YKF - SEA

C$ 152 Find Cheap Flights from Toronto Region of Waterloo Intl to Seattle

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Region of Waterloo Intl to Seattle departing on 7/10. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy

KAYAK searches hundreds of travel sites at once for deals on flights to Seattle

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Toronto to Seattle, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Toronto to Seattle, as well as popular online travel agencies
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Flights Deals

Cheap Flights from Region of Waterloo Intl to Seattle (YKF-SEA)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Region of Waterloo Intl to Seattle that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Region of Waterloo Intl to Seattle

Wed, 20 Aug - Thu, 23 Oct
WestJet Logo
6:00 a.m. - 12:58 p.m.YKF-SEA
9h 58m1 stop
WestJet Logo
7:05 a.m. - 6:55 p.m.SEA-YKF
8h 50m1 stop
C$ 268WestJet
Find Deal
Wed, 27 Aug - Wed, 3 Sep
WestJet Logo
6:00 a.m. - 12:58 p.m.YKF-SEA
9h 58m1 stop
WestJet Logo
1:50 p.m. - 12:45 a.m.SEA-YKF
7h 55m1 stop
C$ 269WestJet
Find Deal
Fri, 29 Aug - Wed, 29 Oct
WestJet Logo
6:00 a.m. - 12:58 p.m.YKF-SEA
9h 58m1 stop
WestJet Logo
3:20 p.m. - 1:16 a.m.SEA-YKF
6h 56m1 stop
C$ 271WestJet
Find Deal
Wed, 17 Sep - Tue, 23 Sep
WestJet Logo
6:00 a.m. - 12:59 p.m.YKF-SEA
9h 59m1 stop
WestJet Logo
7:05 a.m. - 6:55 p.m.SEA-YKF
8h 50m1 stop
C$ 273WestJet
Find Deal
Sun, 20 Jul - Wed, 6 Aug
WestJet Logo
6:00 a.m. - 12:58 p.m.YKF-SEA
9h 58m1 stop
WestJet Logo
1:50 p.m. - 12:46 a.m.SEA-YKF
7h 56m1 stop
C$ 275WestJet
Find Deal
Wed, 6 Aug - Mon, 11 Aug
WestJet Logo
6:00 a.m. - 12:58 p.m.YKF-SEA
9h 58m1 stop
WestJet Logo
2:05 p.m. - 12:46 a.m.SEA-YKF
7h 41m1 stop
C$ 286WestJet
Find Deal
Tue, 26 Aug - Sat, 25 Oct
WestJet Logo
6:00 a.m. - 12:58 p.m.YKF-SEA
9h 58m1 stop
WestJet Logo
1:50 p.m. - 12:45 a.m.SEA-YKF
7h 55m1 stop
C$ 291WestJet
Find Deal
Wed, 20 Aug - Wed, 17 Sep
WestJet Logo
6:00 a.m. - 12:58 p.m.YKF-SEA
9h 58m1 stop
WestJet Logo
1:50 p.m. - 12:45 a.m.SEA-YKF
7h 55m1 stop
C$ 294WestJet
Find Deal
Sun, 19 Oct - Thu, 23 Oct
 Logo
6:00 a.m. - 2:09 p.m.YKF-SEA
11h 09m2 stops
 Logo
1:50 p.m. - 12:45 a.m.SEA-YKF
7h 55m1 stop
C$ 405
Find Deal
Sat, 30 Aug - Mon, 1 Sep
 Logo
6:15 a.m. - 12:58 p.m.YKF-SEA
33h 43m2 stops
 Logo
3:39 p.m. - 5:30 a.m.SEA-YKF
10h 51m2 stops
C$ 524
Find Deal
Useful Info

Good to know

Low seasonMay
High seasonJuly
Cheapest flightC$ 152
Best time to beat the crowds (59% less expensive on average)
Most popular time to fly and prices are also 22% lower on average.
Flight from Toronto Region of Waterloo Intl to Seattle

When to book flights from Region of Waterloo Intl to Seattle

Are your dates flexible? Find out the best times to travel from Region of Waterloo Intl to Seattle based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking Toronto Region of Waterloo Intl to Seattle flights

  • What is the cheapest flight from Toronto Region of Waterloo Intl Airport to Seattle?

    In the last 3 days, the lowest price for a flight from Toronto Region of Waterloo Intl Airport to Seattle was C$ 111 for a one-way ticket and C$ 196 for a round-trip.

  • Which aircraft models fly most regularly from Toronto Region of Waterloo Intl to Seattle?

    We unfortunately don’t have that data for this specific route.

  • How does KAYAK find such low prices on flights from Toronto Region of Waterloo Intl to Seattle?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Toronto Region of Waterloo Intl to Seattle.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Toronto Region of Waterloo Intl to Seattle?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Seattle from Toronto Region of Waterloo Intl is likely to change within 7 days, so travellers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Toronto Region of Waterloo Intl to Seattle?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Seattle with an airline and back to Toronto Region of Waterloo Intl with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Toronto Region of Waterloo Intl to Seattle?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Seattle from Toronto Region of Waterloo Intl up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Top airlines flying from Region of Waterloo Intl to Seattle

 
See real verified KAYAK customer reviews for airlines flying from Toronto to Seattle. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Region of Waterloo Intl to Seattle? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.2
WestJetOverall score based on 2868 reviews
6.1Entertainment
7.4Boarding
7.1Comfort
6.2Food
7.9Crew
Airline reviews

Not the greatest experience everything was pretty mediocre. My seat was by the washroom in the aisle and was not located well as everyone past each other people were right in my seat and space.

2.0 MediocreAnonymous, Jun 2025YYZ - YVR
Read more WestJet reviews

Not the greatest experience everything was pretty mediocre. My seat was by the washroom in the aisle and was not located well as everyone past each other people were right in my seat and space.

The small prop plane was crowded and the overhead luggage storage is a smaller than on the jets. Other than that, the crew was good, the flight was on time and the landing was smooth.

There was a medical emergency that the crew handled very well. There was no “entertainment” of any sort-no movie/music/whatever. Food was typical of airlines: mediocre.

Late departure, so I missed connection in Detroit. But Delta gave me a great hotel & breakfast. Just sorry I could not get anything from my checked baggage.

Crew was friendly. Lost our luggage and told us it’d be in later in the evening of the day we returned. It was not. Still after 5 days have not received it.

Internet on both flights was sketchy. Thus in flight entertainment was non- existent on MN - Balrimote leg.

We never had an experience they canceled the flight and they did not offer us an alternative flight. I had to book one on my own expense. They offered us food voucher and we could not use them at the airport it kept saying not attached to an existing flight. The people at the counter were rude and cold and they did not care about our situation

It took 30 minutes to check in with the Westjet rep. They didn’t have enough seats and she needed to make a call… I am always “randomly” selected to be checked at security. Their “randomly “ selection system may need some updating. They treat people like criminals. It is not appropriate behavior.

Found the seats very crowded—too close together ! And waited a long time for our luggage All staff at both ends were excellent!!!

Flight cancelled and Kayak switched our return flight to a red eye. Ridiculous.

Somebody either kayak or Air Canada booked my flight under my preferred name Betty instead of my legal name and I almost was denied boarding my flight

The ground staff was so rude in Toronto airport ...very rude and did not answer simple questions, and made me look like a fool. Very rude ground staff.

My flight got delayed 5 times and then got cancelled eventually, I had to get a hotel and uber and pay for food for an extra night without any plans. It was a horrible experience, instead of Air Canada, I was flying with United .

I had a nice flight with free wifi. So I was able to message family members and stream music during my flight, which made the trip go by fast. I also enjoyed flying on there Airbus A220. The plane looked very new and it also got up to speed fast down the runway and didn't need much runway to get airborne.

Overall good experience. The flight from Toronto to Denver does not have entertainment - movies to watch.

Boarding was challenging as we had to use the stairs from the tarmac. Stairs are okay but a roller bag makes it challenging.

Ensure prepaid food arrangements are appropriately understood by flight crew of who purchased and who did not

All was fine. Weather was a bit stormy, but nothing kayak can do about that! 😊

I paid for a comfort class seat and was seated in economy.

My plane was cancelled and had to be rebook for the evening was not happy.

Everything you need to know for your flight from Region of Waterloo Intl to Seattle

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