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Writing Effective Email Subject Lines

Last Updated: Jul 29, 2025

Your subject line determines whether people open your email or delete it. 47% of recipients decide to open emails based on the subject line alone, so getting this right is crucial for your campaign success.

Key Best Practice

1. Keep It Short

  • Aim for 30-50 characters – Longer lines get cut off on mobile devices, and 55% of emails are opened on phones.
  • Good: “Flash sale: 40% off today”
    Too long: “Don’t miss our incredible limited-time flash sale event”

2. Be Clear and Specific

Tell people exactly what’s inside your email.

Examples:

  • Instead of “Great deals” → “25% off running shoes”
  • Instead of “Important update” → “Your order ships tomorrow”
  • Instead of “You’ll love this” → “New recipe: 15-minute pasta”

3. Create Honest Curiosity

  • Spark interest without misleading people about your content.
  • Good: “The mistake 90% of runners make”
    Bad: “You won’t believe what happened next!”

4. Use Smart Personalization

72% of people prefer personalized subject lines, but don’t overdo it.

Examples:

  • “Sarah, your cart is waiting”
  • “New arrivals in Austin”
  • “Based on your last purchase…”

5. Add Real Urgency

Time-sensitive language can boost opens by 22%, but only when it’s genuine.

  • Works: “Sale ends at midnight” which actually ends at midnight
    Doesn’t work: “Limited time offer!” that never actually expires

6. Include Numbers

Numbers grab attention and set clear expectations.

Examples:

  • “5 ways to save money”
  • “10% off your order”
  • “3 new features”

What To Avoid

  • ALL CAPS – Looks like spam
  • Too many !!! – More than 2-3 punctuation marks
  • Misleading content – Don’t promise what you can’t deliver
  • Generic words – “Newsletter,” “Update,” “Amazing deal”

Quick Examples of Subject Lines

E-commerce

  • “Your cart misses you”
  • “Back in stock: That item you wanted”
  • “25% off ends tonight”

Business

  • “Your trial expires in 3 days”
  • “New feature: One-click exports”
  • “How we increased leads by 40%”

Content

  • “The productivity hack nobody talks about”
  • “5-minute read: Remote work changes”
  • “This week’s most-shared article”

The Bottom Line

Great subject lines are clear, honest, and focused on what the reader cares about. Create just enough curiosity to get the click while accurately representing what’s inside.

 

Don’t be clever at the expense of clarity. Test different approaches with your audience and use what actually works for your subscribers.

That’s It!

If you got stuck on a specific task or can’t find a way to execute a particular job, contact our support team via LiveChat or [email protected] – we’re here to help 24/7.

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