6 Email Subject Line Formulas Guaranteed to Boost Your Open Rate
Email marketing is a powerful way to connect with customers and get sales. But no matter how well your email content is written, it won’t matter if people aren’t opening your emails to start with. That all comes down to your subject line.
Now, you don’t need to be a creative genius to get your emails opened. But there’s also no magic template that’s guaranteed to make you a millionaire. Start by using these six email subject line formulas as your guideline, then A/B email test variables to figure out what your list responds to the most (Kartra can automate that for you by the way), and you’ll be on your way to watching your email open-rate soar.
1. Ask a question
This is a classic trick many email marketing campaigns utilize, but it has to be used with some strategy.
Sure you can ask a question like “Excited for the holidays?” But that’s unlikely to resonate with most readers. Instead, try to think of questions your audience might legitimately wonder about
Sure you can ask a question like “Excited for the holidays?”
But that’s unlikely to resonate with most readers. Instead, try to think of questions your audience might legitimately wonder about
“Should you skip dessert at Thanksgiving Dinner?”
“Are you drinking too much coffee in the morning?”
“When is the best time to say I love you?”
Just make sure this first impression relates to your business and the content inside of your email.
2. The Shocking Subject Line
If you’re walking down the street and you see someone decked out in a full-on Sparkly Elvis costume at 9 am, are you going to notice? Probably. What about the guy in the business shirt and tie drinking his coffee? Less likely.
You notice the Elvis because it’s unexpected and breaks through the clutter (unless you live in Vegas that is). And a good email subject line is similar.
Now, this could be a shocking statement:
“Instagram is dead”
Or just a shocking phrase. Our “DAMMIT DAMMIT DAMMIT” and “SCREW THE WALL” subject lines fit neatly into that category. This is also a great place to play with negatively-phrased subject lines like:
“DON’T OPEN THIS EMAIL”
“Stop making this HUGE error”
However, we offer a small word of caution on this subject line style. The things that are likely to get the most attention may also get you a couple of peeved readers as well. Our customer service team definitely got a mouthful from a select few after we sent out our “DAMMIT DAMMIT DAMMIT” subject line.
This is good though because research has found that polarizing branding actually performs better. Sure some people will be upset, but others will be super FOR the risk you took. Much better than being the bland toast brand that no one can remember the name of.
3. The How-To Subject Line
If ever there was a classic formula for digital marketing headlines that work well on both landing pages and emails alike, it’s the How-To formula.
“How to make him fall in love”
“How to get 1000 new customers in a week”
“How to double your earnings in under a year”
You get the idea. The key to these subject lines is to focus on a benefit, not the work involved. No one wants to think about “How to write code,” but the benefit they get from writing code: “How to earn thousands with one skill.”
To crank this formula up a notch, we suggest adding a without section at the end:
How to [BENEFIT] without [PAIN]
“How to lose weight without doing any cardio”
“How to prevent aging without the expensive facials”
4. The Curiosity Gap Subject Line
The curiosity gap formula plays on peoples’ innate need to know. You tease a bit of information to pique their interest and then hold back, letting the reader know they need to open your email to find out.
Our subject line “The single best way to get customers, PERIOD” did just that. It teased that we knew the best way to get customers, but we didn’t say what it was. They needed to read to find out.
Other examples of this formula could be:
“We were amazed at how well THIS worked”
“We’ve got a surprise for you!”
This type of subject line performs especially well when you pair it with your reader’s specific pain points:
“15 Bizzare Tricks To Sleep Better”
5. The FOMO Subject Line
Speaking of pain points, you don’t want to miss out on this solution! If you’re not familiar with the term, FOMO stands for Fear Of Missing Out. It’s an innate psychological drive — people are afraid that they will miss out on something. And you can tap into that with your subject line.
To do this, you want to create a limited-time offer and add scarcity and urgency to your subject line (and if you have Kartra, you can even add a ticking countdown timer inside your email).
Examples of scarcity email subject lines include:
“Don’t miss your last chance to save on Black Friday deals”
“Uh-Oh Your trial is expiring”
“[URGENT] You’ve only got 6 more hours”
“Today Only: Get 50% off Access to All Webinars ”
Basically, you just want to induce a sense of urgency. You can do that by literally including the word “URGENT,” or other words like “FINAL WARNING,” “IMPORTANT,” etc. This formula also sets you up for an easy follow-up email with reminders.
6. The Numbered Subject Line
Numbers break through the clutter and give a concrete feel to things. You’re attracted to titles with numbers — you clicked the link to this 6 subject line listicle after all.
And studies have backed this up. A few large companies have tested including numbers in their subject lines vs not and every time, they get higher open and response rates by including numbers or stats.
This is such an easy thing to do too. Instead of sending “How To Get More Likes On Instagram” send an email that says “8 Ways To Get More Likes On Instagram.” Other examples of this tactic include:
“How to save $290 extra every month”
“33% of people say NEVER do this”
“23 Reasons You’re Not Succeeding”
Some of Our Best Email Subject Line Examples
Now, if we’re being honest, some of our best subject lines broke some of the classic rules. And others they followed. To show you how you can get creative with these formulas, here are our top 10 performing subject lines from the past year or so:
- ⛔️DAMMIT DAMMIT DAMMIT
- Don’t make assumptions
- This is ridiculous.
- Behind the scenes (breaking the “law!”)
- SUPER IMPORTANT AND AWESOME (in all caps, even!)
- The single best way to get customers, PERIOD
- that’s how they GET YOU. (and a confession …)
- NAME – New training for you
- How to bring home the benjamins?
- Screw the wall
(Looking for inspiration beyond subject lines? Explore these email marketing examples to see complete campaigns that drive engagement.)
A few things we learned:
—> We found subject lines that use emojis can break through the clutter, although this is becoming a more common practice so be wary.
—> Including a name added a touch of personalization that people couldn’t help but click.
—> And using subject lines that were framed negatively (ie: DON’T OPEN, as opposed to OPEN ME), tended to have higher open rates.
A/B Testing Your Email Subject Line
Email A/B testing is the process of sending two different versions of an email to segments of your email list in order to determine which version ultimately will convert the best—you can compare subject lines, preview text, email copy, call-to-action, and more.
Also referred to as split testing, this marketing strategy can provide valuable data on the email templates that connect best with your unique audience. For tips on how to do A/B testing, as well as what it is and why you should do it, click on the article we just linked!
A Few Tips on What NOT to Do
1. Don’t Be Spammy
We are all about using creativity to get a reader’s attention but beware of using clickbait subject lines that convince people to open emails and don’t deliver on what they promise. This practice is likely to land you in the spam folder, rack up unsubscribes, and ultimately affect your deliverability, especially if you’re sending out cold emails. Make sure your subject line clearly relates to the body of the email so there are no unpleasant surprises.
2. Don’t Overuse Exclamation Points or All Caps
Punctuation and capitalization can be effective at attracting attention, but be judicious with emphatic formatting—know what we mean?!??!?! Too much of it can feel spammy to your email recipients – see point one!
3. Don’t Forget to Test Your Subject Lines on Mobile Devices
What catchy email subject line will you write today?
You may have noticed that some of the subject line formulas overlap, and that’s perfectly okay. You can add numbers and scarcity, or how-to and curiosity. Mix and match and figure out what works for you.
But the real key is to test, test, test, and to look at your analytics. Because, while we wish email was one-size-fits-all, the truth is, every audience is unique. The best way to test is with Kartra. You can set up automatic subject line split tests and Kartra will let you know the clear winner. You can also easily track the open rate, spam rate, click through rate, and goal conversion rate of every sales email and email newsletter you send.
And then, maybe this time next year, you’ll be able to tell someone else what YOUR best 10 subject lines from the year were.
Interested? Try Kartra today.
About Kartra
This blog is brought to you by Kartra, the all-in-one online business platform that gives you every essential marketing and sales tool you need to grow your business profitably – from sales pages and product carts to membership sites, help desks, affiliate management and more. To learn how you can quickly and easily leverage Kartra to boost your bottom-line, please visit kartra.com.
