Your subject line is your first impression with your readers

—and it may be the difference between an opened email or one sent directly to the trash. If you have an e-commerce website, a newsletter, or a service-based business, applying tried and tested subject line formulas can make a huge impact to your email open rates.

Following are some of the best performing subject line templates to implement in your next email campaign:

1. The Curiosity Hook

Example: “You Won’t Believe What Happened After We Tried This Strategy”

Why it works: Curiosity compels individuals to click. It is a formula that hints at information without revealing it, and the reader opens the email to find out more.

2. The Question Format

Example: “Are You Making These Common SEO Mistakes?”

Why it works: A question personalizes the email. It engages the reader to think and be interested in the message, especially if the topic is one that speaks to them.

3. The List or Number Formula

Example: “5 Simple Steps to Increase Your Instagram Engagement”

Why it works: Numbers grab attention in a sea of cluttered inboxes. They also imply that the content is readable and consumable, something that is appealing to busy readers.

4. The “How-To” Subject Line

Example: “How to Get More Leads Without Spending a Dime”

Why it works: It is one of the most effective formats because it promises a solution. Individuals open these emails so that they can discover something useful.

5. The Personalized Subject Line

Example: “[First Name], Here’s a Special Offer Just for You”

Why it works: Personalization makes emails feel tailored. Including a first name or relevant detail can grab attention quickly.

6. The Scarcity/Urgency Technique

Example: “24 Hours Left to Claim Your Discount”

Why it works: People hate to miss out. If you make it time-restricted or time-sensitive, individuals will be more likely to act quickly.

Tips for Better Subject Lines:

• Shorten to under 50 characters.
• Avoid using spammy phrases like “free,” “buy now,” or “urgent.”
• Use emojis judiciously to inject a bit of personality.
• A/B test your subject lines (more on that below).

Final Thoughts

An effective subject line is no guarantee of success, but it primes your email for success. Try to mix these templates with your audience and content type. Keep testing and tweaking until you find what works best.