SkyWest Airlines is an American regional airline headquartered in St. George, Utah, United States. SkyWest is paid to staff, operate and maintain aircraft used on flights that are scheduled, marketed and sold by a partner mainline airline. The airline is contracted by Alaska Airlines (as Alaska SkyWest), American Airlines (as American Eagle), Delta Air Lines (as Delta Connection), and United Airlines (as United Express). In all, it is the largest regional airline in North America when measured by fleet size, number of passengers carried, and number of destinations served. SkyWest operates an average of more than 2,400 flights per day to 250 cities in the United States, Canada and Mexico with an extensive network of routes largely set up to connect passengers between smaller airports and the large hubs of its partner airlines.