Sonic is offering half-price shakes on Mondays!

Sonic is offering half-price shakes on Mondays! This promotion runs through December 16, 2024, at participating locations. Each Classic Shake and Master Shake is half price, excluding the Red Velvet Cake Batter Shake. Please note that tax and add-ins are extra. The discount will automatically apply in the app, online, and at the drive-in. This offer is not valid with combos, delivery, or any other promotions.