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.

$117 CHEAP FLIGHTS from Illinois to Ontario

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Cheap Flights from Illinois to Ontario

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

Tue, Dec 8 - Tue, Dec 15

7:25 am - 10:45 amORD Chicago O'Hare Intl-ONT Ontario

29h 20m1 stop Denver Intl

6:00 am - 12:54 amONT Ontario-ORD Chicago O'Hare Intl

16h 54m1 stop Denver Intl

$145Frontier

Wed, Dec 9 - Tue, Dec 15

7:25 am - 10:17 pmORD Chicago O'Hare Intl-ONT Ontario

16h 52m1 stop Denver Intl

6:00 am - 12:54 amONT Ontario-ORD Chicago O'Hare Intl

16h 54m1 stop Denver Intl

$160Frontier

Sun, Jan 10 - Wed, Jan 13

9:29 pm - 8:05 amPIA Greater Peoria-ONT Ontario

12h 36m1 stop Las Vegas Harry Reid Intl

9:22 pm - 8:36 pmONT Ontario-PIA Greater Peoria

21h 14m1 stop Las Vegas Harry Reid Intl

$210Multiple Airlines

Thu, Dec 10 - Tue, Dec 15

9:00 am - 4:05 pmORD Chicago O'Hare Intl-ONT Ontario

9h 05m1 stop Seattle/Tacoma Intl

11:00 am - 5:01 amONT Ontario-ORD Chicago O'Hare Intl

16h 01m1 stop Las Vegas Harry Reid Intl

$234Multiple Airlines

Sat, Feb 6 - Wed, Feb 10

4:10 pm - 6:50 pmORD Chicago O'Hare Intl-ONT Ontario

4h 40mnonstop

9:45 am - 8:40 pmONT Ontario-ORD Chicago O'Hare Intl

8h 55m1 stop San Francisco

$249United Airlines

Thu, Dec 3 - Thu, Dec 10

12:40 pm - 8:38 pmORD Chicago O'Hare Intl-ONT Ontario

9h 58m1 stop San Francisco

7:00 am - 1:11 pmONT Ontario-ORD Chicago O'Hare Intl

4h 11mnonstop

$249United Airlines

Wed, Feb 17 - Sat, Feb 20

6:00 am - 11:54 amMDW Chicago Midway-ONT Ontario

7h 54m1 stop Atlanta Hartsfield-Jackson

7:05 am - 4:36 pmONT Ontario-MDW Chicago Midway

7h 31m1 stop Atlanta Hartsfield-Jackson

$259Delta

Wed, Dec 9 - Mon, Dec 14

1:02 pm - 8:58 pmMDW Chicago Midway-ONT Ontario

9h 56m1 stop Atlanta Hartsfield-Jackson

12:20 pm - 10:54 pmONT Ontario-MDW Chicago Midway

8h 34m1 stop Atlanta Hartsfield-Jackson

$259Delta

Sat, Dec 5 - Sat, Dec 12

10:25 am - 12:45 pmMDW Chicago Midway-ONT Ontario

4h 20mnonstop

8:20 am - 2:05 pmONT Ontario-MDW Chicago Midway

3h 45mnonstop

$261Southwest

Fri, Feb 5 - Tue, Feb 9

9:30 pm - 11:55 pmMDW Chicago Midway-ONT Ontario

4h 25mnonstop

6:30 am - 12:25 pmONT Ontario-MDW Chicago Midway

3h 55mnonstop

$269Southwest

Recent last minute flight deals from Illinois to Ontario

Sat, Nov 14 - Thu, Nov 26

10:29 am - 4:38 pmORD Chicago O'Hare Intl-ONT Ontario

8h 09m1 stop Dallas/Fort Worth

6:08 pm - 7:46 amONT Ontario-ORD Chicago O'Hare Intl

11h 38m1 stop Dallas/Fort Worth

$224Frontier

Mon, Nov 16 - Fri, Nov 20

5:15 pm - 9:40 amORD Chicago O'Hare Intl-ONT Ontario

18h 25m1 stop Las Vegas Harry Reid Intl

2:01 pm - 5:10 amONT Ontario-ORD Chicago O'Hare Intl

13h 09m1 stop Las Vegas Harry Reid Intl

$246Frontier

Thu, Nov 12 - Tue, Nov 17

4:15 pm - 6:47 pmORD Chicago O'Hare Intl-ONT Ontario

4h 32mnonstop

9:25 am - 6:49 pmONT Ontario-ORD Chicago O'Hare Intl

7h 24m1 stop San Francisco

$337United Airlines

Fri, Nov 13 - Fri, Nov 27

2:22 pm - 9:40 pmORD Chicago O'Hare Intl-ONT Ontario

9h 18m1 stop Houston George Bush Intcntl

7:00 am - 1:04 pmONT Ontario-ORD Chicago O'Hare Intl

4h 04mnonstop

$337United Airlines

Sat, Nov 14 - Mon, Nov 16

10:29 am - 4:38 pmORD Chicago O'Hare Intl-ONT Ontario

8h 09m1 stop Dallas/Fort Worth

7:13 pm - 5:40 amONT Ontario-ORD Chicago O'Hare Intl

8h 27m1 stop Seattle/Tacoma Intl

$343Multiple Airlines

Mon, Nov 16 - Fri, Nov 20

1:30 pm - 9:57 pmORD Chicago O'Hare Intl-ONT Ontario

10h 27m1 stop Atlanta Hartsfield-Jackson

1:15 pm - 9:47 pmONT Ontario-ORD Chicago O'Hare Intl

6h 32m1 stop Salt Lake City

$347Delta

Mon, Nov 16 - Sat, Nov 21

1:30 pm - 9:57 pmORD Chicago O'Hare Intl-ONT Ontario

10h 27m1 stop Atlanta Hartsfield-Jackson

7:05 am - 7:05 pmONT Ontario-ORD Chicago O'Hare Intl

10h 00m1 stop Atlanta Hartsfield-Jackson

$347Delta

Thu, Nov 12 - Tue, Nov 17

10:15 am - 4:55 pmMDW Chicago Midway-ONT Ontario

8h 40m1 stop Sacramento Intl

10:05 am - 7:35 pmONT Ontario-MDW Chicago Midway

7h 30m1 stop Denver Intl

$347Southwest

Wed, Nov 11 - Tue, Nov 17

6:05 am - 10:10 amMDW Chicago Midway-ONT Ontario

6h 05m1 stop Denver Intl

6:55 pm - 5:55 amONT Ontario-MDW Chicago Midway

9h 00m1 stop Oakland

$347Southwest

Thu, Nov 12 - Fri, Nov 13

11:15 am - 7:08 pmORD Chicago O'Hare Intl-ONT Ontario

9h 53m2 stops Cape Girardeau Dallas/Fort Worth

8:35 pm - 5:13 amONT Ontario-ORD Chicago O'Hare Intl

6h 38m1 stop Las Vegas Harry Reid Intl

$402Multiple Airlines

Useful Info

Low season	January
High season	December
Cheapest flight	$117

Best time to beat the crowds with an average 9% drop in price.

Most popular time to fly with an average 1% increase in price.

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.