What Airlines flew out of Concourse B in Atlanta? Navigating Concourse B at Hartsfield-Jackson Atlanta International Airport (ATL) If you're flying out of Hartsfield-Jackson Atlanta International Airport (ATL), you might be wondering which airlines use Concourse B. This post will provide you with a quick rundown of what to expect at Concourse B, including the airlines that depart from there and the amenities available. Airlines Departing from Concourse B: The primary airline using Concourse B is Delta Air Lines, a major hub at ATL. This means you'll find a significant number of Delta's domestic flights departing from Concourse B. In addition, some Alaska Airlines flights also use Concourse B.