Frontier Airlines ATL TerminalFrom Concourse D, which is reachable via Terminal North, Frontier Airlines flies out of Hartsfield-Jackson Atlanta International Airport (ATL). Prior to passing through security and arriving at Concourse D, where Frontier's gates are situated, travelers need check in at Terminal North. This terminal has a number of facilities, such as eating options, retail stores, and charging areas. Because Frontier Airlines is a budget airline, travelers should be ready to pay extra for extra amenities like seat preference and checked baggage. Arriving early is advised to provide time for security checks, gate access, and check-in, particularly during peak travel times.