Find Cheap Flights from Seattle to Ontario

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 Seattle to Ontario

(Round-trip)
Depart: Tue Sep 12 2017 Return: Tue Sep 19 2017 Trip spans 8 days
United
United
SEA
12:00a
ONT
4:46a
4h 46m
1 stop
ONT
12:00a
SEA
4:12a
4h 12m
1 stop
Depart: Sat Sep 9 2017 Return: Sat Sep 23 2017 Trip spans 15 days
American Airlines
American Airlines
SEA
12:00a
ONT
6:43a
6h 43m
1 stop
ONT
12:00a
SEA
7:24a
7h 24m
1 stop
Depart: Wed Oct 4 2017 Return: Tue Oct 10 2017 Trip spans 7 days
Multiple Airlines
Multiple Airlines
SEA
12:00a
ONT
4:44a
4h 44m
1 stop
ONT
12:00a
SEA
5:08a
5h 08m
1 stop
Depart: Mon Oct 30 2017 Return: Wed Nov 1 2017 Trip spans 3 days
Delta
Delta
SEA
12:00a
ONT
4:26a
4h 26m
1 stop
ONT
12:00a
SEA
6:16a
6h 16m
1 stop
Depart: Wed Sep 6 2017 Return: Sat Sep 16 2017 Trip spans 11 days
Alaska Airlines
Alaska Airlines
SEA
12:00a
ONT
2:32a
2h 32m
nonstop
ONT
12:00a
SEA
2:33a
2h 33m
nonstop
Depart: Tue Sep 19 2017 Return: Tue Sep 26 2017 Trip spans 8 days
United
United
SEA
12:00a
ONT
5:36a
5h 36m
1 stop
ONT
12:00a
SEA
4:12a
4h 12m
1 stop
Depart: Sat Oct 28 2017 Return: Wed Nov 1 2017 Trip spans 5 days
United
United
SEA
12:00a
ONT
5:11a
5h 11m
1 stop
ONT
12:00a
SEA
4:28a
4h 28m
1 stop
Depart: Tue Oct 10 2017 Return: Wed Oct 11 2017 Trip spans 2 days
Multiple Airlines
Multiple Airlines
SEA
12:00a
ONT
4:24a
4h 24m
1 stop
ONT
12:00a
SEA
6:34a
6h 34m
1 stop
Depart: Wed Nov 1 2017 Return: Wed Nov 15 2017 Trip spans 15 days
United
United
SEA
12:00a
ONT
6:52a
6h 52m
1 stop
ONT
12:00a
SEA
4:28a
4h 28m
1 stop
Depart: Wed Sep 13 2017 Return: Tue Sep 26 2017 Trip spans 14 days
American Airlines
American Airlines
SEA
12:00a
ONT
6:43a
6h 43m
1 stop
ONT
12:00a
SEA
7:24a
7h 24m
1 stop
Depart: Wed Jan 3 2018 Return: Tue Jan 9 2018 Trip spans 7 days
Multiple Airlines
Multiple Airlines
SEA
12:00a
ONT
4:16a
4h 16m
1 stop
ONT
12:00a
SEA
4:51a
4h 51m
1 stop
Depart: Sat Nov 4 2017 Return: Wed Nov 15 2017 Trip spans 12 days
United
United
SEA
12:00a
ONT
6:58a
6h 58m
1 stop
ONT
12:00a
SEA
4:28a
4h 28m
1 stop
Depart: Fri Nov 3 2017 Return: Thu Nov 9 2017 Trip spans 7 days
Delta
Delta
SEA
12:00a
ONT
4:26a
4h 26m
1 stop
ONT
12:00a
SEA
4:45a
4h 45m
1 stop
Depart: Sat Sep 16 2017 Return: Sat Sep 30 2017 Trip spans 15 days
American Airlines
American Airlines
SEA
12:00a
ONT
6:43a
6h 43m
1 stop
ONT
12:00a
SEA
7:24a
7h 24m
1 stop
Depart: Fri Jan 5 2018 Return: Tue Jan 9 2018 Trip spans 5 days
Multiple Airlines
Multiple Airlines
SEA
12:00a
ONT
5:56a
5h 56m
1 stop
ONT
12:00a
SEA
4:51a
4h 51m
1 stop
Depart: Sat Nov 4 2017 Return: Fri Nov 10 2017 Trip spans 7 days
Delta
Delta
SEA
12:00a
ONT
7:43a
7h 43m
1 stop
ONT
12:00a
SEA
4:45a
4h 45m
1 stop
Depart: Tue Sep 19 2017 Return: Tue Oct 3 2017 Trip spans 15 days
American Airlines
American Airlines
SEA
12:00a
ONT
6:43a
6h 43m
1 stop
ONT
12:00a
SEA
7:24a
7h 24m
1 stop
Depart: Tue Feb 13 2018 Return: Wed Feb 14 2018 Trip spans 2 days
Multiple Airlines
Multiple Airlines
SEA
12:00a
ONT
4:16a
4h 16m
1 stop
ONT
12:00a
SEA
4:51a
4h 51m
1 stop
Depart: Wed Nov 29 2017 Return: Fri Dec 1 2017 Trip spans 3 days
Delta
Delta
SEA
12:00a
ONT
4:29a
4h 29m
1 stop
ONT
12:00a
SEA
5:55a
5h 55m
1 stop
Depart: Wed Sep 20 2017 Return: Wed Oct 4 2017 Trip spans 15 days
American Airlines
American Airlines
SEA
12:00a
ONT
6:43a
6h 43m
1 stop
ONT
12:00a
SEA
7:24a
7h 24m
1 stop
* 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

Seattle
$144
Destination

Ontario
$144
Airlines Airline reviews

75 travelers who booked a flight from Seattle to Ontario rated their chosen airlines with an average of 8.6.

Overall
8.9
Boarding
8.7
Crew
8.9
Comfort
8.6
Food
8.1
Entertainment
7.6