Short preheader text automatically populates in email campaigns if it is too short. Preheader text is essential for every email, and email systems rely on it to display a preview in the inbox. You must set a preheader text greater than 30 characters long. This is because preheader text is inevitable for any type of email. If you do not set a custom preheader or provide one too short to meet the 30-character minimum, email systems will start populating the preheader with email content. To avoid that happening, you should always set a preheader of at least 30 characters. For mobile devices, aim closer to the 55-character maximum. This ensures your preheader displays fully and gives recipients a clear idea of your email content. Properly set preheaders improve engagement, make emails look professional, and prevent email systems from populating them automatically.
By following these guidelines, you can prevent the issue where short preheader text automatically populates and maintain full control over your email campaign previews.