Sonic: Half Price Breakfast Burritos (September 3rd) 08/31/2013 By MFA Leave a Comment This post may contain affiliate links, please see my disclosure policy. Stop by Sonic on September 3rd and get a half price breakfast burrito. The promotion runs all day so plenty of time to make a trip. And just FYI- egg whites are now available! You can find a Sonic location near you here.