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Region of Waterloo Intl

$251+ Cheap flights from Seattle (SEA) to Region of Waterloo Intl (YKF)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 3/18. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — YKF
Jan 14 — Jan 211
Wed 1/14
Wed 1/21
1 adult, Economy
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Cheap flight deals from Seattle to Region of Waterloo Intl

Cheapest flights from Seattle to Region of Waterloo Intl
Explore the most affordable flight options available from Seattle to Region of Waterloo Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 15, 2025.

This FlightHub deal was found by Cheapflights users on 12/13. 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.
Fri 12/199:32 amSEA - YKF
2 stops16h 56mWestJet
Mon 12/226:20 amYKF - SEA
2 stops17h 26mWestJet
Deal found 12/13$1,139
This Trip.com deal was found by Cheapflights users on 12/14. 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.
Mon 12/153:10 pmSEA - YKF
1 stop11h 18mWestJet
Fri 12/266:25 amYKF - SEA
1 stop10h 55mWestJet
Deal found 12/14$1,279
This oojo deal was found by Cheapflights users on 12/13. 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 12/293:10 pmSEA - YKF
1 stop11h 18mWestJet
Sat 1/37:00 pmYKF - SEA
1 stop22h 20mWestJet
Deal found 12/13$1,412
This WestJet deal was found by Cheapflights users on 12/13. 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 WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/217:45 pmSEA - YKF
2 stops30h 43mWestJet
Sat 1/37:00 pmYKF - SEA
2 stops39h 37mWestJet
Deal found 12/13$1,421
This Trip.com deal was found by Cheapflights users on 12/14. 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.
Sun 12/213:10 pmSEA - YKF
1 stop11h 18mMultiple Airlines
Tue 12/236:20 amYKF - SEA
1 stop9h 03mMultiple Airlines
Deal found 12/14$1,437
This WestJet deal was found by Cheapflights users on 12/13. 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 WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/167:55 pmSEA - YKF
2 stops30h 33mWestJet
Sat 1/37:00 pmYKF - SEA
2 stops39h 37mWestJet
Deal found 12/13$1,441
This WestJet deal was found by Cheapflights users on 12/13. 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 WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/217:45 pmSEA - YKF
2 stops30h 43mWestJet
Thu 1/16:20 amYKF - SEA
1 stop11h 00mWestJet
Deal found 12/13$1,461
This WestJet deal was found by Cheapflights users on 12/13. 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 WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/167:55 pmSEA - YKF
2 stops30h 33mWestJet
Thu 1/16:20 amYKF - SEA
1 stop11h 00mWestJet
Deal found 12/13$1,481
This WestJet deal was found by Cheapflights users on 12/13. 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 WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/151:30 pmSEA - YKF
2 stops12h 58mWestJet
Sat 1/37:00 pmYKF - SEA
2 stops39h 37mWestJet
Deal found 12/13$1,488
This WestJet deal was found by Cheapflights users on 12/13. 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 WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/173:10 pmSEA - YKF
1 stop11h 18mWestJet
Sat 1/37:00 pmYKF - SEA
2 stops39h 37mWestJet
Deal found 12/13$1,508

Find flight deals from Seattle to Region of Waterloo Intl

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Region of Waterloo Intl (YKF). 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 December 15, 2025.

Most accurate provider

Mytrip
3 stars

Most trusted provider

Mytrip
3 stars

Round-trip from

$251
(Trip.com)

Popular in

December

Cheapest in

November

Average price

$553
Provider with most accurate pricing for Seattle/Tacoma Intl-Toronto Region of Waterloo Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Toronto Region of Waterloo Intl flights.
Search Deals
From Seattle/Tacoma Intl to Toronto Region of Waterloo Intl
Search Deals
High demand for flights, 6% potential price rise
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($15 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Seattle to Region of Waterloo Intl 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 December 15, 2025.
Use the filters below to find and compare flights from Seattle to Toronto Region of Waterloo Intl Airport that are best for you.

Fly from

Seattle

Fly to

Region of Waterloo Intl

Route

Depart

Return

Price

SeattleToronto

SEA - YKF

SEAYKF

Seattle/Tacoma Intl

Wed 3/18

3:10 pm-5:29 am

1 stop11h 19m

Toronto Region of Waterloo Intl

Tue 3/24

6:20 am-2:19 pm

1 stop10h 59m

$251

SeattleToronto

SEA - YKF

SEAYKF

Seattle/Tacoma Intl

Wed 3/11

3:10 pm-5:29 am

1 stop11h 19m

Toronto Region of Waterloo Intl

Sat 3/14

7:00 pm-2:19 pm

1 stop22h 19m

$251

SeattleToronto

SEA - YKF

SEAYKF

Seattle/Tacoma Intl

Fri 1/9

3:10 pm-5:28 am

1 stop11h 18m

Toronto Region of Waterloo Intl

Mon 1/12

6:20 am-2:20 pm

1 stop11h 00m

$274

SeattleToronto

SEA - YKF

SEAYKF

Seattle/Tacoma Intl

Mon 5/4

7:05 am-12:45 am

1 stop14h 40m

Toronto Region of Waterloo Intl

Mon 5/11

6:00 am-8:28 pm

1 stop17h 28m

$275

SeattleToronto

SEA - YKF

SEAYKF

Seattle/Tacoma Intl

Wed 4/15

3:10 pm-5:29 am

1 stop11h 19m

Toronto Region of Waterloo Intl

Fri 5/8

6:00 am-8:28 pm

1 stop17h 28m

$276

SeattleToronto

SEA - YKF

SEAYKF

Seattle/Tacoma Intl

Wed 3/18

3:10 pm-5:29 am

1 stop11h 19m

Toronto Region of Waterloo Intl

Mon 3/23

6:20 am-2:19 pm

1 stop10h 59m

$277

SeattleToronto

SEA - YKF

SEAYKF

Seattle/Tacoma Intl

Wed 4/15

3:10 pm-5:29 am

1 stop11h 19m

Toronto Region of Waterloo Intl

Sat 5/9

6:00 am-1:08 pm

1 stop10h 08m

$289

SeattleToronto

SEA - YKF

SEAYKF

Seattle/Tacoma Intl

Fri 1/30

3:10 pm-5:28 am

1 stop11h 18m

Toronto Region of Waterloo Intl

Sun 2/1

7:05 am-2:19 pm

1 stop10h 14m

$327

SeattleToronto

SEA - YKF

SEAYKF

Seattle/Tacoma Intl

Fri 4/17

3:10 pm-5:29 am

1 stop11h 19m

Toronto Region of Waterloo Intl

Fri 5/8

6:00 am-8:28 pm

1 stop17h 28m

$437

SeattleToronto

SEA - YKF

SEAYKF

Seattle/Tacoma Intl

Wed 2/18

3:10 pm-5:29 am

1 stop11h 19m

Toronto Region of Waterloo Intl

Sat 2/21

7:00 pm-2:19 pm

1 stop22h 19m

$459

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/13

Showing 1-10 of 14 results
1
2

Compare providers for flights from Seattle to Region of Waterloo Intl

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to Region of Waterloo Intl in December.
ProviderPrice AccuracyTrust Score*
eDreamsPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
MytripPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Seattle-Toronto Region of Waterloo Intl Airport flights, users find the pricing of Mytrip to be most consistent on Cheapflights vs. Mytrip Users can find the same prices on Seattle-Toronto Region of Waterloo Intl Airport flight deals on Cheapflights vs. Mytrip >95% of the time. Price accuracy is based on data collected from Seattle-Toronto Region of Waterloo Intl Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Seattle-Toronto Region of Waterloo Intl Airport flights, Cheapflights users trust Mytrip the most. Mytrip has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-Toronto Region of Waterloo Intl Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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

Have a flexible travel schedule? Discover the best time to fly to Region of Waterloo Intl from Seattle 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 Seattle to Toronto Region of Waterloo Intl Airport

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

Find hourly flight availability from Seattle to Region of Waterloo Intl. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated December 15, 2025.

One of the essential ways to save on airfare from Seattle to Toronto Region of Waterloo Intl Airport is to remain as flexible as possible. Flights that are at noon tend to be the most expensive. A flight in the evening could potentially save you up to 54% on airfare.

Related info for your journey

Find useful and relevant information for your journey from Seattle to Region of Waterloo Intl. 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 from for flights from Seattle to Toronto Region of Waterloo Intl?

    Seattle/Tacoma Intl (SEA), located 11.4 mi from the city center, is the airport you fly out of when you book flights from Seattle to Toronto Region of Waterloo Intl. 0 airlines have flights from Seattle/Tacoma Intl to Toronto Region of Waterloo Intl on a regular basis. Booking flights from Seattle/Tacoma Intl to Toronto Region of Waterloo Intl should not be difficult; the airport handles an average of 0 outbound flights to Toronto Region of Waterloo Intl per day.

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

    Airlines like WestJet fly from Seattle to Toronto Region of Waterloo Intl Airport in about 11h 19m. The time it takes to get you to your destination can typically vary by up to . The distance between Seattle and Toronto Region of Waterloo Intl Airport is about 2024 mi.

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

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

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

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

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

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

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