What Terminal is Spirit Airlines At IAH? Spirit Airlines operates out of Terminal A at George Bush Intercontinental Airport (IAH) in Houston. Terminal A is well-equipped with a variety of amenities, including dining options, retail stores, and comfortable seating areas to enhance the travel experience for Spirit Airlines passengers. The terminal is designed for efficiency, ensuring smooth check-in and security processes. Convenient ground transportation and parking facilities are also available, making it easy for travelers to access the terminal and catch their flights on time.