OSI Group is a privately held food company headquartered in Warrenville, Illinois, that makes custom value-added food products for foodservice and retail food brands and manages food supply chains from sourcing to distribution. Its product capabilities cover beef, pork and poultry processing, bacon, sausages, pizza and baked snacks, sandwich assembly and produce. The company traces its origins to 1909, when Otto Kolschowsky opened a family meat market in the Chicago area, and says it became McDonald’s first supplier of fresh ground beef in 1955.
OSI reports about 20,000 employees and more than 65 facilities in 18 countries and regions, including sites in India and the United Kingdom. It ranks 67th in Food Engineering’s 2026 Top 100 Food and Beverage Companies, which estimates its food sales at $8,200 million.