1/2 price drinks and slushes all the time when you order (and pay) ahead in the Sonic app. Happy Hour at Sonic is 2-4 PM (not 2-5PM). According to various sources online, they also have 99 cent snacks during that time. https://www.sonicdrivein.com/app
If you have the Sonic app you can order drinks anytime and they are half off.
They are 1/2 price from 2-5
There is a reduced time called Happy Hour from 2-5pm. Not sure how much cheaper they are however.
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