Krystal is an American regional fast food restaurant chain headquartered in Dunwoody, Georgia, with restaurants in the Southeastern United States and Puerto Rico. It is known for its small, square hamburgers, called sliders in places other than the Southeast, with steamed-in onions. Krystal moved its headquarters from Chattanooga, Tennessee, where it had been based since 1932, to the Atlanta suburb of Dunwoody in early 2013.

Taco Bell Corporation is an American multinational chain of fast food restaurants founded in 1962 by Glen Bell (1923–2010) in Downey, California. Taco Bell is a subsidiary of Yum! Brands, Inc. The restaurants serve a variety of Mexican-inspired foods, including tacos, burritos, quesadillas, nachos, novelty, and specialty items, and a variety of "value menu" items. As of 2023, Taco Bell serves over two billion customers each year, at 8,212 restaurants, more than 94 percent of which are owned and operated by independent franchisees and licensees.

Sonic Corporation, founded as Sonic Drive-In and more commonly known as Sonic, is an American drive-in fast-food chain owned by Inspire Brands, the parent company of Arby's, Jimmy John's, Buffalo Wild Wings, Baskin-Robbins, and Dunkin'. Sonic, founded by Troy N. Smith Sr., opened its first location in 1953, under the name Top Hat Drive-In. Originally a walk-up root beer stand outside a log-cabin steakhouse selling soda, hamburgers, and hot dogs, Sonic currently has over 3,400 locations in the United States.

Zaxbys is an American chain of fast casual restaurants offering chicken fingers, sandwiches, chicken wings, appetizers, and salads. The chain operates primarily in the Southern United States and has more than 900 locations. Most Zaxbys restaurants are owned and operated through franchising.

Hardee's Restaurants LLC is an American fast-food restaurant chain operated by CKE Restaurants Holdings, Inc. ("CKE") with locations primarily in the Southern and Midwestern United States. The company has evolved through several corporate ownerships since its establishment in 1960 in North Carolina.

Arby's Restaurant Group, Inc. doing business as Arby's is an American fast food sandwich restaurant chain with more than 3,300 restaurants. The flagship property of Inspire Brands, it ranked third in systemwide sales in the United States in the quick-service and fast-casual restaurant industries in 2012, behind Subway and Panera Bread. In October 2017, Food & Wine called Arby's "America's second largest sandwich chain ".

Burger King Corporation is an American fast food chain of hamburger fast food restaurants, headquartered in Miami-Dade County, Florida. The company was founded on July 23, 1953, as Insta-Burger King, a Jacksonville, Florida–based restaurant chain. After Insta-Burger King ran into financial difficulties, its two Miami-based franchisees David Edgerton (1927–2018) and James McLamore (1926–1996) purchased the company in 1959.

McDonald's Corporation, doing business as McDonald's, is an American multinational fast food restaurant chain. As of 2024, it is the largest by revenue and second-largest by number of locations in the world, behind the Chinese chain Mixue Ice Cream & Tea.

KFC Corporation, doing business as KFC, is an American multinational fast food restaurant chain specializing in Southern fried chicken and chicken sandwiches. Headquartered in Louisville, Kentucky, it is the world's second-largest restaurant chain after McDonald's, with over 31,980 locations globally in 150 countries, as of September 2025. The chain is a subsidiary of Yum! Brands, a restaurant company that also owns the Pizza Hut and Taco Bell chains.