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O'Hare Intl

$79+ Cheap flights from Ontario (ONT) to O'Hare Intl (ORD)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 5/1. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — ORD
Apr 21 — Apr 281
Tue 4/21
Tue 4/28
1 adult, Economy
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Find cheap flights from Ontario to O'Hare Intl with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

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3. Compare prices and book

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Cheapflights Tip: The best prices from Ontario to Chicago O'Hare Intl are usually found in August or September, booked 51 days in advance, depart on a Thursday or Wednesday and return on a Tuesday

Cheap flight deals from Ontario to O'Hare Intl

Cheapest flights from Ontario to O'Hare Intl
Explore the most affordable flight options available from Ontario to O'Hare Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 22, 2026.

This CheapOair deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/268:07 am
ONT
-
ORD
1 stop20h 01m
Frontier
Mon 3/308:55 pm
ORD
-
ONT
1 stop18h 33m
Frontier
Deal found 3/20$271
This eDestinos deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure eDestinos is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/910:27 pm
ONT
-
ORD
1 stop11h 23m
Frontier
Mon 4/134:34 pm
ORD
-
ONT
2 stops20h 10m
Frontier
Deal found 3/20$272
This Kiwi.com deal was found by Cheapflights users on 3/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/136:00 am
ONT
-
ORD
1 stop12h 37m
Multiple Airlines
Sun 5/176:05 pm
ORD
-
ONT
2 stops18h 00m
Multiple Airlines
Deal found 3/19$273
This Mytrip deal was found by Cheapflights users on 3/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/116:20 am
ONT
-
ORD
1 stop16h 18m
Frontier
Sat 4/183:23 pm
ORD
-
ONT
1 stop9h 14m
Frontier
Deal found 3/19$276
This Trip.com deal was found by Cheapflights users on 3/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/116:20 am
ONT
-
ORD
1 stop16h 18m
Frontier
Thu 4/165:20 am
ORD
-
ONT
1 stop13h 18m
Frontier
Deal found 3/18$278
This Kiwi.com deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/272:05 pm
ONT
-
ORD
1 stop14h 03m
Frontier
Tue 4/288:58 pm
ORD
-
ONT
1 stop15h 46m
Frontier
Deal found 3/20$279
This Frontier deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/910:27 pm
ONT
-
ORD
1 stop11h 23m
Frontier
Sat 4/115:53 pm
ORD
-
ONT
1 stop8h 03m
Frontier
Deal found 3/20$280
This CheapOair deal was found by Cheapflights users on 3/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/116:20 am
ONT
-
ORD
1 stop16h 18m
Frontier
Wed 4/158:58 pm
ORD
-
ONT
1 stop23h 56m
Frontier
Deal found 3/19$281
This Kiwi.com deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/249:59 pm
ONT
-
ORD
2 stops14h 08m
Frontier
Fri 5/18:58 pm
ORD
-
ONT
1 stop15h 46m
Frontier
Deal found 3/20$283
This Kiwi.com deal was found by Cheapflights users on 3/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/136:00 am
ONT
-
ORD
1 stop12h 37m
Frontier
Sun 5/174:05 pm
ORD
-
ONT
2 stops20h 00m
Frontier
Deal found 3/22$284

Find flight deals from Ontario to O'Hare Intl

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to O'Hare Intl (ORD). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated March 22, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$271
(CheapOair)

One-way from

$79
(Super.com)

Popular in

December

Cheapest in

August

Average price

$462

Good round-trip deal

$354 or less

Good one-way deal

$232 or less
Provider with most accurate pricing for Ontario-Chicago O'Hare Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Ontario-Chicago O'Hare Intl flights.
Search Deals
From Ontario to Chicago O'Hare Intl
Search Deals
One-way flight from Ontario to Chicago O'Hare Intl
Search Deals
Highest demand for flights based on searches. 12% potential increase in price ($56 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($9 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
Search Deals
Price to beat on a round-trip flight from Ontario to Chicago O'Hare Intl.
Search Deals
Price to beat on a one-way flight from Ontario to Chicago O'Hare Intl.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to O'Hare Intl that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 22, 2026.
Use the filters below to find and compare flights from Ontario to Chicago O'Hare Intl Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 4/22

6:00 am-4:56 pm

1 stop8h 56m

Chicago O'Hare Intl

Tue 4/28

8:00 am-2:32 pm

1 stop8h 32m

$357

OntarioChicago

ONT - ORD

ONTORD

Ontario

Fri 4/24

1:43 pm-9:20 pm

1 stop5h 37m

Chicago O'Hare Intl

Mon 4/27

8:05 pm-10:31 pm

Nonstop4h 26m

$363

OntarioChicago

ONT - ORD

ONTORD

Ontario

Thu 4/16

7:08 pm-6:39 am

1 stop9h 31m

Chicago O'Hare Intl

Sat 4/25

6:00 am-2:32 pm

1 stop10h 32m

$377

OntarioChicago

ONT - ORD

ONTORD

Ontario

Thu 6/4

6:30 am-12:45 pm

Nonstop4h 15m

Chicago O'Hare Intl

Wed 6/10

8:13 pm-10:46 pm

Nonstop4h 33m

$397

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 5/6

6:59 pm-5:25 am

1 stop8h 26m

Chicago O'Hare Intl

Wed 5/13

8:09 pm-10:35 pm

Nonstop4h 26m

$407
Quickest round-trip

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 4/15

7:00 am-1:03 pm

Nonstop4h 03m

Chicago O'Hare Intl

Fri 4/17

8:05 pm-10:31 pm

Nonstop4h 26m

$407

OntarioChicago

ONT - ORD

ONTORD

Ontario

Tue 5/26

6:30 am-12:45 pm

Nonstop4h 15m

Chicago O'Hare Intl

Sun 5/31

8:13 pm-10:46 pm

Nonstop4h 33m

$514

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 7/1

5:32 pm-5:02 am

1 stop9h 30m

Chicago O'Hare Intl

Wed 7/8

6:00 am-1:13 pm

1 stop9h 13m

$525

OntarioChicago

ONT - ORD

ONTORD

Ontario

Fri 7/10

7:00 am-4:44 pm

1 stop7h 44m

Chicago O'Hare Intl

Mon 7/13

7:15 am-12:29 pm

1 stop7h 14m

$551

OntarioChicago

ONT - ORD

ONTORD

Ontario

Sun 4/26

7:00 am-1:03 pm

Nonstop4h 03m

Chicago O'Hare Intl

Mon 4/27

8:05 pm-10:31 pm

Nonstop4h 26m

$554

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/17

Showing 1-10 of 23 resultsSorted by cheapest first
1
2
3

Compare providers for flights from Ontario to O'Hare Intl

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ontario to O'Hare Intl in March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
CheapflightsfaresPrice Accuracy2 starsTrust Score*2 stars
CheapfaremartPrice Accuracy-Trust Score*1 star

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Ontario-Chicago O'Hare Intl Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-Chicago O'Hare Intl Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-Chicago O'Hare Intl Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Ontario-Chicago O'Hare Intl Airport flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Ontario-Chicago O'Hare Intl Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Ontario to O'Hare Intl

Have a flexible travel schedule? Discover the best time to fly to O'Hare Intl from Ontario with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Ontario to Chicago O'Hare Intl Airport

How far ahead should I book a flight from Ontario to Chicago O'Hare Intl Airport?

Use this chart to determine the optimal time to book a round-trip flight from Ontario to O'Hare Intl. Price data was last updated on March 13, 2026.

The price you pay for your flight from Ontario to Chicago O'Hare Intl Airport may vary depending on when you book. For the best chance of a lower fare, look to book 51 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

What is the cheapest month to book a flight from Ontario to Chicago O'Hare Intl Airport?

Currently, April is the cheapest month in which you can book a flight from Ontario to Chicago O'Hare Intl Airport (average of $97). Flying from Ontario to Chicago O'Hare Intl Airport in February is currently the most expensive (average of $198). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from ONT to ORD?

Find hourly flight availability from Ontario to O'Hare Intl. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 22, 2026.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Ontario to Chicago O'Hare Intl Airport as you normally would.

Reviews of airlines servicing O'Hare Intl

Get insights into the airlines that provide service to O'Hare Intl. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to O'Hare Intl. Reviews last updated March 22, 2026.
Peruse reviews from past customers who have flown with Southwest,Delta, andUnited Airlines from Ontario to Chicago O'Hare Intl Airport to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,324 reviews

Boarding

8.1

Food

7.0

Overall

8.0

Crew

8.6

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
Southwest
8.0
Very good
4,324 reviews
Southwest
8.0
Very good
4,324 reviews

Boarding

8.1

Food

7.0

Overall

8.0

Crew

8.6

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
Delta
7.9
Good
8,314 reviews
Southwest
8.0
Very good
4,324 reviews

Boarding

8.1

Food

7.0

Overall

8.0

Crew

8.6

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
United Airlines
7.4
Good
9,455 reviews
Southwest
8.0
Very good
4,324 reviews

Boarding

8.1

Food

7.0

Overall

8.0

Crew

8.6

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
American Airlines
7.1
Good
11,489 reviews
Southwest
8.0
Very good
4,324 reviews

Boarding

8.1

Food

7.0

Overall

8.0

Crew

8.6

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
Frontier
5.7
Fair
3,018 reviews
Southwest
8.0
Very good
4,324 reviews

Boarding

8.1

Food

7.0

Overall

8.0

Crew

8.6

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

Related info for your journey

Find useful and relevant information for your journey from Ontario to O'Hare Intl. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from Ontario to Chicago O'Hare Intl?

    Located just 3.1 mi from the city center, Ontario is the airport most travelers will use when flying to Chicago O'Hare Intl from Ontario. Booking flights from Ontario (ONT) to Chicago O'Hare Intl should be relatively easy as there are 0 daily outbound flights to Chicago O'Hare Intl from 5 different airlines.

  • How long is the flight from Ontario to Chicago O'Hare Intl Airport?

    There are many flights that can get you from Ontario to Chicago O'Hare Intl Airport in 5h 37m. Fly via Alaska Airlines or United Airlines to get the fastest option. There are 1695 mi between Ontario and Chicago O'Hare Intl Airport. This flight may include one or multiple stops.

  • What are the cheapest airlines flying from Ontario to Chicago O'Hare Intl Airport round-trip?

    Our cheapest airline available from Ontario to Chicago O'Hare Intl Airport is Frontier. Our recent data shows that you can find tickets from as low as $98 on this airline. Additional options worth looking into are United Airlines and American Airlines, starting at $226 and $246 round-trip. Frontier is currently priced 75% below the average price you’ll pay for this route.

  • What are the cheapest airlines to fly from Ontario to Chicago O'Hare Intl Airport one-way?

    One-way options have recently been found by users for as low as $85 on Frontier. Other airlines that offer cheap prices include Delta from $107 and United Airlines from $113 one-way.

  • What are the cheapest flights from Ontario to Chicago O'Hare Intl Airport?

    On average you can expect to pay $727 for a flight from Ontario to Chicago O'Hare Intl Airport. The cheapest flight overall is $171 while the most popular route, (Ontario - Chicago O'Hare Intl) is currently priced at $160.

  • Can I find deals for flights from Ontario to O'Hare Intl that include hotel bookings?

    Yes. In addition to deals on Ontario to O'Hare Intl flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to O'Hare Intl?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to O'Hare Intl.

  • Can I find deals for business class flights from Ontario to O'Hare Intl?

    Yes. Cheapflights offers flight deals from Ontario to O'Hare Intl by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Ontario to Chicago O'Hare Intl Airport?

    Currently, April is the cheapest month in which you can book a flight from Ontario to Chicago O'Hare Intl Airport (average of $97). Flying from Ontario to Chicago O'Hare Intl Airport in February is currently the most expensive (average of $198). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near Chicago O'Hare Intl Airport?

Book flights to Chicago O'Hare Intl Airport if you plan to visit one of these locations
Schaumburg
Rosemont
Gurnee
Naperville
Lake Geneva
Hoffman Estates
Delavan
Downers Grove
Des Plaines
Elgin
Oak Brook
South Holland
Elk Grove Village
Libertyville
Waukegan
Beloit
Warrenville
Oakbrook Terrace
Bridgeview
Great Lakes

Browse thousands of different options on Cheapflights for your next trip

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Top 5 airlines flying from Ontario to O'Hare Intl

Discover the top 5 airlines that operate flights from Ontario to O'Hare Intl. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 22, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$98Average$241FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$226Average$414FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$246Average$379FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$246Average$518FlexibilityNo cancel feeOn-time71%
DeltaCheapest$256Average$373FlexibilityNo cancel feeOn-timeN/A

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