# Write effective preheaders

> The preview text after your subject line is prime inbox real estate - here is how to use it well.

Source: https://www.kualo.com/knowledgebase/mailmachine-campaigns/write-effective-preheaders
Updated: 2026-06-10

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A preheader - or preview text - is the short snippet that appears after your subject line in inboxes like Gmail and Outlook. It's one of the first things a recipient sees, so it's a real influence on whether they open your email. This guide covers writing a good one.

## Add a preheader

1. Open the email designer.
2. Click **Settings** on the right, and find **Metadata**, then email details.
3. Type your preheader. If your content's ready, click the **magic wand** to generate ideas with AI - reload for more, and pick a tone (see **[Create email preheaders with AI](/knowledgebase/mailmachine-campaigns/create-email-preheaders-with-ai)**).
4. Save the one you want.

## What makes a good preheader

- **Keep it short** - aim for 35-90 characters so it isn't cut off.
- **Complement the subject line** - expand on it, don't repeat it.
- **Spark curiosity or urgency** - give a reason to open.
- **Use active language** - verbs that invite a click.
- **Put the important part first** - in case it's truncated.

## Examples

- **Subject:** "New products just arrived!" - **Preheader:** "Shop the latest collection before it sells out"
- **Subject:** "Your cart is waiting" - **Preheader:** "Complete your purchase and save 15%"
- **Subject:** "Weekly newsletter" - **Preheader:** "Industry insights, tips and exclusive offers inside"

## Troubleshooting

**Preheader too long** - keep it under about 90 characters, lead with the key information, and check where different clients truncate.

**Email-client quirks** - some older clients don't support preheaders, and Gmail may pull in extra text if yours is very short. Test across the major clients before sending.

A strong preheader works hand in hand with a strong subject line and lifts your **[open rates](/knowledgebase/mailmachine-reporting/understand-open-rates)**. Need a hand? [Open a support ticket](/knowledgebase/getting-started/how-to-create-a-support-ticket-in-mykualo).

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_Source: Kualo Knowledgebase — https://www.kualo.com/knowledgebase/mailmachine-campaigns/write-effective-preheaders · © Kualo Ltd._