For passengers arriving on international flights, Immigration and Customs^{[dead link]} formalities typically take 15-30 minutes, but can take over 2 hours at peak times. The busiest times are in the afternoon, and the full statistics can be seen here.

Passengers transferring between international flights should note that there are no special transit facilities, which means that even if you have an immediate connecting flight, you have to pass through Customs and Immigration. After you clear customs, but before you exit into the public area, there are some check-in counters run by the major mainline carriers for you to check your bags that have already been checked through to the final destination, so you don't have to lug your bag to Terminals 1-3. For details of entry and visa requirements see get in section of United States page. Passengers arriving on international flights and transferring to another international or domestic flight will have to go through security again.

For passengers transferring between from domestic flights (or from international flights from airports with US border preclearance), Terminals 1-3 are connected to each other both landside and airside, so if your luggage is checked through, you do not need to clear security again. Terminal 5 is in a completely separate area and not physically connected to Terminals 1-3, so you will have to exit the restricted area and go through security again after transferring using the AirTrain.

This major renovation plan, named due to its planned full completion in 2021, is already making an impact in the airport. For example, the first new gates in two decades (the L Stinger concourse for American Eagle regional jets), the temporary closure of the ATS for renovation and extension, the new Multi-Modal facility, and the move of all Delta and Frontier flights - even domestic ones - to Terminal 5 have already happened.

The long term plan is that the Terminals 1-3 complex will become a unified Global Terminal with customs implementation as well as TSA and landside amenity improvements. This Global Terminal will make O'Hare the first North American airport to be built around the airport alliances as United and Star Alliance carriers as well as American and Oneworld airlines will move there while Delta and their SkyTeam partners will move to the current Terminal 5, which will be extended to meet the demand.

The 41.9781-87.90292 CTA Blue Line terminates at the space-age station for O'Hare, designed by the firm of architect Helmut Jahn. Trains run 24 hours a day, as frequently as every six minutes during peak periods and as infrequently as every half-hour overnight. The trip to the Loop should take about 48 minutes, but never cut things close with the CTA. The station is located beneath the Bus/Shuttle Center, closest to Terminal 2 but easily accessible by underground passages, with moving walkways, from Terminals 1 and 3. Those arriving at or departing from Terminal 5 (international) must take the automated Airport Transit System between Terminals 2 and 5. The cost of the train from O'Hare is $5 instead of the regular $2.50 anywhere else in the city. When taking the CTA to O'Hare, it's recommended to board the train at the front in the O’Hare direction, as the entrance is at the front of the train (back of the train in the Forest Park direction). You do not need to pay the extra fare upon exiting the station. Get off at the Clark/Lake Station in downtown Chicago (the 'Loop') and transfer to the Orange Line train to continue to Chicago Midway Airport. Get off the Blue Line train at the Clinton Station and walk up a couple blocks on Clinton St to reach Union Station.

41.9951-87.88043 Metra North Central Service (NCS) trains stop at the "O'Hare transfer" station, located adjacent to parking lot F (with shuttle bus service connecting to the ATS at the Remote Parking stop). The train reaches Chicago's Union Station in approximately 30 minutes, but service is infrequent, operates only on weekdays and is concentrated in the peak commute direction. In the future, Metra-ATS transfers will be direct at a new consolidated rental center.

Pace is one of the three transit agencies (the others are Metra and CTA) serving the surrounding suburbs of Chicagoland in Cook, Lake, Will, Kane, McHenry, and DuPage counties with the following routes going directly into the Multi-Modal Facility (MMF):

• Routes 250 and Pulse Dempster Line go north to Des Plaines/Des Plaines Metra Station; and then east towards Evanston via Skokie on Dempster St. Both run along the same route except the 250 route makes more local stops along the way then the Pulse Dempster Line.
• Route 330 goes south towards Harlam / Archer in Summit via Manheim (US 12) and Granger Roads. It stops at the Rosemont (CTA) Station and La Grange Road Station (Metra BNSF Line; Amtrak Illinois Zyphyr and Carl Sandburg trains).

There are additional ("airport") Pace bus routes from Rosemont (CTA) Station and the Cumberland (CTA) Station, the next two stops in the surrounding areas, on the CTA Blue Train from O'Hare. The station names in the above are linked to the PACE website listing the PACE bus routes serving the two stations in Rosemont.

Chicago taxis^{[dead link]} charge a metered rate based on time and distance. Expect to pay around $45 (plus tip) from O'Hare to the Loop. It is illegal for Chicago taxis to charge a non-metered flat rate except for special shared-ride services. Taxi drivers rarely participate in shared-ride services.

Except for a few suburbs immediately adjacent to the airport, Chicago taxis charge one and a half times the meter rate for non-Chicago destinations. Most suburban taxi companies have flat-rate taxi service to their respective suburbs. It is illegal for a suburban taxi to take you from O'Hare to a point within the City of Chicago. American Taxi^{[dead link]}, Universal Taxi and 303 Taxi are three large suburban taxi associations that have taxis stationed near the airport. But the suburban taxis cannot come to the airport unless you call them after you arrive.

Of the many shuttle/limo services, Go Airport Express vans are the most commonly seen doing the rounds of downtown hotel pick-ups. Fares to the downtown business district are $32/46/54 (plus tip) for a party of one/two/three persons, with a discount for a return ticket if bought in advance and lower fares for children under 14.

Ride app pick-up zones are on the upper level (the departure level) of Terminal 2. If your flight lands at any of the other terminals, you will need to make your way to Terminal 2 to be picked up by a ride share. Only premium services such as Uber Black and Lyft Black are allowed to pick up passengers at the arrival level of all terminals.

Except with Greyhound Lines the airport intercity bus and shuttle companies stop at the Multi-Modal Facility (MMF) outside the airport grounds (10255 W Zemke Blvd):

• CoachUSA/Wisconsin Coach, O'Hare Airport, toll-free: +1-877-324-7767. Offers 14 buses daily, departing every hour, from O'Hare to Kenosha, WI; Racine, WI; Brookfield/Waukesha, WI; Milwaukee and Mitchell Airport ORD to Milwaukee $28. 
• CoachUSA/Van Galder (service from O'Hare Airport, Midway Airport, and Union Station), toll-free: +1-800-747-0994. Frequent bus service to Janesville, WI; Madison, WI; South Beloit, IL; and Rockford, IL. 
• Lafayette Limo, ☏ +1 756 497-3828. Various locations on Purdue University's West Lafayette, IN campus. (updated Apr 2023)
• Peoria Charter, toll-free: +1-800-448-0572. Connects Chicago O'Hare, Union Station and Chicago Midway to certain suburbs to Peoria (Bradley, City Link), Normal (IL State, IL Wesleyan, Amtrak Uptown Station), Bloomington/Normal Airport, Champaign (University of IL, Amtrak IL Terminal). (updated Apr 2023)
• Reindeer Shuttle, ☏ +1 765 637-5124. Serves Chicago, Purdue University (West Lafayette, IN) Indianapolis, IN, and Crestwood, IL. (updated Apr 2023)
• Greyhound Lines, (bus stop) Cumberland CTA Station @ 5800 N Cumberland Ave (Connected to the airport via CTA Blue Line train), ☏ +1 800 231-2222. Full service station at 630 W Harrison St in downtown. (updated Dec 2023)

To reach the downtown bus station (Greyhound & Burlington Trailways) at 630 W Harrison St, take the CTA Blue Line train from O'Hare to Clinton Station. Walk one block south on S Clinton St to Harrison and go a couple blocks west, along Harrison, towards S Des Plaines St to reach the bus station (Harrison & Des Plaines).

Access to O'Hare's terminals is via I-190, which originates near the interchange between I-294 (the Tri-State Tollway) and I-90 (the Northwest Tollway to the northwest and the Kennedy Expressway to the east). From downtown Chicago, follow I-90/94 northwest, continue on I-90 when I-94 splits off, then follow I-190 into the airport, which splits eventually into arrival (lower-level) and departure (upper-level) roadways serving Terminals 1, 2, and 3 in turn. For Terminal 5, exit on Bessie Coleman Drive. This exit also serves numerous rental car companies and the economy parking lots. To drop off a passenger without the harrowing experience of navigating the departures roadway, try Kiss n'Fly: follow signs for remote lot E where you can leave your friend at the terminus of the Airport Transit System, just a short ride away from the terminals.

Most major car rental companies are located in the Multi-Modal Facility (MMF) which is connected from the passenger terminals via Airport Transit System (ATS) train. Call to arrange shuttle pick-up by off-airport car rental companies at MMF (10255 W. Zemke Blvd).

Passengers may walk between Terminals 1, 2, and 3 both land-side (prior to clearing security) and air-side. The distance can be considerable; make sure to allow adequate time for layovers between different terminals.

United Airlines runs an air-side shuttle bus between Gate E2A in Terminal 2 and Gate C9 in Terminal 1 (convenient for people going from a United Express flight to a Star Allaince flight). There is also a bus stopping at gates G17, K20 and L24 in Terminal 3 before going to Terminal 5, allowing you to bypass the security checkpoint there. Due to immigration and customs processing, you can't take the bus back.

O'Hare has an automated, land-side, transit system cleverly called Airport Transit System or ATS. Stops are made at all four terminals (and Lot D at Terminal 5), remote parking lot E and the Multi-Modal Facility (MMF) for rental cars, Lots G & H; Metra train, intercity buses & shuttles, and Pace buses. This is the only way to reach the three domestic terminals and the Blue Line station from the international terminal, which means that passengers connecting to or from a Terminal 5 flight should allow abundant time for border formalities, inter-terminal transit, and a second security screening. There is no charge for the use of the ATS.

• Garrett's Popcorn, Terminal 1 B and Terminal 3 H. 6AM-10PM. Oprah's taste in popcorn perhaps exceeds even her taste in books, and her favorite Chicago popcorn shop has two locations in the airport. Drench those little guys in caramel, cheese, etc., and toss in some macadamias, cashews, and almonds, and you have yourself a meal. S/M/L $3-5-7. 
• Gold Coast Dogs^{[dead link]}, 6AM-8PM, serves airport versions of Chicago-style hot dogs in Terminal 3. It would be a crime against taste if this was your only encounter with a Chicago-style hot dog, with Superdawg only a short distance away on the Far Northwest Side!
• McDonald's, 5AM-11PM, has its greasy claws in all four terminals and is notable mainly for being open later than anyone else.
• Nuts on Clark. 6AM-10PM in Terminals 1, 2, and 3, has tasty popcorn & nuts for a takeaway salty fix. 
• Sky Bridge, 5AM-9PM daily, is run by Greeks and serves gyros, kebabs, and some other Greek fare along with the basic burger and dog. A step up for the usual fast food joint, most meats here aren't cooked until you order. The omelets are good, the hash browns greasy. Terminal 2, near F7.

• 41.980578-87.9099681 Berghoff Café. 5:30AM-9:30PM. Lives on in Terminal 1 C26, outlasting the original nineteenth century location in the Loop. Bratwurst loyalists will have to take the classic German food wherever they can get it! Of course, you'd miss this, thinking it was just another shoddy airport sandwich shop, but for the lines. The Berghoffés beer or root beer goes just right with a signature Berghoff reuben. $8-12. 
• Billy Goat Tavern & Grill, 6AM-9:30PM, serves beer, steaks, and cheeseburgers in Terminal 1. For the sake of any locals who might be around, travelers should take it as a given that everyone has already heard their John Belushi impression, thanks.
• Chili's, 5:30AM-9PM, serves a limited version of their burgers-and-pasta menu in Terminals 1, 2, and 3.
• Johnny Rockets, 6AM-9:30PM, airport version of the retro-diner/soda fountain hamburger chain in Terminal 2. Mixed reviews compared to a real standalone JR, but it's a change of pace from a fast-food burger.
• Pizzeria UNO, 5:15AM-9:30PM, slums it in Terminals 1, 2, and 5, pushing watery versions of Chicago's hallmark deep dish pizza, while Reggio's does the same in Terminals 1 and 3.
• Tortas Frontera. Rick Bayless of the very highly acclaimed Frontera Grill & Topolobampo downtown runs what is almost certainly the only airport sandwich shop that lists the local farms from which it gets its produce and meat! The tortas (Mexican sandwiches) are of a high enough quality to land this place in top ten lists of the best airport restaurants worldwide, and it's just a sandwich shop! The Bloody Marys are there waiting for you in the morning after an overnight. $8-14. 
  • 41.980028-87.9066792 Tortas Frontera T1, Terminal 1, B11. Daily 5:30AM-9PM. Only location with online ordering. 
  • 41.975435-87.9001373 Tortas Frontera T3, Terminal 3, K4. Daily 5:30AM–9PM. 
  • 41.974154-87.8902764 Tortas Frontera T5, Terminal 5, M12. Daily 10AM-9PM. No allergen info for this location. 
• Burrito Beach, Terminal 2 (gate K4). Mexican food, a Chipotle imitator. The food is just okay, but for vegan travelers it's one of the few places in O'Hare where you can find a meal that will actually fill you up (and for less than $10). $8-12. (updated Jun 2019)

• Romano's Macaroni Grill, 8AM-8PM, Terminal 3 gate K3, has entrées priced mostly in the $10-$16 range, topping out at $28 for high-end steak meals. Food is of good quality, comparable to the standalone Macaroni Grill restaurants, though is a little more oily than standard Italian fare.
• Wolfgang Puck, 5AM-10PM, in Terminals 1 and 3 has an extremely limited menu to compensate for demand and limited preparation space. It's overpriced and not tasty enough to justify the price, but if you're on an expense account, go for it.

For passengers departing on international flights there are some somewhat limited duty free shopping possibilities:

• Liberty Duty Free, Terminal 1 Gate B9; Terminal 1 Gate C17; Terminal 2 Gate F1; Terminal 3 Gate K5. Four shops selling alcohol, perfume and tobacco. 
• Dufry, Terminal 5, Concourse M, ☏ +1-773-686-0726. Three kiosks, by gates M8, M10 and M14. 

Cheap hotels near O'Hare tend to be cheap for a reason — don't be shy about asking to see the room first.

• 42.00985-87.871192 Comfort Inn O'Hare (Des Plaines), 2175 E Touhy Ave, Des Plaines, ☏ +1-847-635-1300. About two miles (3 km) from the airport. Rooms from $90. 
• 41.94762-87.884773 Quality Inn O'Hare Airport, 3801 N Mannheim Rd, Schiller Park, ☏ +1-847-678-0670. About two miles (3 km) from the airport. This building used to be a Holiday Inn, and it was here that Murph and the Magic Tones played in the movie The Blues Brothers. Rooms from $60. 

• 41.9774-87.86714 Aloft Chicago O'Hare, 9700 Balmoral Ave, Rosemont, ☏ +1-847-671-4444. The budget-minded imprint of the W. Styled to be young and trendy, the hotel offers a ton of the same great amenities of the pricier Marriott properties. Swanky bar, cool design, and great entertainment set-up in each room. Rooms from $89. 
• 41.99891-87.886255 Best Western At O'Hare, 10300 W Higgins Rd, Rosemont, ☏ +1-847-296-4471. The rooms are a little dingy and the internet was spotty at last check, but it's not bad. Has a sports bar and a diner on-site. Rooms from $130. 
• 42.02486-87.960786 Best Western O'Hare/Elk Grove Hotel, 100 Busse Rd, Elk Grove Village, ☏ +1-847-593-8600. Check-in: 3PM, check-out: 11AM. About five miles (8 km) from the airport. 
• 41.95554-87.859987 Comfort Suites O'Hare (Schiller Park), 4200 N River Rd, Schiller Park, ☏ +1-847-233-9000. Big hotel with a sports bar and grill on-site. Rooms from $120. 
• 41.97911-87.863148 Embassy Suites Chicago O'Hare/Rosemont, 5500 N River Rd, Rosemont, ☏ +1-847-678-4000. About one mile (2 km) from the airport. Rooms as low as $119, but reservations can be difficult to get. 
• 41.95561-87.882829 Four Points by Sheraton, 10249 W Irving Park Rd, Schiller Park, ☏ +1-847-671-6000, toll-free: +1-800-323-1239. Lounge, restaurant, pool, and the rest. For travelers who like to cut it close, shuttles run to O'Hare every 20 minutes, 24 hours per day. Rooms from $155. 
• 41.94998-87.8851210 Hampton Inn Chicago O'Hare Airport Hotel, 3939 N Mannheim Rd, Schiller Park, ☏ +1-847-671-1700. About 1.5 miles (2 km) from the airport. Rooms from $146. 
• 41.99962-87.8855211 Staybridge Suites Chicago O'Hare Airport, 6600 N Mannheim Rd, Rosemont, ☏ +1 847-380-5800. About five miles (8 km) from the airport. Rooms from $163. 
• 41.98124-87.8589612 Hyatt Regency O'Hare, 9300 W Bryn Mawr Ave, ☏ +1-847-696 1234. Contemporary facility with newly renovated guest rooms and meeting space. Rooms from $159. 
• 42.00824-87.8887513 Residence Inn Chicago O'Hare, 7101 Chestnut St, Rosemont, ☏ +1-847-375-9000. Home-y hotel with separate kitchens. Rooms from $149. 
• 41.98349-87.8409214 Renaissance Chicago O'Hare Suites Hotel, 8500 W Bryn Mawr Ave, ☏ +1-773-380-9600. Indoor swimming pool. Free 24-hour shuttle service to O'Hare Airport, located by the L stop. Rooms from $179. 
• 41.88631-87.6199215 Radisson Blu Aqua Hotel, Chicago, 221 N Columbus Drive, ☏ +1-312-565-5258, salesaquachicago@radisson.com. Rooms from $259. (updated Aug 2020)
• 42.03721-87.9814716 Sheraton Suites Elk Grove Village, 121 Northwest Point Blvd, Elk Grove Village, ☏ +1-847-290-1600. 253 suites with separate living rooms and bedrooms. Rooms from $159. 
• 42.01018-87.8877217 Wyndham Chicago O'Hare, 1450 E Touhy Ave, Des Plaines, ☏ +1-847-296-8866. About 1.5 miles (2 km) from the airport. Rooms from $105. 

If you're going to spend a lot of money on a hotel and you plan to be in town for more than one night, you'll have a much better time in downtown Chicago. That said, these hotels are big and do a lot of business.

• 41.98853-87.8590518 Chicago Marriott Suites O'Hare, 6155 N River Rd, Rosemont, ☏ +1-847-696-4400, toll-free: +1-866-614-8410. Just five minutes from the airport. Rooms from $269. 
• 41.97764-87.864219 Crowne Plaza Hotel, 5440 N River Rd, Rosemont, ☏ +1-847-671-6350. Giant hotel about 1.5 miles (2 km) from the airport, with copious meeting space. Rooms from $188. 
• 41.9784-87.863120 Doubletree Hotel Chicago O'Hare, 5460 N River Rd, Rosemont, ☏ +1-847-292-9100. About five minutes from the airport. Rooms from $239. 
• 41.99708-87.8820421 Sonesta Chicago O'Hare Airport Rosemont, 10233 W Higgins Rd, Rosemont, ☏ +1-847-954-8600. One mile (2 km) from the airport, this hotel has won the Torch Bearer award for excellent customer service and quality two years in a row Rooms from $95. 
• 41.99727-87.8834522 Sheraton Suites Chicago O'Hare, 6501 N Mannheim Rd, Rosemont, ☏ +1-847-699-6300. Close to O'Hare and the Donald E. Stephens Convention Center in Rosemont. Rooms from $239. 
• 41.98885-87.8613423 The Westin O'Hare, 6100 N River Rd, Rosemont, ☏ +1-847-698-6000. More than 500 pretty rooms with a long list of amenities. Rooms from $329.