Find Cheap 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: Sat Sep 16 2017 Return: Tue Sep 19 2017 Trip spans 4 days
American Airlines
American Airlines
STL
3:17a
ONT
9:46a
6h 29m
1 stop
ONT
8:59p
STL
2:43a
5h 44m
1 stop
Depart: Thu Sep 7 2017 Return: Tue Sep 19 2017 Trip spans 13 days
United
United
STL
3:28a
ONT
10:38a
7h 10m
1 stop
ONT
8:40a
STL
4:09p
7h 29m
1 stop
Depart: Wed Oct 4 2017 Return: Wed Oct 11 2017 Trip spans 8 days
Southwest
Southwest
STL
1:40p
ONT
7:45p
6h 05m
1 stop
ONT
3:20a
STL
9:15a
5h 55m
1 stop
Depart: Sun Jun 25 2017 Return: Sun Jul 2 2017 Trip spans 8 days
Major Airline
Major Airline
STL
11:17a
ONT
4:16p
28h 59m
2 stops
ONT
11:50a
STL
7:07a
19h 17m
2 stops
Depart: Wed Jun 28 2017 Return: Sat Jul 1 2017 Trip spans 4 days
Delta
Delta
STL
1:50a
ONT
7:39a
5h 49m
1 stop
ONT
8:45a
STL
2:50p
6h 05m
1 stop
Depart: Mon Sep 18 2017 Return: Tue Sep 19 2017 Trip spans 2 days
American Airlines
American Airlines
STL
1:38p
ONT
9:08p
7h 30m
1 stop
ONT
8:59p
STL
2:43a
5h 44m
1 stop
Depart: Tue Sep 19 2017 Return: Wed Sep 20 2017 Trip spans 2 days
American Airlines
American Airlines
STL
3:09p
ONT
9:08p
5h 59m
1 stop
ONT
8:59p
STL
2:43a
5h 44m
1 stop
Depart: Mon Aug 7 2017 Return: Sat Aug 26 2017 Trip spans 20 days
United
United
STL
12:32p
ONT
6:40p
6h 08m
1 stop
ONT
1:35a
STL
9:32a
7h 57m
1 stop
Depart: Sat Aug 12 2017 Return: Tue Aug 22 2017 Trip spans 11 days
United
United
STL
3:00a
ONT
10:15a
7h 15m
1 stop
ONT
12:50p
STL
7:17p
6h 27m
1 stop
Depart: Wed Aug 9 2017 Return: Tue Aug 22 2017 Trip spans 14 days
American Airlines
American Airlines
STL
10:40a
ONT
4:26p
5h 46m
1 stop
ONT
12:30p
STL
5:51p
5h 21m
1 stop
Depart: Mon Aug 14 2017 Return: Tue Aug 22 2017 Trip spans 9 days
United
United
STL
12:32p
ONT
6:40p
6h 08m
1 stop
ONT
12:50p
STL
7:17p
6h 27m
1 stop
Depart: Fri Aug 11 2017 Return: Tue Aug 22 2017 Trip spans 12 days
American Airlines
American Airlines
STL
10:40a
ONT
4:26p
5h 46m
1 stop
ONT
12:30p
STL
5:51p
5h 21m
1 stop
Depart: Wed Nov 8 2017 Return: Wed Nov 15 2017 Trip spans 8 days
Southwest
Southwest
STL
12:15a
ONT
5:30a
5h 15m
1 stop
ONT
1:20a
STL
6:40a
5h 20m
1 stop
Depart: Sun Aug 13 2017 Return: Tue Aug 22 2017 Trip spans 10 days
American Airlines
American Airlines
STL
4:50p
ONT
9:55p
5h 05m
1 stop
ONT
12:30p
STL
5:51p
5h 21m
1 stop
Depart: Wed Aug 2 2017 Return: Sun Aug 6 2017 Trip spans 5 days
Major Airline
Major Airline
STL
10:30p
ONT
10:16a
11h 46m
1 stop
ONT
11:50a
STL
7:07a
19h 17m
1 stop
Depart: Sun Sep 17 2017 Return: Tue Sep 19 2017 Trip spans 3 days
United
United
STL
3:28a
ONT
10:38a
7h 10m
1 stop
ONT
8:40a
STL
4:09p
7h 29m
1 stop
Depart: Tue Aug 15 2017 Return: Tue Aug 22 2017 Trip spans 8 days
American Airlines
American Airlines
STL
10:40a
ONT
4:26p
5h 46m
1 stop
ONT
12:30p
STL
5:51p
5h 21m
1 stop
Depart: Wed Jun 7 2017 Return: Wed Jun 14 2017 Trip spans 8 days
Southwest
Southwest
STL
2:45p
ONT
8:20p
5h 35m
1 stop
ONT
8:45a
STL
3:00p
6h 15m
1 stop
Depart: Fri Jun 16 2017 Return: Tue Jun 20 2017 Trip spans 5 days
United
United
STL
12:25p
ONT
6:42p
6h 17m
1 stop
ONT
12:50p
STL
7:26p
6h 36m
1 stop
Depart: Fri Sep 15 2017 Return: Tue Sep 19 2017 Trip spans 5 days
American Airlines
American Airlines
STL
2:00p
ONT
7:39p
5h 39m
1 stop
ONT
12:30p
STL
5:51p
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