Technomic ranked the biggest fast-food, fast-casual, and casual-dining chains in the US. Irene Jiang / Business Insiderlighning bolt icon An icon in the shape of a lightning bolt. It's a full-on food fight as taco chains, burger joints, and sandwich shops all vie to become the biggest restaurant chain in the US. McDonald's topped the list as the biggest restaurant chain in the US, though Nation's Restaurant News reported that growth across the three biggest chains slowed this year: They experienced a combined sales increase of 1.2% in 2024, compared to a combined sales increase of over 11% in 2023. Here are the 15 biggest restaurant chains in the US, ranked.