What terminal is Frontier at DEN? Travelers can find efficiency and convenience at the Frontier Airlines terminal at Denver International Airport (DEN). It is primarily situated in Concourse A and provides a simple and convenient experience for travelers. Self-service kiosks and friendly staff make check-in quick and simple. After passing security, there are a number of restaurants, retail stores, and cozy places to unwind before your trip. Ample charging stations guarantee your gadgets are prepared for the trip, and free Wi-Fi keeps you connected. Frontier Airlines, which is well-known for its low prices and environmentally sustainable operations, ensures that every traveler has a comfortable and economical trip through Denver.