Sonic 1/2 Price Cheeseburgers MondayYou’ll love the current Hot Deals, sorry you missed this deal. Cash in on your luck with 1/2 Price Cheeseburgers all day at Sonic on Monday, March 17. How do you like to personalize your Sonic Cheeseburger? Plus, don’t forget about 1/2 price drinks from 2-4 pm daily! Check with your local SONIC Drive-In for participation.