TCBY (The Country's Best Yogurt, formerly This Can't Be Yogurt) is an international franchise chain of frozen yogurt stores based in the United States. It is the largest U.S. retailer of soft-serve frozen yogurt with live active cultures.

In 1981, the first TCBY store was opened in Little Rock, Arkansas, USA by Frank D. Hickingbotham. TCBY began franchising the next year, and by 1984 there were over 100 stores. As the company grew, the name was applied for a time to the tallest building in Arkansas, known until 2004 as the TCBY Tower, in downtown Little Rock. It is now known as Metropolitan Tower.

Prior to 1984, the company's name was "This Can't Be Yogurt", but a lawsuit from a competitor named "I Can't Believe It's Yogurt!" forced TCBY to create a new name from its initials.

In 2000, TCBY was acquired by Mrs. Fields Famous Brands.

In the summer of 2010, the company opened a prototype store in Salt Lake City, Utah operating under a different business model. Instead of customers ordering and being served in a traditional fashion, they serve themselves using any combination of available yogurt flavors, add their own mix of fruit or candy toppings, and pay by the ounce. The store sports a different logo to match the store's ultramodern, European styling. Numerous stores have since opened across the United States.