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A hand holds a clear plastic cup filled with a dark, carbonated beverage. The cup has the SONIC logo on it, and condensation is visible on the outside of the cup. The background shows part of a car window.
Ivan B. / Yelp

The dirty soda trend, where lots of flavorful mix-ins are added to soft drinks to make a sort of mocktail, is still going strong. Sonic, a chain that’s always been known for its endlessly customizable drinks, is highlighting some of its dirty Cokes by giving them out for free. 

This isn’t even one of those piddly “oh, you get one free small soda on this one day when you also buy $20 of burgers and give us your second born child” kinds of deals, either. Here are all the details so that you can get your free dirty soda from Sonic.

What Is Sonic Giving Away?

Three tall Sonic drinks filled with ice are shown: one with lemon slices, one with creamy topping, and one with red candy pieces, all in clear cups with blue straws against a blue background.
Sonic Drive-In

Sonic is giving away free Coca-Cola, Diet Coke, or Coke Zero drinks. You can add as many customizations to them as you like for free, and you can get any size, including the big old 44-ouncers. 

Unlike most fast-food freebies, you can get these dirty Cokes once a day, every day, from now through December 28th. That’s six weeks of free sodas, and it’s unlikely to get boring considering all the add-ins and mix-ins you can get.

How Do I Get One?

A hand holding a smartphone displaying the SONIC Drive-In app page in the App Store, with a wooden table background.
Blakelee Bartik / Cheapism

In order to get your free dirty Cokes, register for a Sonic account because you’ll need to order online or in the chain’s app to get them. Then — and here’s the catch, because there’s always a catch — you’ll have to make a purchase to get your free Coke.

Thankfully, you can make “any” purchase, which means it’s time to find the cheapest item possible to buy. If you’re hungry, that’s easy; just choose something cheap from the $2 menu like a junior double cheeseburger or a Crispy Tender Wrap. If you’re not, you can always see if you can do something sneaky, like buy a packet of sauce or something. Or, get a plain vanilla soft serve and make your own Coke float.

What Can I Customize It With?

A close-up of a styrofoam cup filled with crushed ice and a dark soda, with a red straw inserted. Part of a hot dog with melted cheese is visible in the lower left corner.
©Tripadvisor

Customizing your free Coke is the fun part (and where you’re getting the best value). Sonic has about 15 flavored syrup add-ins, plus fruit, sugar-free add-ins, and even candy. Most cost 69 cents to $1.49, so they can really add up under normal circumstances.

Have you ever wanted a mango flavored Coke Zero with real strawberries? Done. A coconut Coke with cream and vanilla? That one sounds great to us. Want to chew your soda with Nerds candy and blue raspberry flavor bubbles? You got it. 

If you have decision paralysis from all the choices, there are three options that Sonic has suggested to help. 

  • Coke with strawberries and cream
  • Coke with blood orange flavor and vanilla 
  • Coke with cherry flavor and pickles (yes, PICKLES)

Sonic went a little down the state fair food path with those pickles, but we’ll try anything once. As we all know, free is the best flavor.

More Sonic stories:

Sonic Rainbow Slush
u/BabyH1ppo via Reddit.com

Meet the Writer

Lacey Muszynski is a staff writer at Cheapism covering food, travel, and more. She has over 15 years of writing and editing experience, and her restaurant reviews and recipes have previously appeared in Serious Eats, Thrillist, and countless publications in her home state of Wisconsin.