McDonald's reportedly plans to close all five of its CosMc's test locations this summer, just 18 months after opening the five the beverage-focused stores.

The closures come amid McDonald's confirmation that it would be testing its CosMc's beverages on its regular menu, as was previously reported earlier this month.

"Building on the insights gained from the pilot standalone locations, CosMc’s-inspired flavors will be landing at McDonald’s as part of the upcoming US beverage test, seamlessly blending out of this world tastes into the McDonald's experience. With our new dedicated category team focused on beverages, we know we can bring more delicious and innovative drinks to more fans.," McDonald's said in a news release shared last week. "What started as a belief that McDonald’s had the right to win in the fast-growing beverage space quickly came to life as a multi-location, small format, beverage-focused concept. It allowed us to test new, bold flavors and different technologies and processes – without impacting the existing McDonald’s experience for customers and crew.

"We cannot wait to share more about our beverage developments and tests in the future," the company added. "Stay tuned as we continue to explore new horizons and bring fresh, exciting flavors to our fans!"

McDonald's CEO Chris Kempczinski previously said the company gained "interesting leanings" from its rollout of the concept restaurant in Illinois in late 2023 and the company plans to work with individual franchisees to test some of CosMc's exclusive beverages on standard menus.

“It’s part of why we set up beverages as one of our key three category structures — just because of the opportunity that we saw there,” Kempczinski said, though not sharing additional details on the menu expansion beyond McDonald's being "committed to going after beverages."

McDonald's didn't specify which beverages would be included, but the popular Instagram food account @snackbetch speculated that Sprite Moonsplash, Popping Pear Slush, Tropical Spiceade, Blueberry Ginger Boost, Iced Churro Latte, Iced French Toast Galaxy Latte, Churro Cold Brew Frappe and Chai Frappe Burst would be among the options considered.

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