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$147+ Cheap flights from Ontario 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 3/19. Fares are subject to change and may not be available on all flights or dates of travel.
YYZ — SEA
Feb 25 — Mar 41
Tue 2/25
Tue 3/4
1 adult, Economy
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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 February 20, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$233
(Mytrip)

One-way from

$147
(Air Canada)

Popular in

May

Cheapest in

January

Average price

$266

Good round-trip deal

$250 or less

Good one-way deal

$182 or less
Provider with most accurate pricing for Toronto (YTO)-Seattle/Tacoma Intl flight deals.
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Provider most trusted by Cheapflights users for Toronto (YTO)-Seattle/Tacoma Intl flights.
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From Ontario to Seattle/Tacoma Intl
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One-way flight from Ontario to Seattle/Tacoma Intl
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Highest demand for flights based on searches. 14% potential increase in price ($69 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($8 potential savings vs. average RT price).
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Average for round-trip flights in February 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 February 20, 2025.

This Mytrip deal was found by Cheapflights users on 2/19. 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.
Thu 3/207:25 pmYYZ - SEA
1 stop16h 18mMultiple Airlines
Tue 3/258:04 pmSEA - YYZ
2 stops30h 51mMultiple Airlines
Deal found 2/19$233
This Air Canada deal was found by Cheapflights users on 2/19. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/207:05 pmYYZ - SEA
Nonstop5h 25mAir Canada
Tue 3/256:05 amSEA - YYZ
Nonstop4h 45mAir Canada
Deal found 2/19$242
This United Airlines deal was found by Cheapflights users on 2/19. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/87:05 pmYYZ - SEA
Nonstop5h 21mUnited Airlines
Tue 4/156:05 amSEA - YYZ
Nonstop4h 55mUnited Airlines
Deal found 2/19$243
This Trip.com deal was found by Cheapflights users on 2/20. 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.
Thu 3/134:20 pmYYZ - SEA
Nonstop5h 24mAlaska Airlines
Wed 3/197:15 amSEA - YYZ
Nonstop4h 40mAlaska Airlines
Deal found 2/20$248
This Booking.com deal was found by Cheapflights users on 2/19. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/84:20 pmYTZ - SEA
2 stops8h 43mAir Canada
Tue 4/155:45 amSEA - YTZ
2 stops11h 05mAir Canada
Deal found 2/19$260
This Vakatrip deal was found by Cheapflights users on 2/19. 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 Vakatrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/141:30 pmYYZ - SEA
1 stop9h 58mWestJet
Thu 6/127:05 amSEA - YYZ
2 stops10h 58mWestJet
Deal found 2/19$262
This Delta deal was found by Cheapflights users on 2/19. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/812:14 pmYYZ - SEA
1 stop13h 20mDelta
Mon 4/1412:40 amSEA - YYZ
1 stop7h 54mDelta
Deal found 2/19$274
This American Airlines deal was found by Cheapflights users on 2/20. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/265:14 pmYYZ - SEA
1 stop10h 34mAmerican Airlines
Sun 3/3011:14 pmSEA - YYZ
1 stop8h 01mAmerican Airlines
Deal found 2/20$288
This Flysmarter deal was found by Cheapflights users on 2/19. 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 Flysmarter is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/1312:35 pmYYZ - SEA
2 stops11h 21mBritish Airways
Wed 3/1911:14 pmSEA - YYZ
1 stop8h 01mBritish Airways
Deal found 2/19$290
This Kiwi.com deal was found by Cheapflights users on 2/19. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/49:30 pmYKF - SEA
1 stop20h 04mMultiple Airlines
Wed 4/911:30 amSEA - YKF
2 stops10h 46mMultiple Airlines
Deal found 2/19$293
This Kiwi.com deal was found by Cheapflights users on 2/19. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/36:30 amYKF - SEA
2 stops30h 30mWestJet
Wed 4/93:15 pmSEA - YKF
1 stop7h 01mWestJet
Deal found 2/19$296
This Mytrip deal was found by Cheapflights users on 2/19. 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.
Tue 3/181:30 pmYUL - SEA
3 stops22h 13mMultiple Airlines
Tue 3/259:48 amSEA - YUL
3 stops35h 51mMultiple Airlines
Deal found 2/19$299

Find flights from Ontario to Seattle within your budget

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 2,558,603 searches. Data last updated February 20, 2025.

Fly from

Ontario

Fly to

Seattle

Route

Depart

Return

Price

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Thu 3/20

7:25 pm-8:43 am

1 stop16h 18m

Seattle/Tacoma Intl

Tue 3/25

8:04 pm-5:55 am

2 stops30h 51m

$233

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Thu 3/20

7:05 pm-9:30 pm

Nonstop5h 25m

Seattle/Tacoma Intl

Tue 3/25

7:05 pm-6:09 am

1 stop8h 04m

$242

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Tue 4/8

7:05 pm-9:26 pm

Nonstop5h 21m

Seattle/Tacoma Intl

Tue 4/15

6:05 am-2:00 pm

Nonstop4h 55m

$243

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Thu 3/13

4:20 pm-6:44 pm

Nonstop5h 24m

Seattle/Tacoma Intl

Wed 3/19

7:15 am-2:55 pm

Nonstop4h 40m

$248

TorontoSeattle

YTZ - SEA

YTZSEA

Toronto Island

Tue 4/8

4:20 pm-10:03 pm

2 stops8h 43m

Seattle/Tacoma Intl

Tue 4/15

5:45 am-7:50 pm

2 stops11h 05m

$260

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Wed 5/14

1:30 pm-8:28 pm

1 stop9h 58m

Seattle/Tacoma Intl

Thu 6/12

7:05 am-9:03 pm

2 stops10h 58m

$262

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Tue 4/8

12:14 pm-10:34 pm

1 stop13h 20m

Seattle/Tacoma Intl

Mon 4/14

12:40 am-11:34 am

1 stop7h 54m

$274

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Wed 3/26

5:14 pm-12:48 am

1 stop10h 34m

Seattle/Tacoma Intl

Sun 3/30

11:14 pm-10:15 am

1 stop8h 01m

$288

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Thu 3/13

12:35 pm-8:56 pm

2 stops11h 21m

Seattle/Tacoma Intl

Wed 3/19

11:14 pm-10:15 am

1 stop8h 01m

$290

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Fri 4/4

9:30 pm-2:34 pm

1 stop20h 04m

Seattle/Tacoma Intl

Wed 4/9

11:30 am-1:16 am

2 stops10h 46m

$293

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/19

Showing 1-10 of 49 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.

Travel insights for flights from Ontario to Seattle

Get recent, data-driven insights about flights from Ontario to Seattle including ideal travel times, pricing trends, and more.

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 $238). Flying from Region of Ontario to Seattle in July is currently the most expensive (average of $411). 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 February 20, 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.

Weekly flight availability from Region of Ontario to Seattle

Explore weekly flight availability from Ontario to Seattle. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated February 20, 2025.

The most flights from CAON to SEA are scheduled on a Monday (5 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (3 on average).

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 February 20, 2025.
Read reviews from past customers who have flown Alaska Airlines, Delta and Austrian 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
9,697 reviews

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Crew

8.5

Food

7.1

Overall

8.0

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
9,697 reviews
Alaska Airlines
8.0
Very good
9,697 reviews

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Crew

8.5

Food

7.1

Overall

8.0

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
8,219 reviews
Alaska Airlines
8.0
Very good
9,697 reviews

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Crew

8.5

Food

7.1

Overall

8.0

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

Austrian Airlines
7.6
Good
773 reviews
Alaska Airlines
8.0
Very good
9,697 reviews

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Crew

8.5

Food

7.1

Overall

8.0

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
8,765 reviews
Alaska Airlines
8.0
Very good
9,697 reviews

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Crew

8.5

Food

7.1

Overall

8.0

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

American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
9,697 reviews

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Crew

8.5

Food

7.1

Overall

8.0

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?

    Seattle/Tacoma Intl (SEA), located 11.4 mi from the city center, is the airport you fly into when you book flights from Ontario to Seattle.

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

    $147 is the cheapest one-way deal found within the past few days, from Air Canada. You may also be able to find cheap deals on Alaska Airlines and WestJet, with prices starting from $153 and $155, respectively.

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

    When deciding which route to take from Region of Ontario to Seattle consider Toronto Pearson Intl - Seattle/Tacoma Intl, Montreal Pierre Elliott Trudeau Intl - Seattle/Tacoma Intl or Ottawa - Seattle/Tacoma Intl as they are the most popular.

  • 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 Alaska Airlines (82%), Hawaiian Airlines (82%) or Qatar Airways (69%) 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?

    On average you can expect to pay $277 for a flight from Region of Ontario to Seattle. The cheapest flight overall is $144 while the most popular route, (Toronto Pearson Intl - Seattle/Tacoma Intl) is currently priced at $190.

  • 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 $238). Flying from Region of Ontario to Seattle in July is currently the most expensive (average of $411). 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 Ontario?

Book flights to Ontario if you plan to visit one of these locations
SeaTac
Tukwila
Renton
Tacoma
Lacey
Ocean Shores
Leavenworth
Olympia
Federal Way
Centralia
Marysville
Cle Elum
Mukilteo
Aberdeen
Lakewood
Issaquah
Shoreline
Lynnwood
Shelton
Silverdale

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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.
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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 2,558,603 searches. Data last updated February 20, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$139Average$504FlexibilityNo cancel feeOn-time67%
WestJetCheapest$163Average$442FlexibilityNo cancel feeOn-time60%
United AirlinesCheapest$240Average$479FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$246Average$419FlexibilityNo cancel feeOn-time75%
DeltaCheapest$292Average$464FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$402Average$695FlexibilityNo cancel feeOn-time71%
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