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O'Hare Intl

$62+ 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 11/1. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — ORD
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
1 adult, Economy
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Cheapflights Tip: The best prices from Ontario to Chicago O'Hare Intl are usually found in September or October, booked 45 days in advance, depart on a Thursday or Monday and return on a Tuesday

Cheap 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 September 11, 2025.

Round-trip from

$179
(United Airlines)

One-way from

$62
(Trip.com)

Popular in

November

Cheapest in

September

Average price

$242

Good round-trip deal

$358 or less

Good one-way deal

$196 or less
From Ontario to Chicago O'Hare Intl
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One-way flight from Ontario to Chicago O'Hare Intl
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Highest demand for flights based on searches. 11% potential increase in price ($46 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($14 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Price to beat on a round-trip flight from Ontario to Chicago O'Hare Intl.
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Price to beat on a one-way flight from Ontario to Chicago O'Hare Intl.
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Find 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 September 11, 2025.

This United Airlines deal was found by Cheapflights users on 9/11. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/17:02 amONT - ORD
Nonstop4h 03mUnited Airlines
Mon 10/67:59 pmORD - ONT
Nonstop4h 31mUnited Airlines
Deal found 9/11$179
This CheapOair deal was found by Cheapflights users on 9/11. 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.
Fri 10/1012:32 pmONT - ORD
1 stop10h 12mFrontier
Sun 10/125:25 amORD - ONT
1 stop28h 24mFrontier
Deal found 9/11$180
This Booking.com deal was found by Cheapflights users on 9/11. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/258:59 pmONT - ORD
1 stop25h 00mFrontier
Sat 9/278:25 amORD - ONT
1 stop24h 58mFrontier
Deal found 9/11$181
This Frontier deal was found by Cheapflights users on 9/11. 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.
Sun 10/1212:49 pmONT - ORD
1 stop9h 37mFrontier
Sun 10/199:54 pmORD - ONT
1 stop11h 53mFrontier
Deal found 9/11$182
This CheapOair deal was found by Cheapflights users on 9/11. 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.
Wed 10/156:53 amONT - ORD
1 stop15h 00mFrontier
Mon 10/206:00 amORD - ONT
1 stop12h 28mFrontier
Deal found 9/11$184
This Booking.com deal was found by Cheapflights users on 9/11. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/248:00 amONT - ORD
1 stop25h 48mFrontier
Sat 9/278:25 amORD - ONT
1 stop13h 29mFrontier
Deal found 9/11$186
This Booking.com deal was found by Cheapflights users on 9/11. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/117:04 amONT - ORD
1 stop14h 49mFrontier
Sat 10/187:05 amORD - ONT
1 stop18h 45mFrontier
Deal found 9/11$188
This CheapOair deal was found by Cheapflights users on 9/11. 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.
Tue 9/308:59 pmONT - ORD
1 stop22h 29mFrontier
Sun 10/129:54 pmORD - ONT
1 stop11h 53mFrontier
Deal found 9/11$189
This Mytrip deal was found by Cheapflights users on 9/11. 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.
Thu 9/258:59 pmONT - ORD
1 stop10h 38mFrontier
Sun 9/288:50 amORD - ONT
1 stop8h 34mFrontier
Deal found 9/11$190
This CheapOair deal was found by Cheapflights users on 9/11. 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.
Tue 9/238:59 pmONT - ORD
1 stop22h 29mFrontier
Wed 10/17:20 amORD - ONT
1 stop26h 03mFrontier
Deal found 9/11$191
This Booking.com deal was found by Cheapflights users on 9/11. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/64:08 pmONT - ORD
1 stop5h 51mFrontier
Thu 10/91:14 pmORD - ONT
1 stop29h 14mFrontier
Deal found 9/11$193

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 September 11, 2025.
Use the filters below to find and compare flights from Ontario to Chicago O'Hare Intl Airport that are best for you.

Fly from

Ontario

Fly to

O'Hare Intl

Route

Depart

Return

Price

OntarioChicago

ONT - ORD

ONTORD

Ontario

Tue 10/21

7:02 am-1:05 pm

Nonstop4h 03m

Chicago O'Hare Intl

Wed 10/22

7:59 pm-10:30 pm

Nonstop4h 31m

$179

OntarioChicago

ONT - ORD

ONTORD

Ontario

Fri 10/17

12:32 pm-12:44 am

1 stop10h 12m

Chicago O'Hare Intl

Sun 10/19

9:54 pm-7:47 am

1 stop11h 53m

$188

OntarioChicago

ONT - ORD

ONTORD

Ontario

Sat 10/18

7:02 am-1:05 pm

Nonstop4h 03m

Chicago O'Hare Intl

Mon 10/20

7:59 pm-10:30 pm

Nonstop4h 31m

$188

OntarioChicago

ONT - ORD

ONTORD

Ontario

Fri 10/24

11:53 am-12:59 am

1 stop11h 06m

Chicago O'Hare Intl

Sun 10/26

9:54 pm-7:47 am

1 stop11h 53m

$192

OntarioChicago

ONT - ORD

ONTORD

Ontario

Thu 10/9

6:54 pm-8:54 pm

1 stop24h 00m

Chicago O'Hare Intl

Mon 10/13

9:54 pm-8:42 pm

1 stop24h 48m

$194

OntarioChicago

ONT - ORD

ONTORD

Ontario

Sat 10/25

6:36 pm-5:13 am

1 stop8h 37m

Chicago O'Hare Intl

Mon 10/27

4:00 pm-6:36 pm

Nonstop4h 36m

$205

OntarioChicago

ONT - ORD

ONTORD

Ontario

Sat 1/10

11:30 am-11:59 pm

1 stop10h 29m

Chicago O'Hare Intl

Sat 1/17

7:45 am-3:12 pm

1 stop9h 27m

$214

OntarioChicago

ONT - ORD

ONTORD

Ontario

Sat 1/10

11:30 am-11:59 pm

1 stop10h 29m

Chicago O'Hare Intl

Mon 1/12

7:45 am-3:12 pm

1 stop9h 27m

$214

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 10/1

7:02 am-1:05 pm

Nonstop4h 03m

Chicago O'Hare Intl

Tue 10/7

7:59 pm-10:30 pm

Nonstop4h 31m

$253

OntarioChicago

ONT - ORD

ONTORD

Ontario

Sat 1/10

7:00 am-1:03 pm

Nonstop4h 03m

Chicago O'Hare Intl

Sat 1/17

7:55 pm-10:26 pm

Nonstop4h 31m

$253

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/11

Showing 1-10 of 23 results
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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 August 29, 2025.

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 45 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, August is the cheapest month in which you can book a flight from Ontario to Chicago O'Hare Intl Airport (average of $245). Flying from Ontario to Chicago O'Hare Intl Airport in March is currently the most expensive (average of $321). 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 September 11, 2025.

It’s typically best to fly out from Ontario to Chicago O'Hare Intl Airport in the afternoon. Doing so could potentially save you 60% on the flight price compared to flying in the evening, which is usually more expensive.

What is the cheapest day to fly from Ontario to Chicago O'Hare Intl Airport?

Use this chart to determine the cheapest time to fly round-trip from Ontario to O'Hare Intl. Price data was last updated on September 7, 2025.

Travelers seeking maximum savings on their Ontario to Chicago O'Hare Intl Airport flight should consider departing on Wednesday evenings when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

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 September 11, 2025.
Peruse reviews from past customers who have flown with Southwest, Delta, and United 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
4,248 reviews

Entertainment

7.5

Crew

8.6

Boarding

8.1

Comfort

8.0

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Southwest
8.0
Very good
4,248 reviews
Southwest
8.0
Very good
4,248 reviews

Entertainment

7.5

Crew

8.6

Boarding

8.1

Comfort

8.0

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Delta
8.0
Very good
7,960 reviews
Southwest
8.0
Very good
4,248 reviews

Entertainment

7.5

Crew

8.6

Boarding

8.1

Comfort

8.0

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
United Airlines
7.4
Good
8,937 reviews
Southwest
8.0
Very good
4,248 reviews

Entertainment

7.5

Crew

8.6

Boarding

8.1

Comfort

8.0

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
American Airlines
7.2
Good
10,000 reviews
Southwest
8.0
Very good
4,248 reviews

Entertainment

7.5

Crew

8.6

Boarding

8.1

Comfort

8.0

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Frontier
5.8
Fair
3,177 reviews
Southwest
8.0
Very good
4,248 reviews

Entertainment

7.5

Crew

8.6

Boarding

8.1

Comfort

8.0

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.

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 6 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 4h 03m. Fly via United Airlines or Frontier 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 Spirit Airlines. Our recent data shows that you can find tickets from as low as $99 on this airline. Additional options worth looking into are Frontier and United Airlines, starting at $108 and $227 round-trip. Spirit Airlines is currently priced 72% below the average price you’ll pay for this route.

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

    On average you can expect to pay $752 for a flight from Ontario to Chicago O'Hare Intl Airport. The cheapest flight overall is $156 while the most popular route, (Ontario - Chicago O'Hare Intl) is currently priced at $149.

  • 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, August is the cheapest month in which you can book a flight from Ontario to Chicago O'Hare Intl Airport (average of $245). Flying from Ontario to Chicago O'Hare Intl Airport in March is currently the most expensive (average of $321). 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
Skokie
Gurnee
Hoffman Estates
Des Plaines
Elgin
Arlington Heights
Beloit
Racine
Rockford
Orland Park
Oak Brook
Downers Grove
Naperville
Elk Grove Village
Evanston
Merrillville
Bridgeview
Warrenville

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Alternative routes for Ontario to O'Hare Intl

See prices for flight routes from nearby airports that may be better suited for you.
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Top 6 airlines flying from Ontario to O'Hare Intl

Discover the top 6 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 September 11, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$99Average$145FlexibilityNo cancel feeOn-time65%
FrontierCheapest$108Average$168FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$227Average$385FlexibilityNo cancel feeOn-time69%
DeltaCheapest$241Average$353FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$246Average$508FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$251Average$463FlexibilityNo cancel feeOn-time63%

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