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Cheap flights from Ontario to Seattle from C$ 202

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 14/5. Fares are subject to change and may not be available on all flights or dates of travel.
YYZ — SEA
31 Mar — 7 Apr1
1 adult

Cheap flight deals from Ontario to Seattle

Keep the following information in mind while searching for Ontario to Seattle flight deals. Data was last updated 26 March 2025.

Round-trip from

C$ 342

One-way from

C$ 202

Popular in

May

Cheapest in

February

Average price

C$ 511

Good round-trip deal

C$ 514 or less

Good one-way deal

C$ 318 or less
WestJet
  • WestJet
  • 1/6-4/6
  • 2 total stops
  • 15h 59m total
  • Ontario to Seattle
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WestJet
  • WestJet
  • 14/5
  • 1 total stop
  • 9h 58m total
  • Ontario to Seattle
Search Deals
Highest demand for flights based on searches. 13% potential increase in price (C$ 121 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease (C$ 18 potential savings vs. average RT price).
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Average for round-trip flights in March 2025
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Price to beat on a round-trip flight from Ontario to Seattle/Tacoma Intl.
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Price to beat on a one-way flight from Ontario to Seattle/Tacoma Intl.
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Find flight deals from Ontario to Seattle

Cheapest flights from Ontario to Seattle
Explore the most affordable flight options available from Ontario to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 26 March 2025.

Sun 1/67:50 a.m.YOW - SEA
1 stop8h 08mWestJet
Wed 4/61:50 p.m.SEA - YOW
1 stop7h 51mWestJet
Deal found 25/3C$ 342
Tue 27/56:00 a.m.YHM - SEA
1 stop9h 58mWestJet
Sat 31/51:50 p.m.SEA - YHM
1 stop7h 51mWestJet
Deal found 25/3C$ 342
Fri 16/51:30 p.m.YYZ - SEA
1 stop9h 58mWestJet
Fri 23/57:05 a.m.SEA - YYZ
1 stop8h 49mWestJet
Deal found 25/3C$ 346
Thu 17/76:00 a.m.YKF - SEA
1 stop9h 58mWestJet
Sun 20/72:05 p.m.SEA - YKF
1 stop7h 41mWestJet
Deal found 25/3C$ 348
Sun 13/44:00 p.m.YYZ - SEA
1 stop25h 21mMultiple Airlines
Tue 15/412:30 p.m.SEA - YYZ
1 stop15h 13mMultiple Airlines
Deal found 25/3C$ 390
Thu 24/47:20 p.m.YYZ - SEA
Nonstop5h 21mAir Canada
Wed 30/46:00 a.m.SEA - YYZ
Nonstop4h 57mAir Canada
Deal found 26/3C$ 415
Mon 5/56:00 a.m.YOW - SEA
1 stop9h 58mMultiple Airlines
Thu 8/57:05 a.m.SEA - YOW
2 stops14h 16mMultiple Airlines
Deal found 25/3C$ 418
Thu 24/44:45 p.m.YYZ - SEA
Nonstop5h 14mAlaska Airlines
Sun 27/47:15 a.m.SEA - YYZ
Nonstop4h 45mAlaska Airlines
Deal found 26/3C$ 428
Sat 24/512:25 p.m.YTZ - SEA
1 stop10h 12mAir Canada
Wed 28/57:20 a.m.SEA - YTZ
1 stop9h 30mAir Canada
Deal found 25/3C$ 433
Thu 24/47:20 p.m.YYZ - SEA
Nonstop5h 21mSWISS
Wed 30/411:45 p.m.SEA - YYZ
1 stop13h 57mSWISS
Deal found 26/3C$ 436
Tue 15/44:45 p.m.YYZ - SEA
Nonstop5h 20mHawaiian Airlines
Sat 19/47:20 a.m.SEA - YYZ
Nonstop4h 40mHawaiian Airlines
Deal found 25/3C$ 439
Sun 4/58:30 a.m.YYZ - SEA
Nonstop5h 21mUnited Airlines
Tue 6/57:00 a.m.SEA - YYZ
1 stop9h 37mUnited Airlines
Deal found 24/3C$ 458

Cheapflights Fare Finder

Customize your flight search to find flights from Ontario 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 26 March 2025.
Use the filters below to find and compare flights from Ontario to Seattle that are best for you.

Fly from

Ontario

Fly to

Seattle

Route

Depart

Return

Price

OttawaSeattle

YOW - SEA

YOWSEA

Ottawa

Sun 1/6

7:50 a.m.-12:58 p.m.

1 stop8h 08m

Seattle/Tacoma Intl

Wed 4/6

1:50 p.m.-12:41 a.m.

1 stop7h 51m

C$ 342

HamiltonSeattle

YHM - SEA

YHMSEA

Hamilton

Tue 27/5

6:00 a.m.-12:58 p.m.

1 stop9h 58m

Seattle/Tacoma Intl

Sat 31/5

1:50 p.m.-12:41 a.m.

1 stop7h 51m

C$ 342

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Fri 16/5

1:30 p.m.-8:28 p.m.

1 stop9h 58m

Seattle/Tacoma Intl

Fri 23/5

7:05 a.m.-6:54 p.m.

1 stop8h 49m

C$ 346

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Thu 17/7

6:00 a.m.-12:58 p.m.

1 stop9h 58m

Seattle/Tacoma Intl

Sun 20/7

2:05 p.m.-12:46 a.m.

1 stop7h 41m

C$ 348

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Sun 13/4

4:00 p.m.-2:21 p.m.

1 stop25h 21m

Seattle/Tacoma Intl

Tue 15/4

12:30 p.m.-6:43 a.m.

1 stop15h 13m

C$ 390

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Thu 24/4

7:20 p.m.-9:41 p.m.

Nonstop5h 21m

Seattle/Tacoma Intl

Wed 30/4

6:00 a.m.-1:57 p.m.

Nonstop4h 57m

C$ 415

OttawaSeattle

YOW - SEA

YOWSEA

Ottawa

Mon 5/5

6:00 a.m.-12:58 p.m.

1 stop9h 58m

Seattle/Tacoma Intl

Thu 8/5

7:05 a.m.-12:21 a.m.

2 stops14h 16m

C$ 418

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Thu 24/4

4:45 p.m.-6:59 p.m.

Nonstop5h 14m

Seattle/Tacoma Intl

Sun 27/4

7:15 a.m.-3:00 p.m.

Nonstop4h 45m

C$ 428

TorontoSeattle

YTZ - SEA

YTZSEA

Toronto Island

Sat 24/5

12:25 p.m.-7:37 p.m.

1 stop10h 12m

Seattle/Tacoma Intl

Tue 3/6

7:20 a.m.-7:50 p.m.

1 stop9h 30m

C$ 433

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Thu 24/4

7:20 p.m.-9:41 p.m.

Nonstop5h 21m

Seattle/Tacoma Intl

Wed 30/4

11:45 p.m.-4:42 p.m.

1 stop13h 57m

C$ 436

Flights are sorted by cheapest round-trip flights first.

Deals found on 25/3

Showing 1-10 of 50 results
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Best time to book a flight from Ontario to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Ontario 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 Ontario to Seattle

What is the cheapest month to book a flight from Region of Ontario to Seattle?

Currently, January is the cheapest month in which you can book a flight from Region of Ontario to Seattle (average of C$ 261). Flying from Region of Ontario to Seattle in December is currently the most expensive (average of C$ 353). 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.

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

Find hourly flight availability from Ontario 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 26 March 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Region of Ontario to Seattle as you normally would.

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 18.0 - 168.0 mm per month. November is typically the wettest month, when rainfall can reach 168.0 mm. July is typically the driest time to visit Seattle when rainfall is around 18.0 mm.

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 19.0 C. Travellers hoping to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 5.0 C).

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 26 March 2025.
Read reviews from past customers who have flown Alaska Airlines, Delta and Hawaiian Airlines from Ontario to Seattle. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
9,789 reviews
Check prices

Food

7.1

Overall

8.0

Comfort

7.9

Crew

8.5

Entertainment

7.1

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Alaska Airlines
8.0
Very good
9,789 reviews
Alaska Airlines
8.0
Very good
9,789 reviews
Check prices

Food

7.1

Overall

8.0

Comfort

7.9

Crew

8.5

Entertainment

7.1

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Delta
8.0
Very good
7,891 reviews
Alaska Airlines
8.0
Very good
9,789 reviews
Check prices

Food

7.1

Overall

8.0

Comfort

7.9

Crew

8.5

Entertainment

7.1

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Hawaiian Airlines
7.9
Good
2,334 reviews
Alaska Airlines
8.0
Very good
9,789 reviews
Check prices

Food

7.1

Overall

8.0

Comfort

7.9

Crew

8.5

Entertainment

7.1

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
SWISS
7.5
Good
1,569 reviews
Alaska Airlines
8.0
Very good
9,789 reviews
Check prices

Food

7.1

Overall

8.0

Comfort

7.9

Crew

8.5

Entertainment

7.1

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
United Airlines
7.4
Good
8,608 reviews
Alaska Airlines
8.0
Very good
9,789 reviews
Check prices

Food

7.1

Overall

8.0

Comfort

7.9

Crew

8.5

Entertainment

7.1

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Related info for your journey

Find useful and relevant information for your journey from Ontario 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 Ontario?

    Located just 18.4 km from the city centre, Seattle/Tacoma Intl (SEA) is the airport most travelers will use when flying to Seattle from Ontario.

  • What are the cheapest airlines to fly from Region of Ontario to Seattle one-way?

    For one-way options, check prices for WestJet. According to our data, you can fly for as low as C$ 202. Users have also found prices from C$ 237 and C$ 250 on Air Canada and Alaska Airlines, respectively.

  • What are the most popular routes from Region of Ontario to Seattle?

    The most popular route from Region of Ontario to Seattle is Toronto Pearson Intl - Seattle/Tacoma Intl. You may also consider Montreal Pierre Elliott Trudeau Intl - Seattle/Tacoma Intl or Toronto Region of Waterloo Intl - Seattle/Tacoma Intl.

  • What are the most reliable airlines from Region of Ontario to Seattle?

    No one likes to see their flight delayed. When booking a flight from Region of Ontario to Seattle consider choosing Air Tahiti Nui (100%), Qatar Airways (85%) or Alaska Airlines (85%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Region of Ontario to Seattle?

    Looking at all options, your cheapest flight can be booked for C$ 258. While the most popular route (Toronto Pearson Intl - Seattle/Tacoma Intl) can be booked for C$ 378 on average our data indicates C$ 1,681 when flying from Region of Ontario to Seattle.

  • Can I find deals for flights from Ontario to Seattle that include hotel bookings?

    Yes. In addition to deals on Ontario to Seattle flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to Seattle?

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

  • Can I find deals for business class flights from Ontario to Seattle?

    Yes. Cheapflights offers flight deals from Ontario 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 Region of Ontario to Seattle?

    Currently, January is the cheapest month in which you can book a flight from Region of Ontario to Seattle (average of C$ 261). Flying from Region of Ontario to Seattle in December is currently the most expensive (average of C$ 353). 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

Travelling to a place near Ontario?

Book flights to Ontario if you plan to visit one of these locations
SeaTac
Tukwila
Marysville
Bothell
Leavenworth
Tacoma
Olympia
Lynnwood

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Alternative routes for Ontario to Seattle

See prices for flight routes from nearby airports that may be better suited for you.
Pearson Intl to Seattle flights
Pierre Elliott Trudeau Intl to Seattle flights
Calgary to Seattle flights
Edmonton to Seattle flights
Vancouver Intl to Seattle flights
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Region of Waterloo Intl to Seattle flights
Hamilton to Seattle flights
Kelowna to Seattle flights
Toronto Island to Seattle flights
Pearson Intl to Portland flights
Calgary to Portland flights
Victoria to Seattle flights
Ottawa to Seattle flights
Pierre Elliott Trudeau Intl to Portland flights
Halifax to Seattle flights
Edmonton to Portland flights
Québec City to Seattle flights
Winnipeg to Seattle flights
Region of Waterloo Intl to Portland flights
Vancouver Intl to Spokane flights
Hamilton to Portland flights
Pearson Intl to Spokane flights
Winnipeg to Portland flights
Saskatoon to Seattle flights
Edmonton to Spokane flights
Toronto Island to Portland flights
Ottawa to Portland flights
Prince George to Seattle flights
Victoria to Portland flights
Calgary to Spokane flights
Kelowna to Portland flights
Regina to Seattle flights
Fort St. John to Portland flights
Vancouver Intl to Bellingham flights
Québec City to Portland flights
Campbell River to Seattle flights
Regina to Portland flights
Pearson Intl to Pasco flights
Medicine Hat to Seattle flights
London to Seattle flights
Fort St. John to Spokane flights
Pierre Elliott Trudeau Intl to Spokane flights

Top 6 airlines flying from Ontario to Seattle

Discover the top 6 airlines that operate flights from Ontario 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 629,999 searches. Data last updated 26 March 2025.
AirlineCheapestAverageFlexibilityOn-time
WestJetCheapestC$ 306AverageC$ 559FlexibilityNo cancel feeOn-time60%
Search WestJet flights
Alaska AirlinesCheapestC$ 343AverageC$ 555FlexibilityNo cancel feeOn-time75%
Search Alaska Airlines flights
Air CanadaCheapestC$ 374AverageC$ 596FlexibilityNo cancel feeOn-time67%
Search Air Canada flights
United AirlinesCheapestC$ 378AverageC$ 657FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
DeltaCheapestC$ 418AverageC$ 616FlexibilityNo cancel feeOn-timeN/A
Search Delta flights
American AirlinesCheapestC$ 443AverageC$ 571FlexibilityNo cancel feeOn-time71%
Search American Airlines flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travelers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Ontario to Seattle?

900+ travel sites are searched through when a user searches for a flight using Cheapflights. From the search interface, users can use filters to choose airlines, airports, flight times, cabin classes and more to their preference. Book your flight to Seattle from Ontario today with Cheapflights!

Why should you use Cheapflights to find cheap flight tickets from Ontario to Seattle?

Millions of users choose and trust Cheapflights to book the best flight deals from Ontario to Seattle for free. We help you search and compare prices from hundreds of airlines for the right flight just for you.

Can Cheapflights find flights from Ontario to Seattle with no change fees?

Need flexible booking options for your flight to Seattle from Ontario? Don’t worry, Cheapflights have you covered. Use our search filter to only show flights with no change fees.

Can Cheapflights notify me if prices for flights from Ontario to Seattle become cheaper?

Of course! You can now track prices for flights from Ontario to Seattle and get an alert from Cheapflights when they change. Have a valid email address ready and click the bell icon next to the flight deals above to set up your price alerts.

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