The best way to write a subject line that gets opened
You worked hard on your email. The message is strong, the design looks great, and your offer is exactly what your audience needs. But if no one opens it, all that effort goes unseen.
Your subject line is the doorway to everything inside your email. It’s the first—and sometimes only—thing your reader sees before deciding whether to click or keep scrolling. And in a world where inboxes are constantly overflowing, that little line of text has to do a lot of heavy lifting.
The good news? Writing better subject lines doesn’t require being overly clever or sounding “salesy.” It’s about being useful, relevant, and human—the same way you’d talk to someone face-to-face about something that could help them.
Let’s break it down.
Why subject lines matter more than ever
Most people check their email on their phone—usually while doing something else. That means your audience isn’t reading carefully. They’re skimming.
You have about three seconds to catch their attention before they move on to the next thing. And even if they love your brand, you’re still competing with confirmation emails, invoices, calendar invites, and every other business vying for a slice of their attention.
Your subject line is your first impression, and in marketing, first impressions count.
The #1 mistake to avoid
Trying too hard to be clever.
Subject lines like “You won’t believe this…” or “Don’t miss out!!!” might feel catchy, but they often backfire. Not only do they sound like clickbait, but they can also land your email straight in the spam folder.
Your goal isn’t to trick people into opening; it’s to build trust. The most effective subject lines are clear, direct, and relevant.
People open emails when they instantly understand what’s inside and why it matters to them.
5 types of subject lines that actually get opened
These formats work across industries and are especially effective for small businesses trying to connect, not just convert.
1. The benefit-driven subject line
Focus on what your audience will gain.
- “How to plan a month of content in under an hour”
- “Save 10 hours this week with this one marketing shift”
Why it works: It’s clear, outcome-focused, and gives your reader an immediate reason to open.
2. The curiosity hook
Ask a question or tease something unexpected—without being misleading.
- “Struggling to stay consistent on Instagram?”
- “Most business owners miss this simple marketing step”
Why it works: It sparks curiosity while staying grounded in value.
3. The list or numbered subject line
Numbers signal structure and simplicity.
- “3 ways to improve your homepage today”
- “5 quick fixes for better product photos”
Why it works: Lists feel manageable and concrete, helping readers know exactly what to expect.
4. The personal subject line
Make it feel like a one-to-one conversation.
- “Can I be honest with you?”
- “I thought of you when I wrote this”
Why it works: It builds connection and trust—two things small businesses thrive on.
5. The timely subject line
Tie your message to the moment.
- “Last day to book your fall sessions”
- “This week only: free delivery on all orders”
Why it works: It creates urgency and encourages action without sounding pushy.
Quick tips to boost your open rates
Subject lines aren’t one-size-fits-all. Here are a few ways to make yours stronger:
- Keep it short. Aim for under 50 characters so it doesn’t get cut off on mobile.
- Use preview text wisely. This second line expands on your subject line—think of it as a “next sentence” that keeps curiosity going.
- Avoid spam triggers. Words like “FREE,” “ACT NOW,” or “LIMITED TIME” can send you to spam faster than you think.
- Test everything. A/B test your subject lines to see which style performs best. Sometimes a single word can double your open rate.
Let’s make it simple
If your emails aren’t getting opened, it’s not because your offer isn’t good—it’s because your subject line isn’t clear enough.
Start by focusing on clarity over cleverness. Ask yourself:
- What’s the main takeaway for my reader?
- Why does this email matter right now?
- Would I open this myself?
When your audience knows exactly what they’ll get—and why it’s worth their time—they’ll open, read, and engage.
And if you’re tired of guessing what to write each week, Navia can help. It learns your brand’s voice and writes subject lines that fit your audience, so every email feels like you wrote it yourself.
Because in today’s world, attention is limited, but your message deserves to be seen.
