12 Proven Email Subject Line Formulas That Get Your Emails Opened
Ever sent an email campaign only to watch your open rates fall flat? You're not alone. As a copywriter I've learned that your subject line isn't just a first impression - it's your only chance to get that all-important click!
Why Most Subject Lines Fail
Let's be honest, most inboxes nowadays are battlefields. Your carefully crafted email is competing with hundreds of others. However, there is good news. I'm about to share my tried-and-tested formulas that consistently achieve 30%+ open rates.
The Psychology Behind High-Performing Subject Lines
Before we dive into formulas, let's understand what makes people ‘click’:
Curiosity (but not clickbait)
Personal relevance
Timeliness
Value proposition
Fear of missing out (used thoughtfully)
12 Subject Line Formulas That Work
1. The Curiosity Gap
Formula: [Intriguing Statement] + [Promise of Resolution]
Examples
This 'mistake' doubled our conversions...
The weird productivity hack our CEO swears by...
Why it works: It creates an information gap that can only be filled by opening the email
2. The Ultra-Specific
Formula: [Number] + [Specific Outcome] + [Timeframe]
Examples
3 Marketing Tweaks That Saved Us £1,000 last month
7 Morning Habits London CEOs Swear By
Why it works: It offers clear, measurable value and sets realistic expectations
3. The Question Hook
Formula: [Relevant Question] + [Hint at Solution]
Examples
Are your email open rates declining? Here's why
Struggling with work-life balance? This helped me
Why it works: Asking questions engages the brain and they prompt curiosity about the answer
4. The Social Proof Play
Formula: [Credible Number/Name] + [Desirable Outcome]
Examples
How 1,000+ UK Businesses Are Beating The Recession
What Marks & Spencer Learned About Customer Loyalty
Why it works: These leverage the power of social proof and credibility
5. The Time-Sensitive Motivator
Formula: [Timeframe] + [Benefit/Opportunity]
Examples
Only 24 hours left: Your marketing audit awaits
Quick update about tomorrow's price change
Why it works: These create a sense of urgency without feeling pushy
6. The Personal Touch
Formula: [Personal Element] + [Valuable Insight]
Examples
James, I noticed something about your website
My biggest marketing mistake (and what I learned)
Why it works: Feels like a one-to-one conversation rather than a mass email
7. The How-To Hook
Formula: How to [Achieve Desired Outcome] without [Common Pain Point]
Examples
How To Increase Sales Without Spending More on Ads
How To Write Better Emails Without Hiring A Copywriter
Why it works: These promise a solution while acknowledging common challenges
8. The List Appeal
Formula: [Number] + [Desirable Things] + [Benefit]
Examples
5 simple tweaks that boosted our email opens
8 subject line mistakes most marketers make
Why it works: These set clear expectations and promises organised, digestible content
9. The Insider Edge
Formula: [Exclusive Info] + [Benefit]
Examples
Behind the scenes ~ Our content strategy revealed
Internal memo ~ Changes coming to Instagram
Why it works: Makes readers feel like they're getting special/privileged information
10. The Problem Solver
Formula: [Common Problem] + [Hint at Solution]
Examples
Tired of Low Conversion Rates? Try This
Your Unsubscribe Rate Might Be Telling You Something
Why it works: Directly addresses the pain points your audience experiences
11. The Direct Approach
Formula: [Clear Value Proposition]
Examples
Your October marketing checklist is ready
New case study: How we doubled email engagement
Why it works: Sometimes simply, clarity beats cleverness
12. The Pattern Interrupt
Formula: [Unexpected Statement] + [Relevant Tie-in]
Examples:
This email won't make you millions...
Don't buy our new course (until you read this)
Why it works: By breaking expected patterns your subject line stands out
Testing Your Subject Lines
Remember, what works for one audience might not be so successful with another. So, always:
Test different formulas
Track open rates by your market segment
Note which formulas work best for specific types of content
Consider your posting timing and context
The Golden Rules of Subject Lines
Keep it under 50 characters when possible
Avoid spam trigger words
Write for your specific audience
Test on mobile devices
Always, always deliver on your subject line's promise
Next Steps
Choose three formulas from above that resonate with your brand voice and start testing them in your next email campaign. Remember to track your results and then adjust accordingly.
Need help crafting the perfect subject line? Contact us if you want to chat about your email marketing strategy.