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O'Hare Intl

$77+ 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 10/21. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — ORD
Aug 2 — Aug 91
Sat 8/2
Sat 8/9
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 80 days in advance, depart on a Monday or Thursday and return on a Wednesday

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 July 28, 2025.

Round-trip from

$259
(Booking.com)

One-way from

$77
(Trip.com)

Popular in

November

Cheapest in

September

Average price

$382

Good round-trip deal

$418 or less

Good one-way deal

$193 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 July 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 July 28, 2025.

This Booking.com deal was found by Cheapflights users on 7/27. 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.
Sun 8/312:59 amONT - ORD
1 stop21h 33mFrontier
Fri 8/89:56 pmORD - ONT
1 stop20h 24mFrontier
Deal found 7/27$259
This American Airlines deal was found by Cheapflights users on 7/27. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/266:17 amONT - ORD
1 stop10h 00mAmerican Airlines
Sat 8/308:00 amORD - ONT
1 stop10h 24mAmerican Airlines
Deal found 7/27$274
This United Airlines deal was found by Cheapflights users on 7/26. 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 9/37:00 amONT - ORD
Nonstop4h 03mUnited Airlines
Sat 9/137:59 pmORD - ONT
Nonstop4h 31mUnited Airlines
Deal found 7/26$317
This Alaska Airlines deal was found by Cheapflights users on 7/27. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/155:45 pmONT - ORD
1 stop9h 16mAlaska Airlines
Sat 10/256:00 amORD - ONT
1 stop8h 37mAlaska Airlines
Deal found 7/27$318
This Delta deal was found by Cheapflights users on 7/27. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/211:15 pmONT - ORD
1 stop6h 28mDelta
Sat 10/252:00 pmORD - ONT
1 stop10h 49mDelta
Deal found 7/27$319
This Kissandfly.com deal was found by Cheapflights users on 7/26. 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 Kissandfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/117:22 pmONT - ORD
2 stops18h 52mMultiple Airlines
Mon 8/255:20 amORD - ONT
2 stops20h 39mMultiple Airlines
Deal found 7/26$339
This Southwest deal was found by Cheapflights users on 7/28. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/305:45 amONT - ORD
2 stops9h 00mSouthwest
Tue 9/26:15 amORD - ONT
1 stop9h 05mSouthwest
Deal found 7/28$342
This Hawaiian Airlines deal was found by Cheapflights users on 7/26. 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 Hawaiian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/311:39 amONT - ORD
1 stop8h 28mHawaiian Airlines
Sat 9/66:20 amORD - ONT
1 stop9h 52mHawaiian Airlines
Deal found 7/26$356

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 July 28, 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

Wed 9/3

8:00 am-11:48 am

1 stop25h 48m

Chicago O'Hare Intl

Wed 9/10

7:20 am-7:54 pm

1 stop14h 34m

$257

OntarioChicago

ONT - ORD

ONTORD

Ontario

Tue 8/26

6:17 am-6:17 pm

1 stop10h 00m

Chicago O'Hare Intl

Sat 8/30

8:00 am-4:24 pm

1 stop10h 24m

$274

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 9/3

7:00 am-1:03 pm

Nonstop4h 03m

Chicago O'Hare Intl

Sat 9/13

7:59 pm-10:30 pm

Nonstop4h 31m

$317

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 10/15

5:45 pm-5:01 am

1 stop9h 16m

Chicago O'Hare Intl

Sat 10/25

6:00 am-12:37 pm

1 stop8h 37m

$318

OntarioChicago

ONT - ORD

ONTORD

Ontario

Tue 10/21

1:15 pm-9:43 pm

1 stop6h 28m

Chicago O'Hare Intl

Wed 10/29

2:20 pm-10:49 pm

1 stop10h 29m

$319

OntarioChicago

ONT - ORD

ONTORD

Ontario

Fri 9/26

4:08 pm-11:59 pm

1 stop5h 51m

Chicago O'Hare Intl

Sat 9/27

3:35 pm-6:06 pm

Nonstop4h 31m

$338

OntarioChicago

ONT - ORD

ONTORD

Ontario

Sat 8/30

5:45 am-4:45 pm

2 stops9h 00m

Chicago O'Hare Intl

Tue 9/2

6:15 am-1:20 pm

1 stop9h 05m

$342

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 9/3

11:39 am-10:07 pm

1 stop8h 28m

Chicago O'Hare Intl

Sat 9/6

6:20 am-2:12 pm

1 stop9h 52m

$356

OntarioChicago

ONT - ORD

ONTORD

Ontario

Tue 10/21

12:59 am-11:53 pm

1 stop20h 54m

$77

OntarioChicago

ONT - ORD

ONTORD

Ontario

Wed 8/13

7:00 am-4:50 am

1 stop19h 50m

$101

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/26

Showing 1-10 of 14 results
1
2

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 July 25, 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 80 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 July 28, 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 35% on the flight price compared to flying in the morning, 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 July 27, 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.

How much does it cost to fly round-trip from Ontario to Chicago O'Hare Intl Airport?

What’s the top layover airport for flights from Ontario to Chicago O'Hare Intl Airport?

Share of 1-stop round-trip flights from Ontario to Chicago O'Hare Intl Airport chosen by Cheapflights users in the past 12 months, using the same layover each way.

Denver (DEN) – chosen by Cheapflights users on 50% of 1-stop itineraries from Ontario to Chicago O'Hare Intl Airport on Cheapflights.

What’s the cheapest layover airport for flights from Ontario to Chicago O'Hare Intl Airport?

Average round-trip fare for 1-stop flights from Ontario to Chicago O'Hare Intl Airport, chosen by Cheapflights users in the past 12 months, with the same layover each way.

Denver (DEN) is the most affordable 1-stop option, with an average round-trip price of $151.

What’s the fastest layover option from Ontario to Chicago O'Hare Intl Airport?

Shortest average travel time for 1-stop one-way flights from Ontario to Chicago O'Hare Intl Airport, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.

Flights via Seattle (SEA) have the shortest average one-way travel time for 1-stop routes: 4h 57m.

Which airport typically offers the quickest layover for flights from Ontario to Chicago O'Hare Intl Airport?

Average layover duration for 1-stop one-way flights from Ontario to Chicago O'Hare Intl Airport, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

Flights via Seattle (SEA) offer the fastest connection on this route, with an average layover time of 0h 54m.

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 July 28, 2025.
Peruse reviews from past customers who have flown with Alaska Airlines, Southwest, and Delta 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.
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.1

Comfort

7.8

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.1

Comfort

7.8

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Southwest
8.0
Very good
4,237 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.1

Comfort

7.8

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Delta
8.0
Very good
7,971 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.1

Comfort

7.8

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Hawaiian Airlines
7.8
Good
2,604 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.1

Comfort

7.8

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
United Airlines
7.4
Good
8,893 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Boarding

8.1

Comfort

7.8

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

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.

  • 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 $259 on this airline. Additional options worth looking into are American Airlines and United Airlines, starting at $274 and $317 round-trip. Frontier is currently priced 28% 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 $77 on Frontier. Other airlines that offer cheap prices include Alaska Airlines from $144 and American Airlines from $146 one-way.

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

    On average you can expect to pay $920 for a flight from Ontario to Chicago O'Hare Intl Airport. The cheapest flight overall is $102 while the most popular route, (Ontario - Chicago O'Hare Intl) is currently priced at $240.

  • 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
Beloit
Hoffman Estates
Skokie
Naperville
Arlington Heights
Des Plaines
Elgin
Orland Park
Elk Grove Village
Racine
Rockford
Tinley Park
Merrillville
Evanston
Lake Geneva
Gurnee
Joliet
Waukegan

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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 July 28, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$99Average$172FlexibilityNo cancel feeOn-time65%
FrontierCheapest$108Average$158FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$227Average$371FlexibilityNo cancel feeOn-time69%
DeltaCheapest$241Average$339FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$246Average$481FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$246Average$473FlexibilityNo cancel feeOn-time63%

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