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
Students
under 26
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: Sat Jan 14 2017 Return: Wed Jan 18 2017 Trip spans 5 days
American Airlines
American Airlines
STL
1:00a
ONT
7:09a
6h 09m
1 stop
ONT
9:24a
STL
2:56p
5h 32m
1 stop
Depart: Thu Jan 19 2017 Return: Sat Jan 21 2017 Trip spans 3 days
United
United
STL
2:28a
ONT
9:47a
7h 19m
1 stop
ONT
12:38a
STL
6:09a
5h 31m
1 stop
Depart: Thu Mar 2 2017 Return: Mon Mar 6 2017 Trip spans 5 days
Major Airline
Major Airline
STL
6:10a
ONT
12:23p
30h 13m
1 stop
ONT
10:59a
STL
3:25a
16h 26m
1 stop
Depart: Fri Feb 17 2017 Return: Wed Feb 22 2017 Trip spans 6 days
Delta
Delta
STL
1:20p
ONT
7:44p
6h 24m
1 stop
ONT
5:15a
STL
10:39a
5h 24m
1 stop
Depart: Fri Mar 10 2017 Return: Tue Mar 14 2017 Trip spans 4 days
Alaska Airlines
Alaska Airlines
STL
1:30a
ONT
2:25p
12h 55m
1 stop
ONT
4:45p
STL
8:04a
15h 19m
1 stop
Depart: Wed Jan 18 2017 Return: Sat Jan 21 2017 Trip spans 4 days
American Airlines
American Airlines
STL
10:25a
ONT
5:13p
6h 48m
1 stop
ONT
1:15a
STL
6:44a
5h 29m
1 stop
Depart: Sat Jan 21 2017 Return: Mon Jan 23 2017 Trip spans 3 days
United
United
STL
4:01a
ONT
9:47a
5h 46m
1 stop
ONT
12:38a
STL
8:44a
8h 06m
1 stop
Depart: Fri Jan 13 2017 Return: Wed Jan 18 2017 Trip spans 6 days
Major Airline
Major Airline
STL
8:30p
ONT
9:24a
12h 54m
2 stops
ONT
1:00a
STL
11:56a
10h 56m
2 stops
Depart: Mon Jan 23 2017 Return: Tue Jan 31 2017 Trip spans 9 days
American Airlines
American Airlines
STL
10:25a
ONT
5:13p
6h 48m
1 stop
ONT
3:25a
STL
9:32a
6h 07m
1 stop
Depart: Tue Jan 31 2017 Return: Tue Feb 7 2017 Trip spans 8 days
United
United
STL
4:01a
ONT
9:43a
5h 42m
1 stop
ONT
12:38a
STL
5:55a
5h 17m
1 stop
Depart: Tue Jan 24 2017 Return: Sat Feb 4 2017 Trip spans 12 days
American Airlines
American Airlines
STL
7:45a
ONT
3:12p
7h 27m
1 stop
ONT
1:09a
STL
7:38a
6h 29m
1 stop
Depart: Fri Jan 27 2017 Return: Mon Jan 30 2017 Trip spans 4 days
United
United
STL
11:20a
ONT
5:15p
5h 55m
1 stop
ONT
12:38a
STL
5:55a
5h 17m
1 stop
Depart: Tue Mar 14 2017 Return: Wed Mar 22 2017 Trip spans 9 days
American Airlines
American Airlines
STL
3:09p
ONT
9:08p
5h 59m
1 stop
ONT
2:34a
STL
8:20a
5h 46m
1 stop
Depart: Sat Dec 24 2016 Return: Fri Dec 30 2016 Trip spans 7 days
American Airlines
American Airlines
STL
12:55p
ONT
6:49p
5h 54m
1 stop
ONT
8:10p
STL
3:44a
7h 34m
1 stop
Depart: Thu Mar 23 2017 Return: Tue Mar 28 2017 Trip spans 6 days
Major Airline
Major Airline
STL
10:25p
ONT
10:31a
12h 06m
1 stop
ONT
9:30a
STL
8:12a
22h 42m
1 stop
Depart: Fri Jan 6 2017 Return: Thu Jan 12 2017 Trip spans 7 days
American Airlines
American Airlines
STL
9:30a
ONT
3:19p
5h 49m
1 stop
ONT
4:55a
STL
10:14a
5h 19m
1 stop
Depart: Mon Dec 12 2016 Return: Wed Dec 21 2016 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
Depart: Tue Jun 13 2017 Return: Sat Jun 17 2017 Trip spans 5 days
Delta
Delta
STL
2:45p
ONT
8:44p
5h 59m
1 stop
ONT
2:00a
STL
7:36a
5h 36m
1 stop
Depart: Sun Feb 26 2017 Return: Sun Mar 5 2017 Trip spans 8 days
United
United
STL
3:52a
ONT
9:45a
5h 53m
1 stop
ONT
12:30a
STL
5:53a
5h 23m
1 stop
Depart: Fri Jan 20 2017 Return: Mon Jan 23 2017 Trip spans 4 days
American Airlines
American Airlines
STL
9:30a
ONT
3:28p
5h 58m
1 stop
ONT
11:30a
STL
4:51p
5h 21m
1 stop
* Prices are per person and are for e–tickets and include all taxes & fees in USD.

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Airports
Origin

St. Louis
$308
Destination

Ontario
$308