ORD airport guide

Chicago O'Hare (ORD) Airport Guide: Terminals, Transport and Tips

Chicago O'Hare International Airport, Chicago, United States: terminals, getting to the city, security, lounges and connections.

Quick answer: O'Hare has four terminals: 1, 2 and 3 are joined airside and handle United and American, while Terminal 5 is a separate building for Delta and most foreign airlines. The free Airport Transit System (ATS) train links all four 24 hours a day, and the CTA Blue Line runs around the clock to downtown Chicago in about 40-45 minutes.

Facts checked November 2026. Schedules and entry rules change, so confirm with the airline and the official government site before you travel.

ORD at a glance

Terminals	1, 2, 3 and 5 (there is no Terminal 4)
Main airlines	United (Terminals 1 and 2), American (Terminal 3), Delta and most foreign airlines (Terminal 5)
Between terminals	Walk airside between 1, 2 and 3; free ATS train (landside, 24/7) or the airside Terminal Transfer Bus to reach 5
To downtown by train	CTA Blue Line, 24 hours, about 40-45 minutes
International arrivals	Customs at Terminal 5 for most flights; collect and recheck bags before connecting
Wi-Fi	Free in every terminal, before and after security (ad-supported)
Construction	O'Hare 21 rebuild under way; Terminal 2 is to be replaced by a new Global Terminal

Which terminal is my airline in?

O'Hare's terminals are numbered 1, 2, 3 and 5. The airport lists 199 gates as of April 2026: Terminal 1 has Concourses B and C, Terminal 2 has E and F, Terminal 3 has G, H, K and L, and Terminal 5 has Concourse M.

United, which leases the most gates at O'Hare, flies from Terminal 1 and Terminal 2. American flies from Terminal 3. Delta moved every one of its O'Hare flights, domestic as well as international, from Terminal 2 to Terminal 5 in October 2022, so it now sits beside its SkyTeam partners such as Air France and KLM. Most other foreign airlines also use Terminal 5.

Southwest no longer serves O'Hare: it ended its O'Hare flights in June 2026 and runs all its Chicago flying from Midway. Assignments shift during construction, so check the terminal on your boarding pass or the airline's app before you leave home.

Getting between terminals: ATS train and transfer bus

Terminals 1, 2 and 3 are connected on the secure side, so you can walk between them without clearing security again. Terminal 5 has no walkway to the other three.

The Airport Transit System (ATS) is a free automated train that runs 24 hours a day between Terminals 1, 2, 3 and 5 and the Multi-Modal Facility, where the rental car counters, Economy Parking Lot F and the Metra and Pace connections are. The airport says an end-to-end ride takes about 10 minutes and trains run every 3-5 minutes at peak times. The ATS is landside, which means you leave security to use it and are screened again at your next terminal.

For connecting passengers there is also the airside Terminal Transfer Bus between Terminals 1 and 5 and between Terminals 3 and 5. As posted by the airport, it runs every 15 minutes from 11:30 a.m. to 9:30 p.m., and you need a boarding pass for a same-day departure from the terminal you are heading to. Stops are at Gate C18B in Terminal 1, Gates G17 and K20 in Terminal 3, and Gate M13 in Terminal 5. Outside those hours, take the ATS and go back through TSA.

Getting to downtown Chicago

The CTA Blue Line starts at the O'Hare station, reached by walkway from Terminals 1, 2 and 3 (from Terminal 5, ride the ATS first). Trains run 24 hours a day and the CTA gives a normal travel time of about 40-45 minutes to downtown.

Taxis and rideshare pickups are at each terminal, and journey time to the Loop depends heavily on traffic on the Kennedy Expressway. Rental cars, Metra commuter trains and Pace suburban buses are all reached from the Multi-Modal Facility on the ATS.

Security, arrival times and international arrivals

TSA PreCheck lanes are listed at checkpoints in every terminal, including Terminal 5, and the airport's TSA page posts the hours for each checkpoint. Early-morning departure waves can be busy, so arriving two hours before a domestic flight and three hours before an international one is a sensible margin. Most checkpoints outside Terminal 5 close in the evening, and PreCheck hours are shorter than standard lanes.

If you land from abroad on a flight that did not clear US customs before departure, you go through CBP and collect all checked bags, even when you are connecting. Most international flights arrive at Terminal 5. After customs, recheck your bags, then take the ATS or the transfer bus to Terminals 1, 2 or 3, where you are screened again.

Terminal 5 checkpoint CP10 is listed by the airport as open 24 hours for standard screening, which helps on late-night international departures. If you are leaving from Terminal 5 on an airline other than Delta, check in there directly rather than at Terminals 1-3, because the ATS ride and a second screening add time.

Lounges by terminal

Terminal 1 has United Clubs near Gates B6, B18 and C10 and the United Polaris lounge near Gate C18, which is for international business and first class. Terminal 2 has United Clubs near Gates E7 and F9.

Terminal 3 has American's Admirals Clubs near Gates G8, L2A and H6/K6, and the Flagship Lounge at H6/K6. Terminal 5 has the Delta Sky Club near Gate M13, the Air France lounge near M17, the LOT Business Lounge near M18 and the Wingtips Lounge near M19, which several foreign airlines use for their premium passengers.

O'Hare 21: what is being built

O'Hare 21 is the city's rebuild of the terminal area. Terminal 5 has already been expanded. Next come two satellite concourses west of the current terminals, and a new Global Terminal that replaces Terminal 2.

The schedule has moved. A DePaul University report released in November 2026 expects the two satellite concourses by 2030 and the Global Terminal in 2033; the city's Aviation Department has not published firm opening dates, so treat these as estimates. Expect detours, temporary gate changes and longer walks around construction zones. The Terminal 1 bus stop at Gate B1, for example, is closed for construction.

Connection tips

A United-to-United or American-to-American domestic connection inside Terminals 1-3 is usually a walk. The connections that catch people out involve Terminal 5: a Lufthansa or British Airways arrival connecting to United or American, or a Delta flight connecting to a United partner, means changing buildings.

When you book separate tickets, leave plenty of time, because you may have to claim bags, re-check in and clear security again. Free Wi-Fi is available in every terminal before and after security under the network names Boingo Hotspot or Free ORD Wi-Fi.

Frequently asked questions

What terminal is international at O'Hare?

Terminal 5 is the international terminal. Most foreign airlines depart from it and most international arrivals clear customs there. United and American can also run international departures from their own Terminals 1 and 3.

What terminal is Delta at O'Hare?

Terminal 5. Delta moved all of its O'Hare flights, domestic and international, from Terminal 2 to Terminal 5 in October 2022.

Can you walk between terminals at O'Hare?

Between Terminals 1, 2 and 3, yes, on the secure side. Terminal 5 has no walkway, so use the free ATS train (outside security) or the airside Terminal Transfer Bus, which runs 11:30 a.m. to 9:30 p.m. for connecting passengers.

How long is the Blue Line from O'Hare to downtown?

The CTA gives a normal travel time of about 40-45 minutes. The Blue Line runs 24 hours a day from the O'Hare station next to Terminals 1-3.

Does Southwest fly from O'Hare?

No. Southwest ended its O'Hare service in June 2026 and now serves Chicago only from Midway.

Where is the United Polaris lounge at O'Hare?

In Terminal 1 near Gate C18, for passengers flying international business or first class.