Travelers have found it’s best to book a flight 45 days in advance to save up to 61% compared to booking the same week of travel. As your travel date approaches, the cost of this flight route may potentially increase. While opting to book 45 days out may not be an option for all, there are still additional ways to secure a deal in the near future. You might find a flight from Illinois to Ontario 1-2 weeks in advance for as low as $323, or $459 for flights within the next 24 hours.
Due to multiple factors, expect to potentially pay more when booking in March. For low rates, September can be a great choice for travel to Ontario. Flights to Ontario from Illinois in September are about $304 on average during September, but can be found for as low as $64.
Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Illinois to Ontario as you normally would.
Fly from
Fly to
Budget
$120 - $349
Route
Depart
Return
Price
Lambert-St LouisOntario
STL - ONT
STLONT
Lambert-St Louis
Mon 6/3
1 stop5h 55m
Ontario
Tue 6/4
1 stop6h 30m
Chicago O'Hare IntlOntario
ORD - ONT
ORDONT
Chicago O'Hare Intl
Tue 5/21
1 stop17h 59m
Ontario
Wed 5/22
1 stop8h 38m
Lambert-St LouisOntario
STL - ONT
STLONT
Lambert-St Louis
Mon 6/3
1 stop5h 55m
Ontario
Wed 6/5
1 stop11h 47m
Chicago MidwayOntario
MDW - ONT
MDWONT
Chicago Midway
Tue 5/21
1 stop11h 14m
Ontario
Wed 5/22
1 stop8h 05m
Lambert-St LouisOntario
STL - ONT
STLONT
Lambert-St Louis
Sat 5/18
1 stop8h 36m
Ontario
Mon 5/20
1 stop10h 10m
Chicago MidwayOntario
MDW - ONT
MDWONT
Chicago Midway
Tue 5/21
1 stop11h 14m
Ontario
Sat 5/25
1 stop5h 40m
Chicago MidwayOntario
MDW - ONT
MDWONT
Chicago Midway
Tue 5/21
1 stop13h 54m
Ontario
Thu 5/23
1 stop28h 43m
Moline Quad-CityOntario
MLI - ONT
MLIONT
Moline Quad-City
Sat 9/21
1 stop7h 22m
Ontario
Tue 9/24
1 stop7h 41m
Moline Quad-CityOntario
MLI - ONT
MLIONT
Moline Quad-City
Fri 5/24
2 stops9h 33m
Ontario
Thu 5/30
1 stop6h 21m
No data available for this route at this time. Please check back soon.
Crew
Food
Comfort
Entertainment
Boarding
Overall
Reviews
I was very relaxed and calm so I took a brief nap. The flight was pretty smooth.
Crew
Food
Comfort
Entertainment
Boarding
Overall
Reviews
I was very relaxed and calm so I took a brief nap. The flight was pretty smooth.
Crew
Food
Comfort
Entertainment
Boarding
Overall
Reviews
I was very relaxed and calm so I took a brief nap. The flight was pretty smooth.
Crew
Food
Comfort
Entertainment
Boarding
Overall
Reviews
I was very relaxed and calm so I took a brief nap. The flight was pretty smooth.
Crew
Food
Comfort
Entertainment
Boarding
Overall
Reviews
I was very relaxed and calm so I took a brief nap. The flight was pretty smooth.
Crew
Food
Comfort
Entertainment
Boarding
Overall
Reviews
I was very relaxed and calm so I took a brief nap. The flight was pretty smooth.
0%of flight departures | Early morningMidnight to 6 am |
---|---|
100%of flight departures | Morning6 am to noon |
0%of flight departures | AfternoonNoon to 6 pm |
0%of flight departures | Evening6 pm to midnight |
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