Preheader text is the snippet shown next to or under the subject line. Learn how to write preheaders that increase opens and reduce confusion.
Preheader text is the short line many inboxes show next to the subject line in the message list. It acts like a second headline and often determines whether the email feels worth opening.
Good preheaders complement the subject rather than repeating it. They add context, clarify value, or reduce uncertainty with specifics like time, benefit, or next step.
To optimize preheaders, keep them concise, avoid filler like “view in browser,” and test variations. Preheaders are especially important on mobile, where the inbox preview is short and competitive.