HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Seattle

$173+ Cheap flights from Region of Waterloo Intl (YKF) to Seattle (SEA)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/23. Fares are subject to change and may not be available on all flights or dates of travel.
YKF — SEA
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Region of Waterloo Intl to Seattle with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheap flight deals from Region of Waterloo Intl to Seattle

Discover tips and strategies to find the most affordable flight options for your journey from Region of Waterloo Intl (YKF) to Seattle (SEA). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated September 11, 2025.

Round-trip from

$234
(oojo)

One-way from

$173
(Kiwi.com)

Popular in

November

Cheapest in

May

Average price

$190
From Toronto Region of Waterloo Intl to Seattle/Tacoma Intl
Search Deals
One-way flight from Toronto Region of Waterloo Intl to Seattle/Tacoma Intl
Search Deals
Highest demand for flights based on searches. 34% potential increase in price ($163 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 21% potential price decrease ($55 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in September 2025
Search Deals

Find flight deals from Region of Waterloo Intl to Seattle

Cheapest flights from Region of Waterloo Intl to Seattle
Explore the most affordable flight options available from Region of Waterloo Intl to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 11, 2025.

This oojo deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/66:00 amYKF - SEA
1 stop17h 29mWestJet
Wed 10/221:50 pmSEA - YKF
1 stop7h 55mWestJet
Deal found 9/10$234
This oojo deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/256:00 amYKF - SEA
1 stop9h 59mWestJet
Sun 11/23:10 pmSEA - YKF
1 stop11h 18mWestJet
Deal found 9/10$240
This FlightHub deal was found by Cheapflights users on 9/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/36:20 amYKF - SEA
1 stop11h 00mWestJet
Wed 11/123:10 pmSEA - YKF
1 stop11h 18mWestJet
Deal found 9/8$271
This Trip.com deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/116:20 amYKF - SEA
1 stop11h 00mWestJet
Sun 11/163:10 pmSEA - YKF
1 stop11h 18mWestJet
Deal found 9/10$275
This Mytrip deal was found by Cheapflights users on 9/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/126:15 amYKF - SEA
1 stop9h 20mMultiple Airlines
Sat 10/188:40 amSEA - YKF
2 stops17h 50mMultiple Airlines
Deal found 9/9$279
This oojo deal was found by Cheapflights users on 9/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/176:00 amYKF - SEA
1 stop9h 59mWestJet
Mon 10/202:05 pmSEA - YKF
1 stop7h 40mWestJet
Deal found 9/9$281
This Mytrip deal was found by Cheapflights users on 9/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/266:15 amYKF - SEA
1 stop9h 20mMultiple Airlines
Sun 9/288:40 amSEA - YKF
1 stop17h 35mMultiple Airlines
Deal found 9/8$305
This FlightHub deal was found by Cheapflights users on 9/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/166:00 amYKF - SEA
1 stop9h 59mWestJet
Thu 10/231:50 pmSEA - YKF
1 stop7h 55mWestJet
Deal found 9/9$312

Cheapflights Fare Finder

 
Customize your flight search to find flights from Region of Waterloo Intl to Seattle that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated September 11, 2025.
Use the filters below to find and compare flights from Toronto Region of Waterloo Intl Airport to Seattle that are best for you.

Fly from

Region of Waterloo Intl

Fly to

Seattle

Route

Depart

Return

Price

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Mon 10/6

6:00 am-8:29 pm

1 stop17h 29m

Seattle/Tacoma Intl

Wed 10/22

1:50 pm-12:45 am

1 stop7h 55m

$234

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Mon 11/3

6:20 am-2:20 pm

1 stop11h 00m

Seattle/Tacoma Intl

Wed 11/12

3:10 pm-5:28 am

1 stop11h 18m

$271

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Sun 10/12

6:15 am-12:35 pm

1 stop9h 20m

Seattle/Tacoma Intl

Sat 10/18

8:40 am-5:30 am

2 stops17h 50m

$279

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Fri 10/17

6:00 am-12:59 pm

1 stop9h 59m

Seattle/Tacoma Intl

Mon 10/20

2:05 pm-12:45 am

1 stop7h 40m

$281

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Fri 9/26

6:15 am-12:35 pm

1 stop9h 20m

Seattle/Tacoma Intl

Sun 9/28

8:40 am-5:15 am

1 stop17h 35m

$305

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Thu 10/16

6:00 am-12:59 pm

1 stop9h 59m

Seattle/Tacoma Intl

Thu 10/23

1:50 pm-12:45 am

1 stop7h 55m

$312

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Thu 10/16

6:00 am-12:59 pm

1 stop9h 59m

Seattle/Tacoma Intl

Wed 10/22

1:50 pm-12:45 am

1 stop7h 55m

$312

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Sat 10/25

6:00 am-12:59 pm

1 stop9h 59m

Seattle/Tacoma Intl

Sun 11/2

11:55 am-5:28 am

2 stops14h 33m

$343

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Fri 10/17

6:00 am-12:59 pm

1 stop9h 59m

Seattle/Tacoma Intl

Sun 10/19

8:40 am-12:45 am

1 stop13h 05m

$367

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Mon 10/6

6:00 am-8:29 pm

1 stop17h 29m

Seattle/Tacoma Intl

Thu 10/16

1:50 pm-12:45 am

1 stop7h 55m

$375

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/9

Showing 1-10 of 20 results
1
2

Best time to book a flight from Region of Waterloo Intl to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Region of Waterloo Intl with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Toronto Region of Waterloo Intl Airport to Seattle

What is the cheapest time of day to fly from YKF to SEA?

Find hourly flight availability from Region of Waterloo Intl to Seattle. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 11, 2025.

One of the essential ways to save on airfare from Toronto Region of Waterloo Intl Airport to Seattle is to remain as flexible as possible. Flights that are at noon tend to be the most expensive. A flight in the morning could potentially save you up to 59% on airfare.

Related info for your journey

Find useful and relevant information for your journey from Region of Waterloo Intl to Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly into for flights to Seattle from Toronto Region of Waterloo Intl?

    For a flight from Toronto Region of Waterloo Intl to Seattle, you will be flying into Seattle/Tacoma Intl. Seattle/Tacoma Intl (SEA) is just 11.4 mi from the center of the city. Seattle/Tacoma Intl is the only Seattle airport and it handles 0 inbound flights from Toronto Region of Waterloo Intl per day. 0 airlines have flights to Seattle/Tacoma Intl from Toronto Region of Waterloo Intl on a regular basis.

  • How long is the flight from Toronto Region of Waterloo Intl Airport to Seattle?

    For as low as $234, WestJet can have you in Seattle from Toronto Region of Waterloo Intl Airport in 17h 29m. There are 2024 mi between Toronto Region of Waterloo Intl Airport and Seattle.

  • Can I find deals for flights from Region of Waterloo Intl to Seattle that include hotel bookings?

    Yes. In addition to deals on Region of Waterloo Intl to Seattle flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Region of Waterloo Intl to Seattle?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Region of Waterloo Intl to Seattle.

  • Can I find deals for business class flights from Region of Waterloo Intl to Seattle?

    Yes. Cheapflights offers flight deals from Region of Waterloo Intl to Seattle by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

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

    Currently, January is the cheapest month in which you can book a flight from Toronto Region of Waterloo Intl Airport to Seattle (average of $238). Flying from Toronto Region of Waterloo Intl Airport to Seattle in June is currently the most expensive (average of $388). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
SeaTac
Tukwila
Tacoma
Lakewood
Ocean Shores
Lynnwood
Edmonds
Leavenworth
Lacey
Renton
Olympia
Kent
Federal Way
Cle Elum
Puyallup
Chehalis
Kirkland
Issaquah
Aberdeen
Shoreline

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Region of Waterloo Intl to Seattle

See prices for flight routes from nearby airports that may be better suited for you.
Pearson Intl to Seattle flights
Pearson Intl to Portland flights
Toronto Island to Portland flights
Pearson Intl to Spokane flights
Hamilton to Portland flights

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.