Email Marketing Term
What is Subject Line?
The text that appears in the recipient's inbox describing the email's content or purpose.
The subject line is the most critical element determining whether your email gets opened. It's the first (and sometimes only) impression you make.
Effective subject lines are typically 40-60 characters to avoid truncation on mobile devices. They should create curiosity, convey value, or trigger urgency without being spammy.
Subject lines directly impact open rates, which cascade to affect click-through rates, conversions, and ROI. A 10% improvement in open rate can significantly boost campaign performance.
Examples
- Good: "{FirstName}, your order ships tomorrow"
- Good: "50% off ends at midnight"
- Bad: "FREE!!! CLICK HERE NOW!!!"
Tips for Subject Line
- ✓Keep subject lines under 50 characters for mobile
- ✓Use personalization tokens when possible
- ✓A/B test subject lines on every campaign
- ✓Avoid spam trigger words like FREE, URGENT, WINNER
Related Terms
Open Rate
The percentage of email recipients who open a specific email campaign.
Preheader Text
The preview text that appears after the subject line in email clients, providing additional context.
Email Personalization
Customizing email content based on recipient data like name, behavior, or preferences.
A/B Testing
Comparing two versions of an email element to determine which performs better.
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