Preheader Text
Preheader text is the short summary text that appears next to or below the subject line in an email inbox preview.
What Is Preheader Text?
Preheader text (also called preview text) is your second chance to convince someone to open your email. In most email clients, it appears immediately after the subject line in the inbox list view, providing additional context. The ideal preheader length is 40-130 characters, though this varies by email client and device. If you don't set a preheader explicitly, email clients will pull the first text from your email body — which is often a navigation link, an unsubscribe notice, or 'View in browser', none of which are compelling reasons to open.
Why It Matters for Newsletters
Preheader text can boost open rates by 5-15% when used effectively. It works in tandem with your subject line — the subject line catches attention, and the preheader reinforces the reason to open. Leaving it blank or defaulting to boilerplate text wastes valuable inbox real estate.
Best Practices
- Always set explicit preheader text — never let it default to email body content
- Complement the subject line rather than repeating it
- Include a hook or value proposition that the subject line didn't cover
- Keep it between 40-100 characters for consistent display across clients
- A/B test preheader text alongside subject lines for maximum impact
How Aldus Handles This
Aldus automatically generates optimised preheader text for every newsletter issue, complementing the AI-crafted subject line. The preheader provides additional context that increases open rates without any extra effort.