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Email Preheader Defined

The email preheader is the short snippet of text that appears next to an email’s subject line in a user’s inbox. The preheader is intended to provide a brief preview or summary of the email content to give the recipient more context before opening the message. For email marketers, preheaders provide a valuable opportunity to enhance an email's subject line and entice recipients to open the message.

Although writing a preheader is not required to send an email, doing so is considered best practice for commercial email and typically increases email open and engagement rates.

Explore the OneSignal Email Performance Guide to check out some examples of good preheaders, poor preheaders, and more email optimizations for higher-performing emails.

How to Use it in a Sentence

Writing a captivating email preheader can help you improve email open rates.

Common FAQs

There are some basic principles to consider when writing a preheader. Learn 10 tips for writing good email subject lines and preheaders

The maximum character count for preheaders is typically 250 characters, be we recommend being more precise whenever possible. Remember that the first five or so words of your preheader are what your recipient sees first — make sure that you use this message real-estate to your advantage.

A subject line serves as the message title in that it is the first content you see when a message arrives in your inbox. A subject line is typically in bold text to make it stand out from the preheader. A preheader is the text that follows the subject line. Preheaders are typically longer and provide more context to enhance and inform the subject line.