There are two passenger terminals at Ontario International Airport (ONT): Terminal 2 and Terminal 4. The third building at the airport is the International Arrivals Facility, which has two arrival gates only for customs clearance. There is also a one-way loop road (East Airport Drive) and a covered walkway between the terminals. Terminal 2 has 12 gates (201–212); Terminal 4 has 14 gates (401–414). Knowing the right terminal for your flight, as well as the system of the loop road, is the key piece of information that any ONT map can provide you with before entering the airport.
This guide gives you detailed information about ONT terminals, parking, ground transport, and security measures.
ONT Airport Facts
- IATA code: ONT | ICAO code: KONT
- Address: 2900 East Airport Drive, Ontario, CA – approximately 35–38 miles east of downtown Los Angeles
- Operator: Ontario International Airport Authority
- Terminals: Terminal 2, Terminal 4, and the International Arrivals Facility (IAF)
- Annual traffic volume: estimated at 7.1 million (2025)
- Non-stop connections: up to 90 non-stop flights to over 30 destinations in the USA, Mexico, Central America, and Taiwan
- Commute time from Los Angeles: usually 45–60 minutes by I-10, depending on traffic
Terminal 2: Plan, Gates & Airlines Operating in Terminal 2
Terminal 2 covers 265,000 square feet and has 12 gates (201–212). This is normally the international part of the airport and serves Alaska Airlines, Avianca, China Airlines, Delta Air Lines, Frontier, JetBlue, United Airlines, and Volaris. The international departures with airlines such as Avianca, China Airlines, and Volaris depart from Terminal 2 gates, although the arrival of international passengers happens separately in the IAF.
In Terminal 2, you will find:
- The Aspire Lounge adjacent to Gate 210
- 3Sixty Duty Free – the first West Coast airport to house that retailer
- Restaurants such as Wolfgang Puck Pizza, Cross Grain Brewhouse, Harvest & Grounds, Brewery X, and Starbucks
- A USO Lounge in the west wing
- Two baggage claim carousels in the lower level
- A TSA checkpoint with PreCheck and CLEAR lanes in the upper level
Terminal 4: Layout, Gates, and Airlines
While the Terminal 4 building has the same 265,000 square feet of space as Terminal 2, it has 14 gates (401–414), making it the larger terminal by number of gates. The majority of ONT’s domestic flights come from this terminal, which is dominated by Southwest Airlines along with American Airlines and Hawaiian Airlines.
Key features of Terminal 4 are:
- The Aspire Lounge located near Gate 410
- Restaurants such as Rock & Brews, Brewery X, Chick-fil-A, Wahoo’s Fish Taco, Mi Casa Cantina, Dunkin’ and Einstein Bros. Bagels
- A satellite California Science Center exhibit
- Three baggage claim carousels in the lower level
- Its own TSA checkpoint, currently undergoing expansion from 4 to 6 lanes, expected to be finished by fall 2026
Since the expansion at the terminal is still underway, there are temporary closures of the family bathrooms in both Terminal 2 and Terminal 4 located near the security checkpoint until construction is completed.
International Arrivals Facility (IAF)
The IAF is a standalone facility apart from the two main terminals, featuring two arrival-only gates. The IAF has U.S. Customs and Border Protection and the Federal Inspection Service. Passengers arriving with Avianca, China Airlines, Starlux, and Volaris use the IAF upon their arrival. Additionally, there is a Global Entry Enrollment Center located there. Both domestic and international flights depart from Terminal 2 or Terminal 4; however, the IAF is used exclusively for processing international arrivals prior to entering the main terminal complex.
Traveling Between Terminals
Terminal 2 and Terminal 4 are linked by a covered walkway for pedestrians, which means that switching terminals is an easy process once you get through security on the landside. There is also a courtesy shuttle operating between the two terminals as well as to the rental car center at about every 5 to 20 minute intervals during 24 hours a day, except from 12:30 a.m. until 3:00 a.m., when service is reduced.
Driving and Terminal Location
ONT’s terminals are located on a one-way loop known as East Airport Drive, with Terminal 2 arriving first for cars approaching from the airport entrance and Terminal 4 later on the loop. To reach the airport from I-10, take the Archibald Avenue exit southbound to the airport entrance, and then take East Airport Drive to reach the terminal loop.
At ONT Airport , the biggest navigational error made by drivers is not getting to the Terminal 4 curb. If you remain too far left when leaving Terminal 2 complex, you will find yourself in the lanes where cars park or rent vehicles, hence missing out on Terminal 4 drop-off. To avoid this problem, if your destination is Terminal 4, make sure that you remain in the center-right lanes when leaving Terminal 2.
Parking at ONT
ONT has a variety of parking options available at various prices and distances:
- Parking Lots 2 and 4 – closest to their respective terminals; $30/day general, $35/day premium
- Parking Lot 3 – located between both terminals; $25/day
- Economy Parking Lots 5 and 6 – $20/day and include free shuttle transportation to the terminals (a distance of about 500 feet from the corner of Lot 5)\
- Reservations booked in advance on flyontario.com can help save around 10% of drive-up costs
Ground Transportation
Apart from being able to drive, ONT is linked to the surrounding area by:
- Rideshare and taxis – picked up from designated curb islands, not from general arrivals curb
- OmniTrans Route 61 – a public bus connecting ONT with the regional transit system
- Rental car center – accessed using the free shuttle from either terminal
- A Cell Phone Waiting Lot for those picking up passengers arriving at ONT without parking
Security, TSA PreCheck, and CLEAR
There is a separate TSA security checkpoint at each terminal that does not share a common security area with Terminal 2 and Terminal 4. Both of the terminals have the TSA PreCheck and CLEAR lanes, located in the proximity of escalators. Security check-in times average below 20 minutes when it is not a peak period; otherwise, it can reach up to 30 minutes or longer. The security checkpoint at Terminal 4 is undergoing expansion to increase the number of lanes from four to six by fall 2026.
Conclusion
As ONT operates from two separate terminals that have their own security checkpoints, the most important thing to find out prior to going to the airport is which terminal your airline operates from: Terminal 2 or Terminal 4. Arriving at the wrong terminal would mean additional walking, shuttling, or driving.
Ontario International Airport has two passenger terminals – Terminal 2 and Terminal 4 – and one International Arrivals Facility that handles arrivals from international flights.
Terminal 2 at ONT handles Alaska Airlines, Avianca, China Airlines, Delta Air Lines, Frontier, JetBlue, United Airlines, and Volaris.
Terminal 4 at ONT handles American Airlines, Hawaiian Airlines, and Southwest Airlines, with Southwest being the main airline in that terminal.
Yes, passengers can access both terminals through a covered pedestrian walkway that is located on the landside, and there is also a shuttle service between both terminals and the rental car center.
The Economy Lots 5 and 6 have the lowest daily fees at $20 per day, with a complimentary shuttle service to the terminal. Making an online reservation will provide a 10% discount.