Connecting at Chicago O'Hare: Terminals 1–3, Terminal 5 and customs
Published by FlyingOver Editorial Team · Last checked:
At O'Hare, the key question is which terminals. Terminals 1, 2 and 3 are joined inside security, so a connection between them is a walk. Terminal 5 is separate: it handles international arrivals, and getting to or from it usually means either riding the airport train and going through security again, or taking an airside transfer bus that only runs during the day. Customs for international arrivals is also in Terminal 5.
How much time does the airport say you need?
O'Hare doesn't publish a minimum connection time. For international arrivals it says many factors affect how long customs takes, but that it is rare for it to take more than two hours. On one ticket, your airline sold you a connection that meets its minimum and must rebook you if you miss it. Read is a 1-hour layover enough?
Connecting between Terminals 1, 2 and 3
If you arrive on a domestic flight and connect in Terminals 1, 2 or 3, you can walk between them without leaving the secure area. Follow the overhead signs; you don't need the train.
Connecting to or from Terminal 5
You have two options:
| Airport train | Terminal transfer bus | |
|---|---|---|
| Inside or outside security | Outside: you go through security at your next terminal | Inside: no new security check |
| Hours | 24 hours | 11:30 a.m. to 9:30 p.m. |
| Who can use it | Anyone | Connecting passengers with a same-day boarding pass from the terminal they're going to |
| Stops | All terminals; about 10 minutes end to end | Terminal 1 (Gate C18B, moved for construction), Terminal 3 (Gates G17 and K20), Terminal 5 (Gate M13) |
The bus runs between Terminals 1, 3 and 5.
Arriving from another country
International flights arrive at Terminal 5, where U.S. Customs and Border Protection is located:
- Passport control. Follow the corridors to the processing area.
- Claim all your bags, even if they're checked through, and take them through agriculture screening.
- Recheck your bags at the counters just outside the customs area.
- Then either:
- take the free airport train to Terminal 1, 2 or 3 and go through security there, or
- go through security in Terminal 5 and take the transfer bus (daytime hours only).
All connecting passengers go through TSA screening. Pack liquids in your checked bag before you recheck it. Duty-free liquids over 3.4 ounces only get through in a secure, tamper-evident bag.
Precleared flights (for example from Canada or Ireland) arrive as domestic flights. Some arrive in Terminal 5, where you can take the transfer bus to Terminals 1 or 3 without being rescreened; others arrive in Terminals 1–3. Read international to domestic connections.
What's changing
- Terminal 1 construction: Gates B1 to B3 reopened in July 2026, while Gates C1 and C3 closed to build a bridge to a new satellite concourse, Concourse D, due in late 2028. The transfer bus stop moved to Gate C18B.
- Check the terminal on your boarding pass on the day of travel.
Customs wait times
From October 2025 to September 2026, passengers arriving from abroad at ORD waited 17 minutes on average to clear passport control, according to CBP: 13 minutes for US citizens and 24 minutes for visitors. 2.1% waited more than an hour. The slowest arrival hour was 3 p.m.–4 p.m., averaging 22 minutes. These times don't include collecting bags or walking to your next gate. See US customs wait times by airport.
On-time record
From September 2025 to August 2026, 70.7% of scheduled arrivals at Chicago (ORD) reached the gate on time, rank 25 of the 30 busiest US airports. 71.0% of departures left on time and 2.8% of departures were canceled. The largest share of delay minutes came from late-arriving aircraft. See the full US airport on-time ranking.
Follow the first flight
Add both flights to FlyingOver before you travel. You'll follow the first flight offline and see its estimated arrival, and with Premium, connection guidance shows whether your layover looks comfortable, whether you need to keep moving or whether you should go directly to the gate.
Sources
- Chicago O'Hare International Airport (official website, Chicago Department of Aviation), connecting traveler: Terminals 1, 2 and 3 are connected without clearing security again; Terminal 5 is separate; the free 24-hour airport train and the airside terminal transfer bus for connecting passengers with a boarding pass; bus stops; all connecting international passengers clear CBP and recheck bags. (September 16, 2026)
- Chicago O'Hare International Airport (official website), international travel: International arrivals clear CBP in Terminal 5, claim all bags and recheck them outside the CBP area; connecting options by airport train with security at Terminals 1–3 or security in Terminal 5 and the transfer bus from 11:30 a.m. to 9:30 p.m.; precleared passengers; duty-free liquids; it is rare for CBP processing to take more than two hours. (September 16, 2026)
- Chicago O'Hare International Airport (official website), airport train: The airport train takes about 10 minutes from one end to the other and has run around the clock since April 2022. (September 16, 2026)
- Chicago O'Hare International Airport (official website), FAQ: Connecting between Terminals 1, 2 and 3 doesn't require leaving the secure side; CBP is located in Terminal 5. (September 16, 2026)
- Chicago Department of Aviation, Terminal 1 gates reopen (July 1, 2026): Gates B1, B2 and B3 reopened after closing in September 2025; Gates C1 and C3 closed for construction of the bridge to the future Concourse D, due in late 2028. (September 16, 2026)
- US Department of Transportation, Bureau of Transportation Statistics, Reporting Carrier On-Time Performance data: On-time arrivals, departures, cancellations and delay causes at this airport, September 2025 to August 2026, analyzed by FlyingOver. (November 1, 2026)
- US Customs and Border Protection, Airport Wait Times: Passport control wait times at this airport, October 2025 to September 2026, analyzed by FlyingOver. (October 15, 2026)
This article was written based on official sources (see sources). These sources may change over time, and the article may not be updated, so we recommend checking directly with the source or the airline.
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- International to domestic connections: customs, bags, TSAWhere you clear customs when you fly into the US and connect, why you recheck your bags and go through TSA again, and the few exceptions.
- Missed your connection because of a delay? What happens nextWhat airlines owe you when a late first flight makes you miss your connection in the US or Canada, on one ticket or separate tickets, and what to ask for.
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