Find Deals on Flights from Lambert-St Louis to Ontario (STL - ONT)

Depart
Return
1 adult
Adults
18-64
Seniors
65+
Youths
12-17
Children
2-11
Seat Infants
under 2
Lap Infants
under 2
The price shown for each flight will be the average for all passengers including any infants.
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Book cheap flights from Lambert-St Louis to Ontario

(Round-trip)
Depart: Tue Mar 28 2017 Return: Wed Apr 5 2017 Trip spans 9 days
American Airlines
American Airlines
STL
2:00a
ONT
8:02a
6h 02m
1 stop
ONT
12:30p
STL
5:55p
5h 25m
1 stop
Depart: Tue Apr 4 2017 Return: Sat Apr 8 2017 Trip spans 5 days
Delta
Delta
STL
2:55p
ONT
8:49p
5h 54m
1 stop
ONT
9:15a
STL
2:49p
5h 34m
1 stop
Depart: Tue Apr 25 2017 Return: Tue May 2 2017 Trip spans 8 days
United
United
STL
3:30a
ONT
10:36a
7h 06m
1 stop
ONT
3:56a
STL
11:34a
7h 38m
1 stop
Depart: Fri May 19 2017 Return: Sun May 28 2017 Trip spans 10 days
Major Airline
Major Airline
STL
6:35a
ONT
2:10p
7h 35m
1 stop
ONT
4:00a
STL
1:16p
9h 16m
1 stop
Depart: Wed Mar 29 2017 Return: Wed Apr 5 2017 Trip spans 8 days
American Airlines
American Airlines
STL
2:00a
ONT
8:02a
6h 02m
1 stop
ONT
12:30p
STL
5:55p
5h 25m
1 stop
Depart: Wed Apr 5 2017 Return: Sat Apr 8 2017 Trip spans 4 days
Delta
Delta
STL
1:40a
ONT
7:47a
6h 07m
1 stop
ONT
9:15a
STL
2:49p
5h 34m
1 stop
Depart: Wed Apr 26 2017 Return: Tue May 2 2017 Trip spans 7 days
United
United
STL
3:05a
ONT
10:06a
7h 01m
1 stop
ONT
3:56a
STL
11:34a
7h 38m
1 stop
Depart: Mon Mar 27 2017 Return: Wed Apr 5 2017 Trip spans 10 days
American Airlines
American Airlines
STL
2:00p
ONT
7:39p
5h 39m
1 stop
ONT
12:30p
STL
5:55p
5h 25m
1 stop
Depart: Thu Apr 6 2017 Return: Sat Apr 8 2017 Trip spans 3 days
Delta
Delta
STL
1:40a
ONT
7:47a
6h 07m
1 stop
ONT
9:15a
STL
2:49p
5h 34m
1 stop
Depart: Thu Mar 30 2017 Return: Wed Apr 5 2017 Trip spans 7 days
American Airlines
American Airlines
STL
3:17a
ONT
9:48a
6h 31m
1 stop
ONT
12:30p
STL
5:55p
5h 25m
1 stop
Depart: Tue Mar 14 2017 Return: Tue Mar 21 2017 Trip spans 8 days
United
United
STL
3:10a
ONT
9:51a
6h 41m
1 stop
ONT
9:30a
STL
4:59p
7h 29m
1 stop
Depart: Wed Mar 22 2017 Return: Sun Mar 26 2017 Trip spans 5 days
Major Airline
Major Airline
STL
11:20a
ONT
3:52a
16h 32m
2 stops
ONT
12:45p
STL
4:04a
15h 19m
2 stops
Depart: Sat Apr 1 2017 Return: Wed Apr 5 2017 Trip spans 5 days
American Airlines
American Airlines
STL
3:17a
ONT
9:48a
6h 31m
1 stop
ONT
12:30p
STL
5:55p
5h 25m
1 stop
Depart: Thu May 4 2017 Return: Sun May 7 2017 Trip spans 4 days
Delta
Delta
STL
1:40a
ONT
7:39a
5h 59m
1 stop
ONT
12:30p
STL
6:07p
5h 37m
1 stop
Depart: Wed Mar 15 2017 Return: Tue Mar 21 2017 Trip spans 7 days
United
United
STL
3:10a
ONT
9:51a
6h 41m
1 stop
ONT
9:30a
STL
4:59p
7h 29m
1 stop
Depart: Thu Mar 23 2017 Return: Sun Mar 26 2017 Trip spans 4 days
Major Airline
Major Airline
STL
4:35p
ONT
10:27p
5h 52m
1 stop
ONT
5:45p
STL
10:45p
5h 00m
1 stop
Depart: Thu Mar 16 2017 Return: Mon Mar 20 2017 Trip spans 5 days
American Airlines
American Airlines
STL
3:17a
ONT
9:48a
6h 31m
1 stop
ONT
9:15p
STL
2:47a
5h 32m
1 stop
Depart: Mon Mar 13 2017 Return: Tue Mar 21 2017 Trip spans 9 days
United
United
STL
12:40p
ONT
6:14p
5h 34m
1 stop
ONT
9:30a
STL
4:59p
7h 29m
1 stop
Depart: Sun Mar 26 2017 Return: Wed Apr 5 2017 Trip spans 11 days
American Airlines
American Airlines
STL
4:35p
ONT
10:27p
5h 52m
1 stop
ONT
12:30p
STL
5:55p
5h 25m
1 stop
Depart: Sun Feb 26 2017 Return: Tue Mar 7 2017 Trip spans 10 days
Major Airline
Major Airline
STL
12:00a
ONT
5:05a
5h 05m
nonstop
ONT
8:00a
STL
9:05a
1h 05m
nonstop
* Prices are per person and are for e–tickets and include all taxes & fees in USD.

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Why aren’t prices accurate 100% of the time?
Prices on airline seats, hotel rooms and car rentals can change frequently. Several people may also be trying to buy the same travel option simultaneously. As a result, you may find, on occasion, that certain prices are no longer available.

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Airports
Origin

St. Louis
$308
Destination

Ontario
$308