Frontier Airlines operates out of Terminal E at Philadelphia International Airport (PHL). What Terminal is Frontier Airlines At PHL? Terminal E is dedicated to serving a variety of domestic flights and is equipped with numerous amenities to enhance the passenger experience. Travelers flying with Frontier Airlines at PHL can enjoy convenient access to dining options, retail stores, and comfortable waiting areas within Terminal E. Whether you're arriving or departing, knowing that Frontier Airlines uses Terminal E ensures a smooth and efficient travel experience at Philadelphia International Airport.