How does KAYAK find such low prices on flights from Illinois to Ontario?

KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Illinois to Ontario. Visit our flight page for the latest deals!>/a>

How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Illinois to Ontario?

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Ontario from Illinois is likely to change within 7 days, so travelers know whether to wait or book now. Visit our flight page for the latest deals!>/a>

What is the Hacker Fare option on flights from Illinois to Ontario?

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Ontario with an airline and back to Illinois with another airline. Visit our flight page for the latest deals!>/a>

What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Illinois to Ontario?

Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Ontario from Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best. Visit our flight page for the latest deals!>/a>

$84 CHEAP FLIGHTS from Illinois to Ontario

ONT

KAYAK searches hundreds of travel sites at once for deals on flights to Ontario

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Cheap Flights from Illinois to Ontario

Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Illinois to Ontario that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.

Discover the best prices for you by selecting your travel dates on KAYAK.

Round-trip

One-way

Last minute

Direct

Recent round-trip flight deals from Illinois to Ontario

Wed, Sep 3 - Wed, Sep 10

7:59 pm - 10:30 pmORD-ONT

4h 31mnonstop

7:00 am - 1:03 pmONT-ORD

4h 03mnonstop

$173United Airlines

Find Deal

Fri, Oct 10 - Wed, Oct 22

7:59 pm - 10:30 pmORD-ONT

4h 31mnonstop

7:02 am - 1:05 pmONT-ORD

4h 03mnonstop

$190United Airlines

Find Deal

Tue, Nov 11 - Sat, Nov 15

5:30 am - 9:40 amMDW-ONT

6h 10m1 stop

7:00 am - 4:40 pmONT-MDW

7h 40m1 stop

$192Southwest

Find Deal

Wed, Sep 3 - Wed, Sep 10

6:00 am - 11:55 amORD-ONT

7h 55m1 stop

1:10 pm - 9:05 pmONT-ORD

5h 55m1 stop

$193American Airlines

Find Deal

Tue, Sep 16 - Tue, Sep 30

5:18 am - 11:57 amSTL-ONT

8h 39m1 stop

10:35 pm - 9:16 amONT-STL

8h 41m1 stop

$195American Airlines

Find Deal

Wed, Sep 3 - Wed, Sep 10

6:20 am - 2:12 pmORD-ONT

9h 52m1 stop

11:39 am - 12:03 amONT-ORD

10h 24m1 stop

$203Alaska Airlines

Find Deal

Tue, Aug 26 - Mon, Sep 1

7:54 pm - 11:50 pmSTL-ONT

5h 56m1 stop

12:59 am - 9:11 amONT-STL

6h 12m1 stop

$210Frontier

Find Deal

Thu, Sep 11 - Tue, Sep 16

8:00 am - 2:12 pmORD-ONT

8h 12m1 stop

11:39 am - 12:03 amONT-ORD

10h 24m1 stop

$214Alaska Airlines

Find Deal

Wed, Oct 22 - Fri, Oct 24

7:52 pm - 11:50 pmSTL-ONT

5h 58m1 stop

12:59 am - 9:07 amONT-STL

6h 08m1 stop

$216Frontier

Find Deal

Tue, Dec 9 - Sat, Dec 13

10:15 am - 7:15 pmSTL-ONT

11h 00m2 stops

9:10 am - 7:45 pmONT-STL

8h 35m2 stops

$276Southwest

Find Deal

Useful Info

Low season	February
High season	August
Cheapest flight	$84

Best time to beat the crowds with an average 5% drop in price.

Most popular time to fly and prices are also 11% lower on average.

Flight from Chicago O'Hare Airport to Ontario

How does KAYAK find such low prices on flights from Illinois to Ontario?
KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Illinois to Ontario.
How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Illinois to Ontario?
KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Ontario from Illinois is likely to change within 7 days, so travelers know whether to wait or book now.
What is the Hacker Fare option on flights from Illinois to Ontario?
Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Ontario with an airline and back to Illinois with another airline.
What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Illinois to Ontario?
Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Ontario from Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Everything you need to know for your flight to Ontario

Airports

Cabin class

Complete your trip

Direct Flights

Flights to other cities

Origins

Other airports

Return flight deals

Information on the airport you'll fly into in Ontario

Ontario (ONT)

Not what you’re looking for? Find thousands of other hotels, flights, car rentals and package deals with KAYAK.

ONT

$84 Find Cheap Flights from Illinois to Ontario

KAYAK searches hundreds of travel sites at once for deals on flights to Ontario

Cheap Flights from Illinois to Ontario

Recent round-trip flight deals from Illinois to Ontario

Recent one-way flight deals from Illinois to Ontario

Recent last minute flight deals from Illinois to Ontario

Recent direct flight deals from Illinois to Ontario

Good to know

FAQs for booking flights from Illinois to Ontario

How does KAYAK find such low prices on flights from Illinois to Ontario?

KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Illinois to Ontario.

How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Illinois to Ontario?

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Ontario from Illinois is likely to change within 7 days, so travelers know whether to wait or book now.

What is the Hacker Fare option on flights from Illinois to Ontario?

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Ontario with an airline and back to Illinois with another airline.

What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Illinois to Ontario?

Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Ontario from Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Everything you need to know for your flight to Ontario

Information on the airport you'll fly into in Ontario

Cabin class types available on flights to Illinois

Complete your trip to Ontario with a hotel stay or car rental

Find direct flights for Ontario

Flights to other popular destinations

Flights from domestic origins to Ontario

Choose which airport to fly into in Ontario

Find deals for your return flight