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Cheap flights from Toronto Region of Waterloo Intl Airport to Seattle from C$ 258

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 9/11. Fares are subject to change and may not be available on all flights or dates of travel.
YKF — SEA
10 Jul — 17 Jul1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Region of Waterloo Intl to Seattle

Enter your travel dates to find the best prices.

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 10 June 2026.

Wed 8/78:40 p.m.
YKF
-
SEA
1 stop25h 05m
WestJet
Wed 15/77:00 a.m.
SEA
-
YKF
1 stop9h 50m
WestJet
Deal found 10/6C$ 510
Tue 7/78:40 p.m.
YKF
-
SEA
1 stop27h 20m
WestJet
Sat 18/77:00 a.m.
SEA
-
YKF
1 stop9h 50m
WestJet
Deal found 9/6C$ 516
Wed 8/78:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Fri 17/77:00 a.m.
SEA
-
YKF
1 stop9h 50m
WestJet
Deal found 10/6C$ 517
Mon 10/88:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Thu 20/87:35 p.m.
SEA
-
YKF
1 stop21h 15m
WestJet
Deal found 10/6C$ 522
Fri 17/78:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Mon 20/77:00 a.m.
SEA
-
YKF
1 stop9h 50m
WestJet
Deal found 9/6C$ 523
Sun 16/88:40 p.m.
YKF
-
SEA
1 stop25h 05m
WestJet
Sat 29/87:00 a.m.
SEA
-
YKF
1 stop9h 50m
WestJet
Deal found 7/6C$ 524
Thu 13/88:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Mon 24/87:35 p.m.
SEA
-
YKF
1 stop21h 15m
WestJet
Deal found 10/6C$ 528
Thu 13/88:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Sat 22/87:35 p.m.
SEA
-
YKF
1 stop21h 15m
WestJet
Deal found 9/6C$ 531
Sun 16/88:40 p.m.
YKF
-
SEA
1 stop25h 05m
WestJet
Sun 30/87:00 a.m.
SEA
-
YKF
1 stop9h 50m
WestJet
Deal found 8/6C$ 534
Fri 17/78:40 p.m.
YKF
-
SEA
1 stop27h 20m
WestJet
Wed 22/77:00 a.m.
SEA
-
YKF
1 stop9h 50m
WestJet
Deal found 7/6C$ 535
Tue 23/68:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Sun 28/67:00 a.m.
SEA
-
YKF
1 stop9h 50m
WestJet
Deal found 9/6C$ 540
Mon 6/78:40 p.m.
YKF
-
SEA
1 stop16h 00m
WestJet
Tue 7/77:35 p.m.
SEA
-
YKF
1 stop21h 15m
WestJet
Deal found 9/6C$ 541

Find 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 10 June 2026.

Round-trip from

C$ 510

One-way from

C$ 272

Popular in

June

Cheapest in

February

Average price

C$ 658
WestJet
  • WestJet
  • 8/7-15/7
  • 2 total stops
  • 34h 55m total
  • Toronto to Seattle
Search Deals
WestJet
  • WestJet
  • 5/7
  • 1 total stop
  • 16h 00m total
  • Toronto to Seattle
Search Deals
Highest demand for flights based on searches. 14% potential increase in price (C$ 114 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease (C$ 23 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 2026
Search Deals

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 629,999 searches. Data last updated 10 June 2026.
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

Fly to

Route

Depart

Return

Price

Cheapest round-trip

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Fri 24/7

8:40 p.m.-9:00 p.m.

1 stop27h 20m

Seattle/Tacoma Intl

Sun 26/7

7:00 a.m.-7:50 p.m.

1 stop9h 50m

C$ 517

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Thu 23/7

8:40 p.m.-6:45 p.m.

1 stop25h 05m

Seattle/Tacoma Intl

Sun 26/7

7:00 a.m.-7:50 p.m.

1 stop9h 50m

C$ 535

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Fri 17/7

8:40 p.m.-9:00 p.m.

1 stop27h 20m

Seattle/Tacoma Intl

Wed 22/7

7:00 a.m.-7:50 p.m.

1 stop9h 50m

C$ 535

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Sun 5/7

8:40 p.m.-9:40 a.m.

1 stop16h 00m

Seattle/Tacoma Intl

Tue 7/7

7:35 p.m.-7:50 p.m.

1 stop21h 15m

C$ 549

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Fri 10/7

8:40 p.m.-9:40 a.m.

1 stop16h 00m

Seattle/Tacoma Intl

Sun 19/7

7:35 p.m.-7:50 p.m.

1 stop21h 15m

C$ 579

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Thu 10/9

8:40 p.m.-9:40 a.m.

1 stop16h 00m

Seattle/Tacoma Intl

Mon 14/9

7:35 p.m.-7:50 p.m.

1 stop21h 15m

C$ 583

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Wed 22/7

8:40 p.m.-6:45 p.m.

1 stop25h 05m

Seattle/Tacoma Intl

Tue 11/8

7:00 a.m.-7:50 p.m.

1 stop9h 50m

C$ 584

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Fri 14/8

8:40 p.m.-9:40 a.m.

1 stop16h 00m

Seattle/Tacoma Intl

Mon 17/8

7:35 p.m.-7:50 p.m.

1 stop21h 15m

C$ 584

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Sun 28/6

8:40 p.m.-9:40 a.m.

1 stop16h 00m

Seattle/Tacoma Intl

Wed 8/7

7:35 p.m.-7:50 p.m.

1 stop21h 15m

C$ 584

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Wed 22/7

8:40 p.m.-9:00 p.m.

1 stop27h 20m

Seattle/Tacoma Intl

Fri 7/8

7:00 a.m.-7:50 p.m.

1 stop9h 50m

C$ 584

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/6

Showing 1-10 of 22 resultsSorted by cheapest first
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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.

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?

    Seattle/Tacoma Intl (SEA) is the airport you will fly into if you book a flight from Toronto Region of Waterloo Intl to Seattle. You should not have trouble finding flights to Seattle/Tacoma Intl from Toronto Region of Waterloo Intl; the airport handles an average of 0 inbound flights from Toronto Region of Waterloo Intl per day. You should also have plenty of airline options to choose from since 0 airlines have flights to the Seattle airport from Toronto Region of Waterloo Intl. It is only a 18.4 km journey from Seattle/Tacoma Intl (SEA) to Seattle’s city centre.

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

    Departing from Toronto Region of Waterloo Intl Airport to Seattle will take you 27h 20m. The distance between Toronto Region of Waterloo Intl Airport and Seattle is about 3257 km.

  • 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.

See more FAQs

Travelling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
SeaTac
Kent
Leavenworth
Mukilteo
Tacoma
Renton
Cashmere
Tukwila
Olympia
Marysville
Kirkland

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Users can book flights with no change fees policies with our dedicated filters. Book flights from Region of Waterloo Intl to Seattle flexibly with Cheapflights today.

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