Baltimore/Washington International Thurgood Marshall Airport (BWI) has one main terminal, five concourses, and a layout that looks simple until you are standing in the wrong one with 40 minutes until your flight. BWI is not a difficult airport. It is a specific one, and knowing how it actually works before you arrive saves the kind of time that matters on a travel day.
Here is everything worth knowing, organized by what actually affects your experience.
BWI has one main terminal divided into five concourses.
BWI runs as a single U-shaped building connected to five concourses, A through E, arranged around a central parking garage. The catch is the split.
Concourses A, B, and C share one airside zone. Concourses D and E share a separate one. Switching between the two groups requires exiting security, crossing the main building, and re-clearing at a different checkpoint. Allow at least 45 minutes for that connection.
Looking at a BWI terminal map before you arrive makes the layout much easier to read. The security split between Concourses A-C and D-E is the one detail most first-time passengers overlook.
Both concourses run exclusively on Southwest Airlines across 25 gates. A $520 million upgrade added a direct walkway between A and B, modernized gates at A1 through A5, a local vendor marketplace featuring a Lexington Market outpost, and a faster baggage system processing 3,400 bags per hour. Southwest also ended open boarding in early 2026, moving to assigned seating, a shift that changes how the A/B gates feel at departure time compared to a year ago.
Southwest, American Airlines, and Contour Airlines share 14 gates here, all within the same airside zone as A and B. Passengers on any of those three airlines can move freely between concourses after clearing security. Minute Suites sit inside Concourse C, private cabins bookable by the hour, with Priority Pass members receiving one hour at no charge. For long layovers or delayed departures, it is one of the more useful spots in the building.
Delta, United, Alaska, Spirit, and Air Canada fly from Concourse D’s 22 gates. The Club at BWI, near gate D10, accepts Priority Pass, Lounge Key, and walk-in entry for a fee, regardless of airline. A Roam Fitness gym sits just past the D/E security checkpoint. One caveat worth noting: Southwest and American travelers from A, B, or C cannot reach The Club without leaving their zone, crossing the main building, and passing through the D/E checkpoint again.
British Airways, Copa Airlines, Icelandair, and select Southwest international routes depart from five gates here. Dining is limited in E, so most travelers eat in Concourse D before heading over. The Maryland Light Rail station sits on the lower level near Concourse E.
BWI has four checkpoints: three covering A, B, and C, and one covering D and E. TSA PreCheck lanes run at all four. CLEAR lanes are available at the main terminal and in Concourse D.
One thing most people do not know is that checkpoints open at 4 a.m., even though the airport itself runs around the clock. Early morning departures before that window have no security access, a detail that catches overnight travelers off guard more often than it should.
MARC Penn Line and Amtrak stop at BWI Rail Station with a free shuttle to the terminal running every 10 to 15 minutes. For travelers from Washington D.C., MARC is the most consistent option. In the Baltimore city center, the Light Rail to Concourse E on the Light Rail is $1.90, with no transfer needed.
Travelers coming from Annapolis, the Eastern Shore, Northern Virginia, or Southern Maryland rely on ground transportation. Drivers approaching BWI typically arrive via I-195, which connects directly to the Baltimore-Washington Parkway (MD-295) and I-95. During weekday mornings and late afternoons, both corridors carry significant commuter volume, so building in extra time is worthwhile.
Some travelers book a private airport transfer to BWI to avoid post-flight coordination entirely, especially for early-morning departures or late-night arrivals when other options thin out.
If you are not on Southwest, you are in Concourse D or E – a separate security checkpoint from the A/B/C side. Check which checkpoint applies before joining a line.
The A/B marketplace features local Baltimore vendors and offers noticeably better food options than most airport concourses. Worth a stop if you have time before a Southwest departure.
Connecting between the A/B/C group and D/E with under 45 minutes is not realistic. The re-security requirement is real, the checkpoints queue, and the walk between them is longer than it looks on a map.
A straightforward guide based on trip type:
The 4 a.m. checkpoint opening is the one hard constraint. No amount of early arrival helps if security has not opened yet.
BWI has family restrooms and nursing rooms throughout the concourses, wheelchair assistance available through participating airlines, elevators at all key points in the terminal, and accessible parking near each entrance. Travelers who need mobility assistance should notify their airline before arriving so support is ready at the gate rather than requested on arrival.
Baggage claim, taxis, rental car shuttles, and the rideshare lot are all on BWI’s lower level. The Light Rail station near Concourse E is also down here. For anything left at a security checkpoint, the TSA lost and found is on the lower level opposite door 9.
Checked baggage arrives on the lower level, organized by airline. Digital displays above each carousel show the assigned claim belt once your flight lands. Knowing the lower level layout before you land saves the circular walk that most first-time BWI arrivals do at least once.
