Southwest Airlines ONT Terminal is located in Terminal 4 at Ontario International Airport. This terminal offers travelers a pleasant and efficient experience, with Southwest's ticketing and check-in desks, as well as self-service kiosks for faster check-in. Before boarding, passengers can choose from a variety of food and retail alternatives. The terminal also provides amenities like free Wi-Fi and enough seating. It offers easy access to parking and ground transportation, ensuring a stress-free journey through ONT.