Cheap flights from Ontario, CA to Chicago, IL

Flights starting at £53. Choose between Frontier Airlines, Allegiant Air, or Spirit Airlines to find the best price.

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Book your trip to arrive at O Hare International, Chicago Midway International, or Chicago Rockford International. The most popular airlines for this route are Frontier Airlines, Allegiant Air, Spirit Airlines, United Airlines, and Alaska Airlines. Ontario and Chicago have 309 direct flights per week.

Weekly direct flights

Discover the top airlines offering direct flights from Ontario to Chicago in the next month. You’ll find the number of daily direct flights per airline in the table.

Weekly direct flights for Mon 25.03 - Sun 31.03

AirlineMon 25.03Tue 26.03Wed 27.03Thu 28.03Fri 29.03Sat 30.03Sun 31.03
111111---

Weekly direct flights for Mon 01.04 - Sun 07.04

AirlineMon 01.04Tue 02.04Wed 03.04Thu 04.04Fri 05.04Sat 06.04Sun 07.04
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Weekly direct flights for Mon 08.04 - Sun 14.04

AirlineMon 08.04Tue 09.04Wed 10.04Thu 11.04Fri 12.04Sat 13.04Sun 14.04
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Weekly direct flights for Mon 15.04 - Sun 21.04

AirlineMon 15.04Tue 16.04Wed 17.04Thu 18.04Fri 19.04Sat 20.04Sun 21.04
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Check-in for a flight from Ontario to Chicago

NameCarrier codeIATA CodePassport needed during bookingOnline check-in available
Frontier AirlinesFFTF9NoOpens 24 days before flight
Closes 1 hours before flight
Allegiant AirAAYG4NoOpens 24 days before flight
Closes 1 hours before flight
Spirit AirlinesNKSNKNoOpens 24 days before flight
Closes 1 hours before flight
United AirlinesUALUAYesNo
Alaska AirlinesASAASNoOpens 24 days before flight
Closes 1 hours before flight

Weather in Chicago

Average Weather

MonthAverage monthly max temperatureAverage monthly min temperature
January0°C-6°C
February0°C-5°C
March5°C0°C
April10°C4°C
May17°C10°C
June22°C16°C
July25°C20°C
August25°C19°C
September22°C16°C
October15°C10°C
November8°C3°C
December2°C-1°C
Hottest Month
25°C
July
Coldest month
-6°C
January
Sunny days
253
days per year
Snow days
17
days per year

14 day forecast

Thursday
21 Mar
3°C-1°C
28 Mar
11°C1°C
Friday
22 Mar
93%
5°C1°C
29 Mar
89%
8°C6°C
Saturday
23 Mar
83%
2°C0°C
30 Mar
79%
5°C2°C
Sunday
24 Mar
7°C0°C
31 Mar
4°C0°C
Monday
25 Mar
83%
11°C5°C
1 Apr
10°C2°C
Tuesday
26 Mar
83%
8°C4°C
2 Apr
78%
10°C6°C
Wednesday
27 Mar
7°C-2°C
3 Apr
6°C-2°C

Frequently asked questions

What are the most popular routes to and from Ontario?
What are the most popular routes to and from Chicago?
What airports are near Ontario?
What airports are near Chicago?
Is it possible to combine flights, buses, and trains in one itinerary when traveling between Ontario and Chicago?
What is Virtual Interlining and how do I use it?
Which airlines fly between Ontario and Chicago?
When's the best time to travel between Ontario and Chicago?
What flights operate between Ontario and Chicago?
How many airports are there near Ontario?
How many airports are there near Chicago?
What time do nonstop (direct) flights between Ontario and Chicago depart?
What time do nonstop (direct) flights between Ontario and Chicago arrive?
What time do flights between Ontario and Chicago depart?
What time do flights between Ontario and Chicago arrive?

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