Find Cheap Flights from Ontario to Seattle (ONT - 03A)

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 Ontario to Seattle

(Round-trip)
Depart: Sat Dec 2 2017 Return: Tue Dec 5 2017 Trip spans 4 days
Alaska Airlines
Alaska Airlines
ONT
12:00a
SEA
2:46a
2h 46m
nonstop
SEA
12:00a
ONT
2:33a
2h 33m
nonstop
Depart: Tue Jan 9 2018 Return: Tue Jan 16 2018 Trip spans 8 days
Frontier
Frontier
ONT
12:00a
SEA
2:45p
14h 45m
1 stop
SEA
12:00a
ONT
6:01p
18h 01m
1 stop
Depart: Tue Mar 6 2018 Return: Mon Mar 12 2018 Trip spans 6 days
United
United
ONT
12:00a
SEA
4:36a
4h 36m
1 stop
SEA
12:00a
ONT
6:32a
6h 32m
1 stop
Depart: Wed Jan 17 2018 Return: Mon Jan 22 2018 Trip spans 6 days
Multiple Airlines
Multiple Airlines
ONT
12:00a
SEA
6:20a
6h 20m
1 stop
SEA
12:00a
ONT
7:02a
7h 02m
1 stop
Depart: Thu Nov 30 2017 Return: Mon Dec 4 2017 Trip spans 5 days
Delta
Delta
ONT
12:00a
SEA
6:40a
6h 40m
1 stop
SEA
12:00a
ONT
5:13a
5h 13m
1 stop
Depart: Thu Nov 30 2017 Return: Sat Dec 2 2017 Trip spans 3 days
American Airlines
American Airlines
ONT
12:00a
SEA
2:46a
2h 46m
nonstop
SEA
12:00a
ONT
6:45a
6h 45m
1 stop
Depart: Fri Dec 8 2017 Return: Sun Dec 10 2017 Trip spans 3 days
Multiple Airlines
Multiple Airlines
ONT
12:00a
SEA
2:49a
2h 49m
nonstop
SEA
12:00a
ONT
4:42a
4h 42m
1 stop
Depart: Fri Dec 8 2017 Return: Mon Dec 11 2017 Trip spans 4 days
Alaska Airlines
Alaska Airlines
ONT
12:00a
SEA
2:49a
2h 49m
nonstop
SEA
12:00a
ONT
2:33a
2h 33m
nonstop
Depart: Sat Feb 3 2018 Return: Tue Feb 6 2018 Trip spans 4 days
Frontier
Frontier
ONT
12:00a
SEA
6:20a
6h 20m
1 stop
SEA
12:00a
ONT
6:01p
18h 01m
1 stop
Depart: Fri Feb 23 2018 Return: Wed Feb 28 2018 Trip spans 6 days
Multiple Airlines
Multiple Airlines
ONT
12:00a
SEA
6:20a
6h 20m
1 stop
SEA
12:00a
ONT
5:32a
5h 32m
1 stop
Depart: Wed Feb 28 2018 Return: Sun Mar 4 2018 Trip spans 5 days
Delta
Delta
ONT
12:00a
SEA
4:45a
4h 45m
1 stop
SEA
12:00a
ONT
4:11a
4h 11m
1 stop
Depart: Thu Apr 19 2018 Return: Mon Apr 23 2018 Trip spans 5 days
Frontier
Frontier
ONT
12:00a
SEA
1:49p
13h 49m
1 stop
SEA
12:00a
ONT
8:49p
20h 49m
1 stop
Depart: Fri Apr 27 2018 Return: Sat May 5 2018 Trip spans 9 days
Frontier
Frontier
ONT
12:00a
SEA
3:47p
15h 47m
1 stop
SEA
12:00a
ONT
2:43p
14h 43m
1 stop
Depart: Thu May 3 2018 Return: Sun May 6 2018 Trip spans 4 days
American Airlines
American Airlines
ONT
12:00a
SEA
2:40a
2h 40m
nonstop
SEA
12:00a
ONT
2:34a
2h 34m
nonstop
Depart: Thu Nov 30 2017 Return: Sun Dec 3 2017 Trip spans 4 days
Multiple Airlines
Multiple Airlines
ONT
12:00a
SEA
2:46a
2h 46m
nonstop
SEA
12:00a
ONT
2:33a
2h 33m
nonstop
Depart: Sat May 12 2018 Return: Sun May 20 2018 Trip spans 9 days
Multiple Airlines
Multiple Airlines
ONT
12:00a
SEA
2:40a
2h 40m
nonstop
SEA
12:00a
ONT
2:34a
2h 34m
nonstop
Depart: Sat Nov 18 2017 Return: Sat Nov 25 2017 Trip spans 8 days
Multiple Airlines
Multiple Airlines
ONT
12:00a
SEA
5:59a
5h 59m
1 stop
SEA
12:00a
ONT
2:35a
2h 35m
nonstop
* Prices are per person and are for e–tickets and include all taxes & fees in USD.

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Airports
Origin

Ontario
$123
Destination

Seattle
$123