Frontier Airlines ATL Terminal Operating out of Concourse D at Hartsfield Jackson Atlanta International Airport (ATL) is Frontier Airlines. Travelers on Frontier flights should report to Terminal North for baggage claim and check-in, and then pass through security to reach Concourse D. The terminal has a number of services, such as restaurants, stores, and places to charge devices. Although Frontier's flights are renowned for their affordable prices, keep in mind that extra costs can apply for extra luggage and seat preference. It is advised to arrive early to give yourself enough time for security screening and check-in, particularly during periods of high travel demand.