A preheader is the very first text that appears in an email, at the very top. In most email programmes, this text shows up as a third line underneath the sender information and subject line. For that reason, it’s important to take advantage of your preheader and write something that really grabs people’s attention.
Sometimes you’ll see emails with “Web version” or “Click here if your email looks strange” in the preheader, but that’s a waste of this important space. Instead, write a short introductory text that describes your content and will encourage the recipient to read on, preferably by complementing the subject line.
NOTE: If you’re making a template, it’s a good idea to write a preheader that can work with all your emails, in case later on the editor forgets to change the text in their email.