Cheap Flights from Ontario, CA to Chicago, IL from $101

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On Cheapflightsplus.com you will find 3 direct and 189 connecting flights from Ontario to Chicago. You can compare airfare deals from 4 airlines and multiple travel sites from $101, book and save on cheap plane tickets and last minute offers. Also check out ONT-CHI flight schedule to find best flight time, convenient departure and arrival airports.

Find One-Way and Round-Trip Ontario to Chicago Flight Deals

To find the cheapest one way airline ticket select the date with the lowest price on the calendar below and click «Find Flights». To search for round-trip flight deals click on the link «Check prices for return flights» and select the date of the return flight. Cheapest flights in November: $101 (one-way), $173 (round-trip).

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Best Flights from Ontario to Chicago Today

Take a look at the list of non stop flights and flights with layovers from Ontario to Chicago with the lowest price of $101. The fastest direct flight takes 4h 2m and the fastest connecting – 6h 2m.

Price	Departure	Arrival	Flight Duration	Airline	Flight
from $155 Find flight	07:00 Ontario Ontario Int.	13:02 Chicago O'Hare International	4h 2m	United Airlines	UA356
from $408 Find flight	07:00 Ontario Ontario Int.	13:03 Chicago O'Hare International	4h 3m	United Airlines	UA2649
from $101 Find flight	12:48 Ontario Ontario Int.	22:18 Chicago Midway	7h 30m layover 1h 27m - Houston	Frontier Airlines	F93132 F93282
from $116 Find flight	13:31 Ontario Ontario Int.	23:59 Chicago O'Hare International	8h 28m layover 1h 36m - Seattle	Hawaiian Airlines	HA6289 HA6819
from $163 Find flight	07:10 Ontario Ontario Int.	22:04 Chicago O'Hare International	12h 54m layover 3h 57m - Portland 1h 33m - Seattle	Hawaiian Airlines	HA6286 HA6397 HA6821
from $176 Find flight	07:10 Ontario Ontario Int.	22:04 Chicago O'Hare International	12h 54m layover 3h 57m - Portland 1h 33m - Seattle	Alaska Airlines	AS1058 AS1016 AS941

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*Departure and arrival times - local. Prices indicated for one-way flights. Information updated on September 15, 2025

Flight Schedule Ontario (California) to Chicago (Illinois)

Full flight schedule will help you in detecting at what time planes fly from Ontario to Chicago. You can also specify the concrete flights and airlines on the route and how long the flight actually is. Use the calendar for today, tomorrow or other specific date as some flights are available only on certain days of the week.

Departure	Flight Details	Flight Duration	Price
00:59 — 11:40	00:59 — 04:19 F91500 Frontier Airlines Ontario — Denver 3h 57m stop 08:15 — 11:41 F92210 Frontier Airlines Denver — Chicago	8h 41m including layover	Find flight from$101
00:59 — 23:59	00:59 — 04:19 F91500 Frontier Airlines Ontario — Denver 16h 3m stop 20:31 — 00:10 F93174 Frontier Airlines Denver — Chicago	21h including layover	Find flight from$106
00:59 — 23:53	00:59 — 04:19 F91500 Frontier Airlines Ontario — Denver 16h 2m stop 20:31 — 00:10 F93172 Frontier Airlines Denver — Chicago	20h 54m including layover	Find flight from$117
06:00 — 20:56	06:00 — 07:13 F92232 Frontier Airlines Ontario — Las Vegas 7h 50m stop 15:00 — 21:06 F92146 Frontier Airlines Las Vegas — Chicago	12h 56m including layover	Find flight from$106
06:00 — 14:56	06:00 — 07:10 F92232 Frontier Airlines Ontario — Las Vegas 2h 9m stop 09:19 — 14:56 F92330 Frontier Airlines Las Vegas — Chicago	6h 56m including layover	Find flight from$124
07:00 — 13:02	07:00 — 13:02 UA356 United Airlines Ontario — Chicago	4h 2m	Find flight from$155
07:00 — 13:03	07:00 — 13:03 UA2226 United Airlines Ontario — Chicago	4h 3m	Find flight from$160
07:00 — 13:03	07:00 — 13:03 UA2649 United Airlines Ontario — Chicago	4h 3m	Find flight from$408
11:39 — 22:04	12:00 — 14:38 HA6289 Hawaiian Airlines Ontario — Seattle 1h 40m stop 16:25 — 22:30 HA6821 Hawaiian Airlines Seattle — Chicago	8h 25m including layover	Find flight from$117
11:39 — 22:04	12:00 — 14:38 AS1111 Alaska Airlines Ontario — Seattle 1h 40m stop 16:25 — 22:30 AS941 Alaska Airlines Seattle — Chicago	8h 25m including layover	Find flight from$124
12:48 — 22:18	12:48 — 18:19 F93132 Frontier Airlines Ontario — Houston 1h 27m stop 19:45 — 22:23 F93282 Frontier Airlines Houston — Chicago	7h 30m including layover	Find flight from$101
13:31 — 23:59	12:00 — 14:38 HA6289 Hawaiian Airlines Ontario — Seattle 1h 36m stop 17:54 — 23:59 HA6819 Hawaiian Airlines Seattle — Chicago	8h 28m including layover	Find flight from$116
13:31 — 23:59	12:00 — 14:38 AS1111 Alaska Airlines Ontario — Seattle 1h 36m stop 17:54 — 23:59 AS538 Alaska Airlines Seattle — Chicago	8h 28m including layover	Find flight from$124
17:14 — 21:06 +1 day	17:14 — 18:28 F91358 Frontier Airlines Ontario — Las Vegas 20h 32m stop 15:00 — 21:06 F92146 Frontier Airlines Las Vegas — Chicago	25h 52m including layover	Find flight from$130
17:21 — 00:10 +2 days	17:21 — 20:44 F92908 Frontier Airlines Ontario — Denver 23h 47m stop 20:31 — 00:10 F93172 Frontier Airlines Denver — Chicago	28h 49m including layover	Find flight from$106

Departure	Arrival	Flight Details	Flight Time	Price
		stop stop	including layover	Find flight from$

*Departure and arrival times - local. Updated on September 15, 2025

Flight Information

Below we will explain in detail what the flights cost on the destination from Ontario to Chicago depends on and how to choose the most interesting flight option for you.

Distance between Ontario and Chicago is 2751 miles. Time difference between the cities is 2h. Airplanes depart 00:59 to 20:09 from 2 Ontario airports and arrive 00:59 to 20:09 to 7 Chicago airports. Average flight time is 4h 3m.

The fastest flight 4h 2m
Average flight time 4h 3m
The earliest flight 00:59
The latest flight 20:09
Distance 1710 ml

The cheapest months to travel to Chicago are july (from 101 $), october (from 116 $), september (from 117 $).

The most expensive months are february (from 322 $), december (from 260 $), august (from 130 $).

What is the lowest airfare Ontario to Chicago?

The cheapest plane ticket found by our users is $101. This airfare is for economy class on one-way F93132 flight by Frontier Airlines for July 4, 2025 which leaves Ontario Int. in Ontario at 12:48 am and arrives at Chicago Midway at 22:18.

Economy class

$101

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Business class

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First class

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Popular Airlines on the Route

The flight Ontario — Chicago is served by 4 regular airlines and 1 low-cost airline. Most of the flights on this route are operated by Alaska Airlines - 45 departures per week at the price of from $ 124 . And the most expensive tickets are offered by Alaska Airlines airline - from $ 6857.

Direct flights

There are 3 nonstop flights on the route. The fastest direct flight is UA356 by United Airlines takes 4h 2m and the cheapest is F93132 by Frontier Airlines for $155.

UA - United Airlines

from $155

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Connecting Flights

There are 189 flights with layovers on the route. The fastest connecting flight is UA2446 by United Airlines takes 6h 2m and the cheapest is F93132 by Frontier Airlines for $101.

AS - Alaska Airlines

from $124

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F9 - Frontier Airlines

from $101

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HA - Hawaiian Airlines

from $116

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UA - United Airlines

from $164

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Airports

You can fly from Ontario to Chicago from 2 airports (Ontario Int., International Heliport).

Ontario airports

Ontario Int.-ONT

from $101
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International Heliport-JIO

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Chicago airports

O'Hare International-ORD

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Midway-MDW

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Dupage County-DPA

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Chicago FSS-CHI

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Merrill C Meigs (closed)-CGX

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Pal-Waukee-PWK

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Chicago NAS-NOH

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Airplanes

There are flights to Chicago from Ontario by 4 airlines that use 0 aircraft brands. They range from huge modern airplanes to small-sized.

Top Domestic Destinations from Ontario

You may also consider searching for discounted plane tickets to some other popular places from Ontario within United States.

Ontario — Phoenix

from $56

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Ontario — Denver

from $65

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Ontario — Austin

from $67

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Ontario — Miami

from $62

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Ontario — Tucson

from $80

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Ontario — Las Vegas

from $63

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Ontario — Seattle

from $65

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Ontario — Boise

from $70

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Ontario — Chicago

from $78

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Ontario — Philadelphia

from $62

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Top International Destinations from Ontario

Our state-of-the art metasearch will definitely provide you with the best airfare on international flights. We’re proud to partner with many reliable travel suppliers located outside the US what gives us an opportunity to offer the most competitive prices on far destinations.

Ontario — London

from $62

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Ontario — San Jose

from $61

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Ontario — Guadalajara

from $70

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Ontario — Cancun

from $74

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How to book a plane ticket yourself?

Fill in the search parameters — cities of departure and destination, departure and return dates and click «Find flights»
Select the best flight that you like. Please, check the airports of departure and arrival. Select the best fare, but pay attention to the following flight details - airports of departure and arrival, flight duration and layovers. Please use filters and sort to find the best flight.
Click «Buy» when you are ready — our system will redirect you to the site that sells the selected flight ticket.
Fill in all passenger and payment information — passport and contact information, please double check all passengers’ names and make a payment for your itinerary.
That's it — you will receive an email with your e-ticket usually within 10 minutes after your flight is confirmed. Please, print the e-ticket and have it with you at the airport. You would need to have only a passport and/or a required form of ID to travel. Please, check your Visa requirements if you travel outside of the United States or Canada.
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