Email Preheader Optimization refers to refining the short preview text that appears alongside or below the subject line in an email inbox. This snippet gives recipients additional context about the email?s content, influencing open rates and engagement. Marketers strategically craft preheaders to complement subject lines, create curiosity, and boost readability on mobile devices. A/B testing different preheader text variations can help identify which messages drive the highest engagement. Email marketing platforms like Mailchimp and ActiveCampaign provide tools for preheader customization. Well-optimized preheaders can significantly increase email open rates and overall campaign effectiveness.