HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Seattle

$179+ 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 7/20. Fares are subject to change and may not be available on all flights or dates of travel.
YKF — SEA
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
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 June 12, 2025.

Round-trip from

$256
(WestJet)

One-way from

$179
(Mytrip)

Popular in

November

Cheapest in

May

Average price

$452
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. 40% potential increase in price ($229 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 18% potential price decrease ($52 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 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 June 12, 2025.

This WestJet deal was found by Cheapflights users on 6/10. 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 WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/287:45 pmYKF - SEA
2 stops19h 46mWestJet
Fri 9/51:50 pmSEA - YKF
1 stop7h 55mWestJet
Deal found 6/10$256
This Mytrip deal was found by Cheapflights users on 6/11. 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 10/196:00 amYKF - SEA
2 stops11h 09mMultiple Airlines
Thu 10/231:50 pmSEA - YKF
1 stop7h 55mMultiple Airlines
Deal found 6/11$296

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 June 12, 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

Thu 8/28

7:45 pm-12:31 pm

2 stops19h 46m

Seattle/Tacoma Intl

Fri 9/5

1:50 pm-12:45 am

1 stop7h 55m

$256

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Sun 10/19

6:00 am-2:09 pm

2 stops11h 09m

Seattle/Tacoma Intl

Thu 10/23

1:50 pm-12:45 am

1 stop7h 55m

$296

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Sun 7/20

6:00 am-12:31 pm

2 stops33h 31m

$179

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Fri 9/26

6:00 am-2:09 pm

2 stops11h 09m

$200

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/9

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 June 12, 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.

Rainfall in Seattle by month

Plan your trip to Seattle by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Seattle ranges from 0.7 - 6.6 inches per month. November is typically the wettest month, when rainfall can reach 6.6 in. July is typically the driest time to visit Seattle when rainfall is around 0.7 in.

Temperature in Seattle by month

Plan your trip to Seattle by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Seattle, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 66.2 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 41.0 F).

Reviews of airlines servicing Seattle

Get insights into the airlines that provide service to Seattle. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Seattle. Reviews last updated June 12, 2025.
WestJet
7.2
Good
2,868 reviews

Entertainment

6.1

Boarding

7.4

Comfort

7.1

Food

6.2

Overall

7.2

Crew

7.9

Reviews

1 / 20
6.0
Good

Deb,Jan 2025

YYZ - YYC

Boarding went smoothly, you didn't accept debit card for food on flight
WestJet
7.2
Good
2,868 reviews
WestJet
7.2
Good
2,868 reviews

Entertainment

6.1

Boarding

7.4

Comfort

7.1

Food

6.2

Overall

7.2

Crew

7.9

Reviews

1 / 20
6.0
Good

Deb,Jan 2025

YYZ - YYC

Boarding went smoothly, you didn't accept debit card for food on flight

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. 1 airline has flights to Seattle/Tacoma Intl from Toronto Region of Waterloo Intl on a regular basis.

  • What is the cheapest airline to fly from Toronto Region of Waterloo Intl Airport to Seattle round-trip?

    According to our current data, WestJet ($256), offers the cheapest pricing from Toronto Region of Waterloo Intl Airport to Seattle. WestJet is 24% cheaper than the average price of flights available within the next 90 days to this destination.

  • 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 July is currently the most expensive (average of $391). 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 Toronto Region of Waterloo Intl Airport?

Book flights to Toronto Region of Waterloo Intl Airport if you plan to visit one of these locations
SeaTac
Tukwila
Tacoma
Lakewood
Ocean Shores
Lacey
Leavenworth
Federal Way
Lynnwood
Olympia
Shoreline
Kent
Cle Elum
Centralia
Kirkland
Aberdeen
Renton
Shelton
Silverdale
Issaquah

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
Hamilton to Portland flights
Toronto Island to Portland flights
Pearson Intl to Spokane flights

Top airline flying from Region of Waterloo Intl to Seattle

Discover the top airline that operate flights from Region of Waterloo Intl to Seattle. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
WestJetCheapest$141Average$288FlexibilityNo cancel feeOn-time60%

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.