Cheap flights from Ontario to Illinois from $104

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Ontario to Illinois departing on 8/13. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
0 bags

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Cheap round-trip flights

Frontier Logo
8:59 pm - 9:06 amONT-STL
10h 07m1 stop
Frontier Logo
7:52 pm - 11:50 pmSTL-ONT
5h 58m1 stop
$194Frontier
Find Deal
Thu, Oct 2 - Tue, Oct 7
Frontier Logo
7:30 pm - 8:52 pmONT-ORD
23h 22m1 stop
Frontier Logo
9:47 pm - 9:56 pmORD-ONT
26h 09m1 stop
$218Frontier
Find Deal
Thu, Sep 4 - Mon, Sep 8
Frontier Logo
12:59 am - 9:11 amONT-STL
6h 12m1 stop
Frontier Logo
10:39 am - 6:15 pmSTL-ONT
9h 36m1 stop
$220Frontier
Find Deal
Tue, Sep 2 - Sun, Sep 7
Frontier Logo
12:59 am - 11:41 amONT-MDW
8h 42m1 stop
Frontier Logo
6:31 pm - 11:50 pmMDW-ONT
7h 19m1 stop
$221Frontier
Find Deal
Sun, Aug 17 - Fri, Aug 22
American Airlines Logo
6:17 am - 6:17 pmONT-ORD
10h 00m1 stop
American Airlines Logo
9:55 am - 5:50 pmORD-ONT
9h 55m1 stop
$275American Airlines
Find Deal
Tue, Aug 26 - Sat, Aug 30
Delta Logo
1:15 pm - 9:57 pmONT-ORD
6h 42m1 stop
Delta Logo
7:55 am - 12:17 pmORD-ONT
6h 22m1 stop
$279Delta
Find Deal
Sat, Sep 13 - Sat, Sep 20
American Airlines Logo
6:17 am - 8:57 pmONT-ORD
12h 40m1 stop
American Airlines Logo
8:00 am - 5:52 pmORD-ONT
11h 52m1 stop
$285American Airlines
Find Deal
Sat, Aug 9 - Wed, Aug 20
Delta Logo
12:00 pm - 10:30 pmONT-MLI
8h 30m1 stop
Delta Logo
5:55 am - 11:24 amMLI-ONT
7h 29m1 stop
$289Delta
Find Deal
Tue, Oct 21 - Tue, Oct 28
United Airlines Logo
5:10 am - 4:43 pmONT-PIA
9h 33m2 stops
United Airlines Logo
5:19 pm - 10:30 pmPIA-ONT
7h 11m1 stop
$339United Airlines
Find Deal
Fri, Aug 22 - Thu, Aug 28
United Airlines Logo
7:00 am - 4:43 pmONT-PIA
7h 43m1 stop
United Airlines Logo
5:19 pm - 10:30 pmPIA-ONT
7h 11m1 stop
$347United Airlines
Find Deal
Fri, Aug 22 - Thu, Aug 28

Delta flights from Ontario to Illinois

Our best Delta deals on Ontario to Illinois flight tickets
Delta
Sep 13
ONT1:15 pmOntario
6h 42m
1 stop
ORD9:57 pmChicago O'Hare Intl
Sep 20
ORD7:55 amChicago O'Hare Intl
6h 22m
1 stop
ONT12:17 pmOntario
Delta
Oct 21
ONT12:00 pmOntario
8h 30m
1 stop
MLI10:30 pmMoline Quad-City
Oct 28
MLI5:55 amMoline Quad-City
7h 29m
1 stop
ONT11:24 amOntario
Delta
Oct 18
ONT12:00 pmOntario
8h 30m
1 stop
MLI10:30 pmMoline Quad-City
Oct 29
MLI5:55 amMoline Quad-City
7h 29m
1 stop
ONT11:24 amOntario

Frontier flights from Ontario to Illinois

Our best Frontier deals on Ontario to Illinois flight tickets
Frontier
Oct 2
ONT8:59 pmOntario
10h 07m
1 stop
STL9:06 amLambert-St Louis
Oct 7
STL7:52 pmLambert-St Louis
5h 58m
1 stop
ONT11:50 pmOntario
Frontier
Sep 4
ONT7:30 pmOntario
23h 22m
1 stop
ORD8:52 pmChicago O'Hare Intl
Sep 8
ORD9:47 pmChicago O'Hare Intl
26h 09m
1 stop
ONT9:56 pmOntario
Frontier
Sep 2
ONT12:59 amOntario
6h 12m
1 stop
STL9:11 amLambert-St Louis
Sep 7
STL10:39 amLambert-St Louis
9h 36m
1 stop
ONT6:15 pmOntario

See travel insights to Illinois from

How to get the cheapest flight ticket from Ontario to Illinois

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly to Illinois?

The cheapest month to fly to Illinois from Ontario is in November. Flight prices, which tend to average around $227, are often lower during this time because this is during the off-season. If you aren’t able to travel to Illinois during the month of November, then flying in September is also cheap. Prices for this month can be found on momondo for an average of $268.

What is the cheapest day to depart on your flight to Illinois?

The cheapest day to depart from Ontario to Illinois is on a Thursday when prices can be found for as low as $441. Flights from Ontario to Illinois on a Sunday will generally be more expensive and average around $494. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

What is the cheapest time of day to depart on your flight to Illinois?

Our most recent data shows that the best time of day to fly to Illinois is in the evening. Flights from Ontario to Illinois during this time can be as low as $246. Flights at noon are often more expensive with an average ticket price of $531.

What is the cheapest Ontario to Illinois flight route?

Fly from Ontario to Chicago O'Hare Intl for the best Ontario - Illinois flight prices

How far in advance should I book a flight to Illinois?

You are more likely to see cheaper flights to Illinois from Ontario when booking weeks ahead of your departure date. In general, you can expect to find flights to Illinois for around $363 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Illinois from Ontario for as low as $258 on momondo.

What cabin class options are available on Ontario to Illinois flights?

There are 4 cabin classes available to choose from on Ontario to Illinois flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Ontario to Illinois flights?

You could potentially save up to 41% on your flight if you consider stops on a Ontario to Illinois flight.

Cheap Ontario to Illinois flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Ontario to Illinois

Best Price Found

$104

Fastest flight time

3h 45m

Direct flights

Every day

Airports in Illinois

5 airports
The best one-way flight to Illinois from Ontario in the past 72 hours is $104. The best round-trip flight deal from Ontario to Illinois found on momondo in the last 72 hours is $194.
The fastest flight from Ontario to Illinois takes 3h 45m
Direct flights go from Ontario to Illinois every day.
There are 5 airports near Illinois: Chicago O'Hare Intl (ORD), Chicago Midway (MDW), Greater Peoria (PIA), Lambert-St Louis (STL), Moline Quad-City (MLI)

  • When did momondo last update prices for flights from Ontario Airport to Illinois?

    Prices for flights from Ontario Airport to Illinois were last updated today.

  • How many operators does momondo search for flights from Ontario Airport to Illinois?

  • How old do you have to be to fly from Ontario Airport to Illinois?

    The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Ontario Airport to Illinois.

  • What documentation or ID do you need to fly to Illinois?

    The travel and health documents required for your trip to Illinois can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Illinois. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

  • What is the most popular plane model from Ontario to Illinois?


Best airlines flying from Ontario to Illinois

Compare and see reviews for airlines that fly from Ontario to Illinois with momondo
Airline
Rating
Free Cancellation
Price
Spirit AirlinesPriceFrom $99Free CancellationRating
6.3
8,035 reviews
Search Spirit Airlines flights
FrontierPriceFrom $108Free CancellationRating
5.9
3,251 reviews
Search Frontier flights
United AirlinesPriceFrom $227Free CancellationRating
7.4
8,864 reviews
Search United Airlines flights
SouthwestPriceFrom $237Free CancellationRating
8.0
4,238 reviews
Search Southwest flights
DeltaPriceFrom $241Free CancellationRating
8.0
7,958 reviews
Search Delta flights
American AirlinesPriceFrom $246Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to Illinois?

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from Ontario to Illinois. momondo saves you time and could save you money on your trip.

Can I find flights from Ontario to Illinois with flexible booking policies on momondo?

Flights from Ontario to Illinois with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.

How can momondo help me find flights from Ontario to Illinois?

Once you have performed a search for Ontario to Illinois flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

I’m not ready to book a flight from Ontario to Illinois right now. Can momondo alert me if prices change?

If you are simply researching potential flights to Illinois, momondo offers a useful price alert feature which will track prices for flights to Illinois from Ontario and alert you when they change.


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1 adult
Tue 7/22
Tue 7/29

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