After the subject line, recipients see one more piece of information before deciding whether to open: the preview text (also called the preheader). This week we cover this underutilized conversion opportunity.
This Week’s Lesson
Preview text is the snippet of text shown below or beside the subject line in the inbox preview. It can be explicitly set in your email, or inbox providers will extract the first visible text from your email body.
When you don't set preview text, inbox providers pull whatever text comes first in your email. This is often 'View this email in your browser,' 'Unsubscribe,' or an ALT text string from an image — none of which help you get opened.
Best practice preview text: extends and complements the subject line rather than repeating it. Subject: 'Week 28: Preview Text' — Preview: 'The second line you're probably wasting — and how to fix it today.' Together they tell a compelling story that neither could alone.
Preview text length: aim for 90-140 characters. Mobile shows roughly 35-90 characters. Desktop clients show more. Front-load the key message in the first 40 characters.
Hidden preheader technique: many email templates include preview text in a tiny (1px, white text on white background) element at the very top of the email HTML. This lets you control the preview text independently of the visible email body.
A/B testing preview text is underrated. In our testing, optimized preview text lifts open rates by 7-12% above optimized subject lines alone — often with no change to the subject line at all.