Subject Line Best Practices: 9 Ways to Boost Your Email Ad Open Rates

You’ve probably heard that you can’t judge a book by its cover.

But you’ve probably also impulse-purchased a book in an airport bookstore based 100 percent on its cover. While you can’t know everything about a book from its cover, it doesn’t hurt if it’s pretty enough to convince you to crack it open.

Dedicated emails are no different—while your subject line might not be the most important element, if it gets people to open, it’s worth devoting a little extra time to getting it right.

47 percent of email recipients decide whether or not to open an email based on subject line alone. So, yes, your recipients do judge a book by its cover. Keep reading for the best subject line best practices we’ve found in our work with advertisers.

1. Keep It Short

Of course, it should come as no surprise that you need to keep your subject line brief and to the point. With more and more people checking their email on mobile devices, you have even less real estate to work with.

Try to keep your email subject lines shorter than 50 characters to ensure that they register on different email platforms and devices. When in doubt, send a test email to yourself and see how it shows up on different screen sizes.

2. Inspire Curiosity

One of the most logical ways to earn an email open is to make a reader wonder about what’s inside. No need to go full clickbait, though—you can inspire curiosity without using the phrase “you’ll never believe”.

Instead, try piquing your audience’s interest by mentioning the kind of content inside your email without giving everything away. Try a subject line like “a surprise gift for you!” to catch your readers’ interest and stand out in their inbox.

3. Mention Your Offer

If you’ve gone to all the trouble to create a killer offer, don’t let recipients delete your email before they even get to see it. Don’t be shy about mentioning a great deal or fascinating ebook right in your subject line.

Try a subject line that gives a reason to open and take advantage of your offer, like “save 20% on your first month” or “free ebook for entrepreneurs.”

You probably won’t be able to give everything away in the subject line, but that’s just another great way to create curiosity in your readers.

4. Make it Urgent

If your offer is expiring, you can increase open rates by adding a sense of urgency to your subject line. This technique works really well in combination with mentioning your offer to create a compelling case why readers should open.

Edit your offer-focused subject line by adding a preface like “[Ends tonight!] Get our best selling ebook for free” or “This week only: save 20%.”

Presenting a reason for readers to take action now, instead of later, will help boost your open rates as well as conversion rates.

5. Focus on Action

You can think of a subject line a bit like a CTA—after all, in both cases, you’re trying to inspire a given action from a reader. That’s why one of the most important parts of any CTA is action.

Focusing on action allows a reader to see themselves taking part in it and inspires excitement.

Brainstorm ways to inject action into your subject line, based on what you know about your readership. It’s especially powerful if you can start your subject line with a verb, like “Cook dinner tonight.”

6. Ask a Question

It’s only natural to get interested when a subject line asks a question—especially when it leaves you wanting to know more, or second guessing your answer.

Test out questions that aren’t easy to answer right away, like “are you making these web design mistakes?” or “could your stock photos be hurting your brand?.” Instead of being able to answer quickly in their head and moving on, readers will be forced to stop, think, and (hopefully) click.

7. Delight Readers

In a world where readers open their inboxes to find hundreds of identical-looking subject lines every single day, anything you can do to make the experience better will help you stand out.

Get readers to engage and open your emails by turning your subject line into a place to provide surprise and delight. Try using a pun in your subject line, or incorporate an emoji in place of a word (you can copy and paste them from a site like GetEmoji).

Which would you rather click on: just another email, or one that makes you smile at your inbox?

8. Localize

If you know something that ties your audience together, like a geographic area, tailor your subject line to them. Anything that can make your audience feel like you’re talking directly to them will increase engagement.

If you’re mailing to an audience that lives mostly in New York City, for instance, you might include a subject line that references their location, like “New Yorkers: get your first order half off.” You could also reference local weather, sports teams, or cultural touchpoints in a certain area.

If you don’t know where your audience is, or they aren’t in the same place, you can still personalize based on what you do know about readers. For instance, you could mail to a list of graphic designers with a subject line like “The tips you need to keep your next design feeling fresh.”

9. When in Doubt, Test

Of course, when it comes down to it, what works for one brand may not work for others. That’s why the most important step is to test your own subject lines to come up with formulas that are winners for you.

Luckily, Paved makes it easy to track the effectiveness of your dedicated email campaigns with our tailored dashboard that shows your campaign results in real-time.

Track your open rates to get a sense of which subject lines work best for you, and which ones need to be reworked. Then, you’ll have the knowledge you need to scale your campaign strategy.

Subject Lines That Get Clicks

Now you have all the subject line best practices you need to ensure a high open rate on your next dedicated email blast.

Ready to simplify your entire dedicated email strategy? Sign up for Paved today and see how simple sponsored content can be.