clutter?

It starts with a well-crafted subject line. According to MailChimp, one of the leading email and list building service providers, the most effective email subject lines are brief, descriptive, and include a compelling reason for the user to click ‘open’.

Knowing how to craft an eye-catching email subject line can mean the difference between the delete folder and loyal subscribers, so it pays to know key tactics to enhance engagement.

Read on for our rundown of best practices for effective email subject lines.

  1. Keep Your Audience (and Your Goals) in Mind

The most important point to keep in mind when you’re drafting an email subject line is who your audience is, and what action you want them to take.

Are you trying to make a sale? Offer a promotion? Or just reaching out to your subscribers? Your final goal will determine what info your subject line should include. Be clear about the value of your email, and what it means for your subscribers.

Here’s an example from the ride-sharing app, Lyft, promoting a new discounted price. Their subject line reads “Commute for up to 40% less with Lyft Line.” As a user of Lyft, I know exactly what I’m getting in this email communication and how it benefits me.

lyft customer email

  1. Localize and Personalize

One way to improve your email open rates and target a specific audience is with localization. Localization is when you personalize an email message for each specific recipient.

Try a message addressed to the recipient by their first name. By adding the recipient’s own name in the subject line, you build a feeling of rapport. An example to use for your own subject lines may be, “Hey Tom, ready for spring?”

Twitter is great at personalizing their email communications. They include your Twitter handle in the email subject line and in the email body copy. It’s subtle but helps their emails stand out from the rest of the clutter in my inbox by addressing me explicitly.

twitter customer email

  1. Test Keywords and Phrases

Don’t be afraid to test certain words and phrases to see how your audience responds. Tools such  as this free subject line rating tool helps you create the click-worthy headline. Another popular resource is CoSchedule’s Headline Analyzer.

If you’re comfortable with the idea of trying something new, give A/B testing a shot. A/B testing allows you to test and compare the performance of different subject lines, sending the winning subject line to the rest of your subscriber list to maximize engagement.

You can also analyze and compare different variables of your email campaigns, such as:

  • How does the day of the week impact open rates?
  • Does time of day influence email open rates?
  • Does including a corporate name boost engagement?
  • Does a subject line with an incentive work?
  • What’s the click-through rate of a linked image versus text?
  • What’s the click-through rates using a GIF?

By using sophisticated tools to track how users respond to different variables, you can boost the tactics that work, and revise the strategies which don’t.

  1. Keep It Short and Sweet

In today’s busy world, an email subject line that’s hard to decipher will get your email deleted. Your subject line should be readable at a glance. Accordingly to MailChimp, 28-39 characters was the “sweet spot” with the highest click rate in a study of 200 million emails. Hubspot says to aim for 50 characters or less to convey your message succinctly but clearly.

  1. Use Groups and Segments

By using groups and segments, you can send targeted emails to those interested in a specific piece or type of information. You can use data points you’ve already obtained from your customers, such as their area of employment, their interests, and their geographic location to create targeted messages they’ll want to open. By crafting unique email just for them, you’ll increase the odds they’ll open your message.

  1. Convey a Sense of Urgency

Urgency is a tried-and-true sales tactic for a reason—because it works! Phrases like “one day sale” or “24 hours left” encourage your readers to act right now. Use urgent language so your audience feels as though they must open your email immediately, or else they’ll miss out.

Here’s an example from Skillshare that not only conveys a sense of urgency but also tells exactly what the deal is that they’re offering and how much it costs.

skillshare email

  1. Offer Value

Use email to share something of value with your audience. This may be your new e-book or discount promotion. Let your audience know that by opening your email, there’s something valuable waiting for them inside. Your subject line is the teaser.

One caveat: Don’t promise something which is not included in the email. Deceiving your audience doesn’t earn any goodwill and will cause people to unsubscribe from your list.

  1. Use Numbers

Just as numerical lists are effective in blog titles, numbers are effective in email subject lines. Using the subject line “7 Reasons to Read this Email” will pique subscribers’ curiosity. Using numbers in your email subject line sets your subject line apart in a sea of words—so if you have something to number, try it out. Here’s an example from CoSchedule of this tactic in action:

coschedule email

  1. Engage With Questions

Asking a reader a question is a good way to get a response. Pose a question in your subject line to encourage your reader to open it. It doesn’t have to be a tough question–for example, “Why is Your House Not Selling?” or “What Weight Loss Mistakes are you Making?” The very nature of posing a direct question piques the reader’s curiosity and compels them to want to find out the answer.

By following the key tips we outlined above, you can start exploring email subject lines to find what works for your audience. By analyzing what’s effective and what’s not, you can be on your way to engaging subscribers with genius subject lines.

Last modified:  February 19th, 2019