Navigating Chicago O'Hare International Airport (ORD) doesn't have to be overwhelming if you know the layout before you arrive. O'Hare operates with four active terminals—numbered 1, 2, 3, and 5 (there is no Terminal 4)—handling hundreds of thousands of passengers daily. Terminals 1, 2, and 3 form a massive, interconnected domestic core that you can walk between airside, while Terminal 5 sits on the outer edge as the primary international hub.
Knowing your specific airline and terminal assignment before leaving home saves you from expensive parking mix-ups or stressful terminal transfers. United Airlines dominates Terminal 1, American Airlines anchors Terminal 3, and most major international carriers along with Delta operate out of Terminal 5.
O'Hare Terminal Layout and Airline Directory
O'Hare's terminal design reflects decades of expansion. Understanding which airline sits where prevents you from entering the wrong security checkpoint.
Terminal 1
Terminal 1 handles primarily United Airlines and its Star Alliance partners. It features two concourses: Concourse B and Concourse C. These concourses connect via an underground pedestrian tunnel featuring neon lights and famous kinetic art installations.
- Airlines: United Airlines, Lufthansa, ANA.
- Key Features: Multiple United Clubs and the high-end United Polaris Lounge located in Concourse C.
Terminal 2
Terminal 2 is the smallest of the domestic terminals, handling a mix of domestic and Canadian carriers. It features Concourse E and Concourse F.
- Airlines: Air Canada, Alaska Airlines, JetBlue.
- Key Features: Serves as a central connection point between Terminals 1 and 3, featuring a Delta Sky Club (though Delta flights operate out of T5) and the airport's main Travelers Aid desk.
Terminal 3
Terminal 3 is a sprawling structure handling American Airlines and several domestic partners. It contains four distinct concourses: G, H, K, and L.
- Airlines: American Airlines, Iberia, Japan Airlines (departures).
- Key Features: Several Admirals Clubs and the American Airlines Flagship Lounge near the H/K gates.
Terminal 5
Terminal 5 is O'Hare's international gateway, containing Concourse M. Following major expansion projects, it now accommodates a mix of international flag carriers and domestic low-cost carriers to ease congestion in the domestic core.
- Airlines: Delta Air Lines, Southwest Airlines, British Airways, Emirates, Air France, KLM.
- Key Features: Extensive duty-free shopping, multiple airline partner lounges, and the federal customs and border protection facility on the lower level.
How to Get Between O'Hare Terminals
Moving between terminals depends entirely on whether you've already cleared security and whether you're traveling domestically or internationally.
+-------------------------------------------------------+
| O'HARE TERMINAL TRANSFER PATHS |
+-------------------------------------------------------+
| Terminals 1, 2, & 3 -> Walk airside or landside |
| Terminal 5 to T1/T2/T3 -> Use ATS train or airside bus|
+-------------------------------------------------------+
Walking Between Terminals 1, 2, and 3
You don't need a train or a bus to move between Terminals 1, 2, and 3. Marked pedestrian walkways link all three structures both before security (landside) and after security (airside).
- The walk from Terminal 1 to Terminal 2 takes about 5 to 10 minutes.
- Moving from Terminal 2 to Terminal 3 takes another 5 to 10 minutes.
- Total end-to-end walking time across the domestic core sits around 20 minutes.
Using the Airport Transit System (ATS)
To reach Terminal 5 from the domestic terminals—or to get to the Multi-Modal Facility (MMF) for rental cars and economy parking—you must use the Airport Transit System (ATS). This automated people-mover train runs 24 hours a day, 7 days a week, arriving every few minutes. The ride from the domestic terminals to Terminal 5 takes roughly 10 minutes. Stations sit outside the terminal core; follow the overhead airport signs across pedestrian bridges to reach the platform.
Airside Terminal Transfer Buses
If you are connecting from an international flight arriving at Terminal 5 to a domestic flight in Terminals 1, 3, or vice versa, you can use the airside Terminal Transfer Bus to avoid exiting security and re-entering through standard checkpoints.
- Pickup Locations: Gate M13 in Terminal 5, Gate B1 in Terminal 1, and Gates G17 and K20 in Terminal 3.
- Note: These buses operate during specific daytime hours (typically 11:30 a.m. to 9:30 p.m.). Verify current schedules with airline agents upon arrival.
Security Checkpoints, PreCheck, and CLEAR
O'Hare features security checkpoints in every terminal. Wait times fluctuate wildly depending on the bank of departing flights, morning business rushes, and holiday travel surges.
- TSA PreCheck: Dedicated PreCheck lanes operate across Terminals 1, 2, 3, and 5. Check operating hours ahead of time, as some checkpoints close by early evening.
- CLEAR Plus: Biometric CLEAR lanes operate in Terminal 1, Terminal 2, and Terminal 5, speeding up identity verification before standard security screening.
- Standard Strategy: If you're flying out of the domestic core, you can clear security in any of the three connected terminals (1, 2, or 3) and walk to your departure gate, regardless of which terminal your airline uses. If Terminal 1's main checkpoint looks jammed, check Terminal 2 or 3.
For official details on checkpoint closures and real-time wait estimates, check the Chicago Department of Aviation portal before heading to the airport.
Ground Transportation and Getting Downtown
Leaving O'Hare requires choosing between rail transit, taxis, rideshares, or rental cars.
CTA Blue Line Train
The Chicago Transit Authority (CTA) Blue Line offers the most reliable way to beat Chicago traffic. Station platforms sit directly on the lower level of the main parking garage, accessible via the pedestrian tunnels from Terminals 1, 2, and 3.
- Cost: $5 from the airport station.
- Duration: Roughly 45 minutes to downtown Chicago (the Loop).
- Schedule: Runs 24 hours a day, 7 days a week.
Taxis and Rideshares (Uber and Lyft)
App-based rideshares pick up passengers on the upper level (departures) for Terminal 2, or designated zones depending on current airport traffic updates. Always follow the app instructions once you request a ride. Taxis line up outside the baggage claim areas on the lower level of each terminal. Expect a 30- to 60-minute ride into downtown Chicago depending on the time of day and Dan Ryan or Kennedy Expressway traffic.
Common Mistakes to Avoid at O'Hare
- Going to the wrong terminal for international flights: While most international flights use Terminal 5, Canadian carriers with U.S. preclearance operate out of Terminal 2. Always check your boarding pass first.
- Ignoring the walking distance: O'Hare is massive. Walking from a Concourse B gate in Terminal 1 out to a distant Concourse L gate in Terminal 3 can take 15 to 20 minutes. Wear comfortable shoes.
- Forgetting baggage re-check on international connections: If you land at Terminal 5 from abroad and connect to a domestic flight, you must clear customs, collect your checked bags, drop them off at the re-check belt, and go back through TSA security. Budget at least two to three hours for this transfer.
- Mistaking Midway for O'Hare: Chicago has two major airports. Ensure your flight originates or lands at ORD (O'Hare) rather than MDW (Midway), which sits closer to the city center and serves mostly Southwest Airlines.
Frequently Asked Questions
Is there a train between O'Hare terminals?
Yes. The Airport Transit System (ATS) is a free 24/7 automated train that connects all four terminals (1, 2, 3, and 5) as well as the Multi-Modal Facility for rental cars and economy parking lots.
Can I walk between Terminal 5 and the other terminals?
No. Terminal 5 is completely detached from the domestic core. You cannot walk between Terminal 5 and Terminals 1, 2, or 3. You must ride the ATS train landside or take the airside terminal transfer bus if you qualify.
What is the best way to get from O'Hare to downtown Chicago?
The CTA Blue Line train is the fastest budget option, taking about 45 minutes to reach downtown for $5. Taxis and rideshares offer door-to-door service but face unpredictable highway traffic delays.
Do I need to clear security again when connecting terminals?
If you stay airside and use the designated terminal transfer bus (or walk between Terminals 1, 2, and 3), you do not need to re-clear security. However, if you exit to baggage claim or arrive on an international flight at Terminal 5, you must exit security and go through a standard TSA checkpoint again.
