Let’s face it, your email could have the juiciest content in the world, but if no one opens it, it might as well not exist. And that’s where the subject line comes in. It’s the first thing people see in their inbox, and in many cases, the only thing they see. So, getting it right? Kinda important.
The truth is, most of us don’t have time to overthink every single email we send. But that doesn’t mean you have to guess. Some tried-and-true subject line formulas consistently get clicks. And the best part? You don’t have to be a professional copywriter to use them.
In this post, we’ll walk through seven subject line formulas that work, plain and simple. No fluff. No hype. Just straightforward tools you can use to get more eyes on your emails.
1. Spark Curiosity Without Giving It All Away
Ever get an email and think, “Wait, what does that mean?” And then click because you have to know?
That’s the curiosity formula in action. These subject lines tease just enough to make people want more. It’s like a movie trailer that shows you a flash of something exciting but leaves out the ending.
The trick here is to give your reader a taste, a hint of what’s inside, without spilling the full story. Use phrases that make people lean in, mentally. Ask questions, leave things open-ended, or use unexpected words that stand out in a crowded inbox.
Be careful: if you build curiosity, you’d better deliver in the email. Nothing kills trust faster than a clickbait subject line with a boring follow-up.
2. Use Numbers to Create a List They Can’t Resist
There’s something oddly satisfying about numbers in subject lines. They signal order, clarity, and something easy to skim. And in the world of flooded inboxes, that’s a win.
When you include a number, you’re setting a clear expectation. Readers know they’re getting a quick, digestible list, not a novel. Think about all the times you’ve clicked on a listicle during your lunch break. That same logic applies here.
Keep it simple. Odd numbers tend to perform better. Why? Who knows. It may feel more human. Either way, list-style subject lines are a go-to for a reason: they work.
3. Ask a Question Your Reader Can’t Ignore
Ever been asked a question and your brain automatically tried to answer it? That’s the power of this formula.
When you ask a question in a subject line, it pulls your reader in by making them part of the conversation.
It feels personal, even if you’re emailing a list of thousands.
The key is to ask something that taps into a pain point, a curiosity, or a goal your reader already has. Make them pause and think, “Hmm… do I? Should I? What if I did?”
If you know your audience well, this type of subject line can feel like you’re reading their mind. And that kind of connection? It’s pure gold.
4. Give ‘Em a Clear “How-To”
Let’s be honest: sometimes we just want someone to tell us how to do something without all the fluff. That’s where the how-to formula comes in.
These subject lines promise a clear takeaway. They tell the reader, “Open this email and you’ll learn how to [fill in the blank].” It’s actionable, straightforward, and incredibly effective.
People are busy. They don’t want vague promises. They want to know what they’re getting and why it matters. So if your email offers a useful process, hack, or tip, say it. Loud and clear.
Pro tip: keep it relevant to everyday life. The more practical and doable your “how-to” sounds, the better.
5. Add a Little Urgency
Ever feel a slight panic when you see a subject line like “Last chance” or “Ending today”?
That’s the urgency formula doing its job. It taps into FOMO, fear of missing out, and it works like a charm when used sparingly.
The key here is not to overdo it. If every email you send says something is “urgent,” it won’t be long before no one believes you.
Use urgency when there is a deadline or a time-sensitive update. Maybe something ends at midnight, or it’s a limited-time resource. When people know the clock is ticking, they’re more likely to act now rather than later (or never).
6. Lead with the Benefit
What’s in it for me?
That’s the question your readers are asking, whether they realize it or not. So answer it right in the subject line.
This formula is all about clarity. Instead of being clever or mysterious, you’re saying, “Here’s exactly what you’ll get if you open this.” Think of it like putting the reward front and center.
It’s great for value-packed content, like guides, insights, or helpful tools. And if you know what your audience wants, you can speak directly to that desire.
No need to bury the lead. Sometimes, direct is the most effective approach.
7. Make It Feel Personal
Ever get an email that felt like it was written just for you? That’s the magic of personalization.
NoPersonalization can also mean referencing location, behavior, or interests, anything that makes the reader feel like you see them.
It creates a one-on-one vibe, even if it’s a mass email. And when people feel like something is meant for them, they’re way more likely to open it.
Of course, this works best when you’ve got good data. But even without deep personalization tools, you can write like you’re talking to one person. That alone goes a long way.
Wrapping It Up
Crafting the perfect subject line isn’t about being a genius wordsmith. It’s about understanding what makes people click. Whether you’re sending a newsletter, a product update, or a simple announcement, these seven formulas give you a toolkit to work with.
Try them. Mix them. Adapt them to your voice. You don’t have to reinvent the wheel every time.
And remember, if your open rates have been looking a little sad lately, your subject line might be the first thing to fix.
Ready to test one of these out? Go for it. Your next great subject line could be just a few words away.
We’re not just talking about adding someone’s name (although that helps).
