Set custom preheader/preview text

An email’s preheader text (more accurately referred to as “preview text”) is the small block of text shown in an end-user’s email inbox, next to or underneath the subject line. It’s often used as a summary or an incentive to open and read the rest of the email.

Gmail Preview Text example

Normally, this preview is pulled from the first text in your email. This is OK if your content starts right away, and is short enough for a summary. However, if that isn’t the case, you might have text like ‘Is this email not displaying correctly?’ taking up valuable inbox real estate that could be used to incentivise opens instead!

In Customer.io, you can control exactly which text will appear in this preview for an email— to avoid situations like the above.

How to specify your preview text

Simple! In the composer, click on ‘Add preheader text’ next to the subject:

Adding preheader text

Save, and you’re good to go! You can also use Liquid here— customer attributes, event data (for event triggered campaigns), and so on.

Client support

Most email clients will display some kind of preview text. There’s variation in placement and length, but for most modern clients, you’re good to go. The below services do not support preview text:

Desktop Mobile Webmail
Lotus Notes 8.5 Blackberry GMX
Outlook 2003 Web.de
Outlook 2007 Freenet.de
Outlook 2010

If you want a more comprehensive guide to preview text support, check out this article from Litmus.

Preview text length

Whatever you write here, keep in mind that most mail clients will show between 35 and 75 characters!