Email subject lines: 10 top tips for success

In an inbox brimming with emails demanding your readers’ attention, the subject line is your first, and sometimes your only, chance to make an impression. In our experience managing email campaigns, strong subject lines consistently outperform body content in driving engagement. So whether you are sending a marketing email, a newsletter, or a one-to-one message, the subject line can determine whether your email gets opened or ignored in today’s ever-crowded inboxes.

Why Subject Lines Matter 

The subject line acts as a gateway to your content. No matter how valuable or well-written your email is, it will not deliver results if it is never opened. A strong subject line can: 

• Boost open rates and engagement 

• Set expectations for the reader 

• Build trust and credibility 

• Encourage action or clicks 

On the flip side, a weak or misleading subject line can lead to low engagement, or worse, unsubscribes. 

10 Top Tips for Subject Line Success 

The following are subject line best practice tip to help you improve your email open rates.  

1. Keep it short and clear 

Aim for 6–10 words or under 50 characters to ensure visibility across devices. Many emails are opened on mobile devices, where long subject lines get cut off. 

2. Make it relevant 

Your subject line should match the content of your email. Misleading readers might get you an open, but it damages trust long term. 

3. Create a sense of urgency 

Phrases like “Last chance” or “Ending today” can encourage readers to act quickly but use them sparingly to avoid fatigue. 

4. Personalise where possible 

Including a name or relevant detail can make your email feel more tailored and engaging. 

5. Ask a question 

Questions spark curiosity and invite the reader to engage. For example: “Are you making this common mistake?” 

6. Use action-oriented language 

Start with verbs that inspire action, like “Discover,” “Learn,” “Boost,” or “Save.” 

7. Spark curiosity 

Give just enough information to intrigue the reader without revealing everything. This encourages clicks. 

8. Avoid spam triggers 

Overusing ALL CAPS, excessive punctuation (!!!), or words like “FREE” can send your email straight to spam folders. 

9. Test and optimise 

Run A/B tests on different subject lines to see what resonates best with your audience. Learn how to set up A/B split test campaigns in e-shot to continuously improve performance. 

10. Align with your brand voice 

Your subject line should reflect your tone, whether that is professional, friendly, or playful, so it feels consistent and authentic. 

Bonus Tip: Using Emojis Wisely 😉  

Emojis can help your subject line stand out in a busy inbox and add personality to your message. When used strategically, emojis can increase visibility and even boost open rates. However, moderation is key: 

• Use emojis that match your message and audience 

• Avoid overusing them, one is usually enough 

• Make sure they render correctly across devices 

• Do not rely on them to replace clear wording 

A well-placed emoji can enhance your subject line, but it should complement your message, not distract from it. 

Subject line examples 

Here are some proven subject line examples you can take for inspiration, categorised by intent: 

Curiosity-driven: 

• “You’re missing out on this…” 

• “This one mistake is costing you” 

• “We didn’t expect this result…” 

Urgency-focused: 

• “Last chance to save 20%” 

• “Ends tonight: Don’t miss out” 

• “Final call before it’s gone” 

Personalised: 

• “John, this is just for you” 

• “A quick idea for your business” 

• “We picked this for you” 

Benefit-led: 

• “Boost your productivity in 10 minutes” 

• “Get better results with less effort” 

• “Save time with this simple trick” 

Question-based: 

• “Are you making this common mistake?” 

• “Want better email results?” 

• “Ready to grow your audience?” 

What makes an effective email subject line? 

An effective email subject line is short, relevant, and aligned with the email content. Subject lines under 50 characters are more likely to display fully on mobile devices and achieve higher open rates. 

High‑performing subject lines clearly signal value, use action‑oriented language, and avoid misleading claims. Personalisation and urgency can improve engagement when used accurately and sparingly. 

Consistent testing is essential. Regular A/B testing helps identify which wording, tone, and structure resonate most with your audience while maintaining deliverability and trust. 

Final Thoughts 

A great subject line is both an art and a science. It requires creativity, clarity, and continuous testing. By applying these tips, you’ll improve your chances of standing out in those crowded inboxes and drive better results from your emails. 

Remember: if your subject line doesn’t capture attention, the rest of your message may never be seen. 

Last Updated: May 2026