How a Single Underline Boosted Response by 47 Percent

In this episode of The Copywriting Podcast with Fexingo, Lucas and Luna explore the surprising power of underlining in direct mail copy. They break down a classic test from the 1970s where a single underline under the key benefit in a sales letter lifted response by 47 percent. Lucas explains the psychological mechanism: underlines act as visual anchors, forcing the eye to linger on the most persuasive element. Luna connects it to modern web copy, where bold and italics can similarly boost conversions. They discuss how to use underlines without overdoing it, and why this simple formatting trick still works in the age of short attention spans. No jargon, no theory — just a practical lesson you can apply to your next email or landing page. #Copywriting #DirectMail #Underline #ConversionRate #Persuasion #Marketing #Headline #SalesLetter #ResponseRate #VisualAnchors #CopyHack #Test #Retail #MailOrder #Psychology #FexingoBusiness #BusinessPodcast #MarketingTips Keep every episode free: buymeacoffee.com/fexingo