What is Subject Line?
TL;DR
The text recipients see before deciding whether to open your email, arguably the most important element of any email campaign. A compelling subject line in a crowded inbox is the difference between engagement and deletion. Effective subject lines: create curiosity, promise specific benefits, use urgency appropriately (not deceptively), and match the email content. Keep them under 50 characters for mobile visibility. Test subject lines through A/B testing, small changes can swing Open Rates by 10-20%. Avoid spam triggers: ALL CAPS, excessive punctuation!!!, "free" or "act now" without context. Personalization (name, company, location) can improve performance but isn't magic. Preview text (the secondary line after the subject) extends your pitch, don't waste it with "View in browser." Subject lines are promises; your email content must deliver.
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Frequently Asked Questions About Subject Line
How long should email subject lines be?
Under 50 characters for mobile visibility. Many recipients see only the first 30-40 characters. Front-load the most important words. Test shorter subjects, they often outperform longer ones.
What makes a subject line compelling?
Curiosity, specific benefits, appropriate urgency, and matching content. 'Your order shipped' is clear and relevant. '5 mistakes killing your SEO' creates curiosity. 'Last chance: sale ends tonight' adds urgency.
Should I use personalization in subject lines?
It can help but isn't magic. 'Sarah, your exclusive offer' may outperform generic subjects. Test it, some audiences respond well, others find it gimmicky. Don't rely on personalization to save weak subjects.
What subject line practices hurt deliverability?
ALL CAPS, excessive punctuation!!!, 'FREE' in isolation, 'Act now,' and false urgency. These trigger spam filters. Be honest and direct. Promise what your email delivers.
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