Less than a second. That’s how long it takes a person to decide the fate of your email. In the worst of scenarios, they’ll send your message to spam … and nobody wants to end up in spam. Especially when your success in marketing hinges on you getting emails opened, read, and acted on. (See what we did there?)
But of course, the challenge is that a single sentence dictates everything. And that sentence is the subject line.
Research shows that 69% of email recipients report emails as spam based solely on the subject line.
In general, the subject line should be:
- Succinct
- Benefit focused
- Accurate about what’s inside the email
A great subject line can also be clever — and maybe even a bit unusual. Keep in mind these are not hard-and-fast rules. Your audience will always tell you what works and what doesn’t with their clicks, so follow the data.
And if you haven’t collected data yet, don’t worry! We’ll help you get started with 12 best practices for email subject lines. Let’s start with the basics:
Should Email Subjects Be Capitalized?
Whether you capitalize every word or just the first word is up to you, but consistency is key. It’s part of your brand’s signature style, and people will come to recognize it. Also, double-check your email subject lines for spelling and grammar to maintain professionalism.
Focus on the Benefits of Your Subject Lines
Why should your reader care? Don’t make them guess the benefit of opening your email. Spoon-feed it to them. We’ll give you an example:
“Learn How {Customer Name} Increased Open Rates 77%”
The benefit is clear: “we’re going to show you how this customer increased their open rate and help you do the same.”
Also, you’ll want to overdeliver on your subject line in the email content. Otherwise, the next time you land in the inbox, your reader will pass you by (or worse, mark you as spam!).
And by the way, that 77% open rate is a true story; you can check it out here.
Keep Your Subject lines Active
With limited space in email subject lines, using action words like “get,” “watch,” or “join” can enhance their power. For instance, if you have an upcoming webinar, consider:
“Join to Learn How to 10x Email Open Rates”
Here, you’re telling the reader exactly what to do while promising specific value.
Best Practices for Email Subject Lines … Make Them Short
You might write a juicy subject line but you’ll face performance issues if it’s too long. Email providers have specific limits to how much text they’ll display, which can threaten to chop off part of your message. Here’s an example:
Long subject line: “Join to Learn How {Company Name} Doubled Revenue and 10x Email Open Rates”
What your reader actually sees: “Join to Learn How {Company Name} Double…”
A big difference, right? You lost the best parts of your message.
A good rule of thumb? Keep your email subject lines to 50 characters or less.
Good Subject Lines for Marketing Emails Avoid Spammy Words
Spammy words earn you a one-way ticket to the junk folder. And here’s the worst part. Machine learning is watching you, so if your emails habitually get marked as spam, getting back into the inbox will be hard.
A few potential trigger words to avoid:
- Free
- Act now
- Offer
- Get it now
- Exclusive deal
- Get started now
- Apply now
And watch your use of symbols, emojis, and all caps. They can quickly make you look spam-like to both readers and the ISPs. So know your audience, avoid spam trigger words, and continue to test email subject lines to see what users like and what they don’t.
Don’t Pretend to Know Your Audience
That includes adding a “FW” or “RE” in your subject line or trying to be mysterious (“You won’t believe this …” or even worse, “Hi”). These are bush league tactics that “consultants” want to sell you on but that never result in meaningful relationships with your audience.
Use Numbers in Your Email Subject Lines
Subject lines with numbers lead to 57% better open rates. Instead of vague promises, specify with:
- “10 Tips for Boosting Open Rates”
- “5 Strategies to Double Your Revenue”
Personalize Your Subject Lines
Want to know the fastest, easiest way to increase your open rates? Personalize the subject line. Open rates increased by 50% when subject lines were personalized. Probably the easiest way to personalize an email subject line is to add your recipient’s name to the subject line (you can do that easily with marketing automation).
And you can further multiply results when combining personalization with trigger email campaigns, like sending a customer a happy birthday message or another specialized message. Trigger emails result in 197% higher open rates and 406% higher click-through rates.
Create Curiosity
Curiosity piques interest. Subject lines that create curiosity see 22% higher open rates. For example, consider a classic advertising headline from 1926:
“They Laughed When I Sat Down at the Piano — But When I Started to Play!”
This leaves readers wondering what happened next, compelling them to open the email.
But here’s the point. Brainstorm subject line ideas that leave your reader hanging so they can’t resist the urge to open and keep reading, allowing you to move them further along their buyer’s journey.
Use Stories to Engage Readers
Stories are memorable. It might be why people are 22 times more likely to remember information when it’s presented as a story versus a standalone fact.
An easy way to increase open rates is to mesh a story with an email subject line. The piano headline we just shared was a great example. But you could just as easily leverage a case study to tell a story. Here’s an example:
“How {Company} Lands $10.5M in New Deposits” (by the way, this is our case study, and you can read about it here).
Let’s say you sell marketing automation software. You could curate an interesting story about automation to write something like, “How this Company 4x Revenue With AI ….” Then, in the body of the email, weave together content that makes logical connections between the curated story and your brand messaging.
Even if you lack original stories, consider curating existing ones related to your industry.
Leverage AI for Creative Ideas
Hitting a creative wall writing email subject lines? Hey, you don’t have to go it alone. Many solutions are starting to leverage AI, which can get your creative juices flowing and help you write better subject lines.
For example, we just launched Act-On AI Create, which is an email content generation tool that helps with many tasks, including subject lines. Use it as a starting point for ideation and then refine and test email subject lines.
A/B Test and Refine Your Subject Lines
Experiment with proven strategies, but remember they’re only guidelines. Your results may vary. Overstock.com uses all-caps in their subject lines all the time because it’s a strategy that works for them. But they know what works because they’ve tested their subject lines, over and over, to determine what gets their audience’s attention.
Test your subject lines even if it’s a version A vs. version B experiment. If you want to step it up a notch, think about what questions you want to answer with testing. For example, do you want to know:
- What kind of personalization works better, using a first name or a company name?
- Does your audience respond well to numbers in subject lines?
- Do subject lines that tell a story get higher open rates with your audience?
And the list can go on. Outlining what you want to know helps shape the testing you will conduct and the analysis you do afterward.