Frontier Airlines Denver International Airport is Frontier's main base where it operates its flights out of Concourse A. The ultra-low-cost airline company is well recognized for offering efficient and low-priced travel options. Check-in counters, self-service kiosks, and even TSA PreCheck lanes at the security checkpoint offer convenience and rapid processing at Concourse A. Options for dining, coffee, and retail shops keep customers occupied as they wait for their flights. There's seating that is comfortable and charging stations to keep connected. DEN offers an easy mode of traveling with automated trains which connect the different terminals, parking, and ground transportation. Frontier ensures a smooth journey for both domestic and international travelers.