Find Cheap Flights from Ontario to Seattle

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: Tue Sep 5 2017 Return: Tue Sep 26 2017 Trip spans 22 days
United
United
ONT
12:00a
SEA
4:45a
4h 45m
1 stop
SEA
12:00a
ONT
4:46a
4h 46m
1 stop
Depart: Tue Feb 27 2018 Return: Thu Mar 1 2018 Trip spans 3 days
Multiple Airlines
Multiple Airlines
ONT
12:00a
SEA
6:23a
6h 23m
1 stop
SEA
12:00a
ONT
4:17a
4h 17m
1 stop
Depart: Thu Oct 26 2017 Return: Mon Oct 30 2017 Trip spans 5 days
Delta
Delta
ONT
12:00a
SEA
5:08a
5h 08m
1 stop
SEA
12:00a
ONT
6:00a
6h 00m
1 stop
Depart: Fri Sep 8 2017 Return: Thu Sep 14 2017 Trip spans 7 days
Alaska Airlines
Alaska Airlines
ONT
12:00a
SEA
2:33a
2h 33m
nonstop
SEA
12:00a
ONT
2:31a
2h 31m
nonstop
Depart: Sat Sep 16 2017 Return: Wed Sep 20 2017 Trip spans 5 days
American Airlines
American Airlines
ONT
12:00a
SEA
7:24a
7h 24m
1 stop
SEA
12:00a
ONT
6:43a
6h 43m
1 stop
Depart: Wed Sep 6 2017 Return: Tue Sep 12 2017 Trip spans 7 days
United
United
ONT
12:00a
SEA
6:05a
6h 05m
1 stop
SEA
12:00a
ONT
4:46a
4h 46m
1 stop
Depart: Thu Sep 7 2017 Return: Tue Sep 12 2017 Trip spans 6 days
United
United
ONT
12:00a
SEA
4:12a
4h 12m
1 stop
SEA
12:00a
ONT
4:24a
4h 24m
1 stop
Depart: Wed Feb 28 2018 Return: Thu Mar 1 2018 Trip spans 2 days
Multiple Airlines
Multiple Airlines
ONT
12:00a
SEA
6:23a
6h 23m
1 stop
SEA
12:00a
ONT
4:08a
4h 08m
1 stop
Depart: Fri Sep 8 2017 Return: Tue Sep 12 2017 Trip spans 5 days
United
United
ONT
12:00a
SEA
5:22a
5h 22m
1 stop
SEA
12:00a
ONT
4:46a
4h 46m
1 stop
Depart: Tue Sep 12 2017 Return: Wed Sep 13 2017 Trip spans 2 days
United
United
ONT
12:00a
SEA
4:12a
4h 12m
1 stop
SEA
12:00a
ONT
7:26a
7h 26m
1 stop
Depart: Thu Sep 7 2017 Return: Thu Sep 14 2017 Trip spans 8 days
Multiple Airlines
Multiple Airlines
ONT
12:00a
SEA
5:22a
5h 22m
1 stop
SEA
12:00a
ONT
2:31a
2h 31m
nonstop
Depart: Fri Oct 27 2017 Return: Mon Oct 30 2017 Trip spans 4 days
Delta
Delta
ONT
12:00a
SEA
5:08a
5h 08m
1 stop
SEA
12:00a
ONT
4:26a
4h 26m
1 stop
Depart: Mon Sep 18 2017 Return: Wed Sep 20 2017 Trip spans 3 days
United
United
ONT
12:00a
SEA
4:12a
4h 12m
1 stop
SEA
12:00a
ONT
4:24a
4h 24m
1 stop
Depart: Sun Sep 10 2017 Return: Wed Sep 13 2017 Trip spans 4 days
Alaska Airlines
Alaska Airlines
ONT
12:00a
SEA
2:33a
2h 33m
nonstop
SEA
12:00a
ONT
2:31a
2h 31m
nonstop
Depart: Thu Sep 14 2017 Return: Tue Sep 19 2017 Trip spans 6 days
Multiple Airlines
Multiple Airlines
ONT
12:00a
SEA
2:33a
2h 33m
nonstop
SEA
12:00a
ONT
4:46a
4h 46m
1 stop
Depart: Sat Oct 28 2017 Return: Wed Nov 1 2017 Trip spans 5 days
Delta
Delta
ONT
12:00a
SEA
5:17a
5h 17m
1 stop
SEA
12:00a
ONT
4:26a
4h 26m
1 stop
Depart: Tue Sep 19 2017 Return: Tue Sep 26 2017 Trip spans 8 days
United
United
ONT
12:00a
SEA
4:12a
4h 12m
1 stop
SEA
12:00a
ONT
5:36a
5h 36m
1 stop
Depart: Thu Sep 7 2017 Return: Mon Sep 18 2017 Trip spans 12 days
Alaska Airlines
Alaska Airlines
ONT
12:00a
SEA
2:33a
2h 33m
nonstop
SEA
12:00a
ONT
2:31a
2h 31m
nonstop
Depart: Sat Sep 23 2017 Return: Fri Oct 6 2017 Trip spans 14 days
Multiple Airlines
Multiple Airlines
ONT
12:00a
SEA
7:24a
7h 24m
1 stop
SEA
12:00a
ONT
4:26a
4h 26m
1 stop
Depart: Thu Nov 9 2017 Return: Mon Nov 13 2017 Trip spans 5 days
Delta
Delta
ONT
12:00a
SEA
4:45a
4h 45m
1 stop
SEA
12:00a
ONT
4:19a
4h 19m
1 stop
* Prices are per person and are for e–tickets and include all taxes & fees in USD.

We attempt to get accurate prices, however, prices are not guaranteed.

Here's why:

We’re not the seller.
At KAYAK we don’t set the prices, so it’s not possible for us to guarantee what other companies are selling.

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Our service lets you quickly and easily compare results from hundreds of travel sites at once. In this sense, KAYAK is a search engine and we can't guarantee prices we find.

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.

If you have more questions or if you have a bad price to report to us,
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Airports
Origin

Ontario
$144
Destination

Seattle
$144
Airlines Airline reviews

69 travelers who booked a flight from Ontario to Seattle rated their chosen airlines with an average of 8.4.

Overall
8.6
Boarding
9.0
Crew
9.0
Comfort
8.3
Food
7.6
Entertainment
7.0