Email Preview Text: How to Write a Preheader That Adds Something

The second line in the inbox

Before anyone opens your email they see three things: who sent it, the subject and a short line of preview text. That last line is also called the preheader. Most platforms let you write it; if you do not, the inbox fills it with whatever the email starts with, which is often a view in browser link or the alt text of your logo.

The preview text generator writes several options from your subject line and checks each one. This guide explains what makes a good one.

Where inboxes cut it off

There is no single length. The cut depends on the app, the screen width, the font size and how long your subject is. Some general patterns hold:

• Phone inbox lists show the start of the preview under the subject. The first few words carry the point.
• Desktop inbox lists often put the preview on the same line as the subject, so a long subject leaves less room.
• Lock screen notifications may show only a few words of preview, or none at all, so the subject has to work alone.

The practical rule: put the most useful words first and treat everything after them as a bonus.

Six angles to try

• Add the detail. The size of the offer and when it ends, if the subject did not say.
• State the deadline. Only when it is real.
• Name a benefit. What the reader gets from opening.
• Raise curiosity. Hint at something inside without being cryptic.
• Say it plainly. A straight summary works well for readers who trust you.
• Ask a question. One the email then answers.

The mistake that wastes it

Repeating the subject. If the subject says the sale starts now and the preview says the sale starts now, the reader has learned nothing new from the second line. Treat the pair as one message split across two lines: the subject earns attention and the preview gives the reason to act.

The other common miss is leaving it blank. An empty preview is not neutral; it becomes whatever technical text the email happens to begin with.

Testing the pair

Read subject and preview together on your own phone before sending. Send a test to yourself and look at it in the inbox list, not just the opened email. For a checklist of both lines, paste them into the subject line tester. Over time, compare the opens your own email platform reports for different styles; nothing else tells you what works for your list.

Next step

Paste your subject into the preview text generator, pick the kind of email and add your offer and deadline if you have them. Choose the option that adds the most and edit it into your own words. If you are writing a new welcome series, the welcome email sequence generator outlines the emails around it.

A preview line needs a list to land in. Nudgesmart builds the signup popup that grows that list, starting from ready-made templates.