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$145+ 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 2/11. Fares are subject to change and may not be available on all flights or dates of travel.
YYZ — SEA
Jan 26 — Feb 21
Sun 1/26
Sun 2/2
1 adult, Economy
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Cheap flight deals from Ontario to Seattle

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (CAON) 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 January 21, 2025.

Round-trip from

$241
(United Airlines)

One-way from

$145
(Kiwi.com)

Good round-trip deal

$263 or less

Good one-way deal

$192 or less
From Ontario to Seattle/Tacoma Intl
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One-way flight from Ontario to Seattle/Tacoma Intl
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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 January 21, 2025.

This Trip.com deal was found by Cheapflights users on 1/20. 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 5/18:00 amYYZ - SEA
1 stop8h 08mWestJet
Sat 5/102:05 pmSEA - YYZ
2 stops12h 46mWestJet
Deal found 1/20$234
This Kiwi.com deal was found by Cheapflights users on 1/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/218:00 pmYYZ - SEA
1 stop16h 30mMultiple Airlines
Mon 3/2411:42 amSEA - YYZ
1 stop16h 01mMultiple Airlines
Deal found 1/20$237
This Alaska Airlines deal was found by Cheapflights users on 1/19. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/114:20 pmYYZ - SEA
Nonstop5h 23mAlaska Airlines
Tue 2/187:18 amSEA - YYZ
Nonstop4h 37mAlaska Airlines
Deal found 1/19$241
This Trip.com deal was found by Cheapflights users on 1/21. 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.
Wed 3/266:15 amYOW - SEA
1 stop11h 06mWestJet
Thu 3/2711:30 amSEA - YOW
2 stops10h 14mWestJet
Deal found 1/21$242
This United Airlines deal was found by Cheapflights users on 1/20. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/47:05 pmYYZ - SEA
Nonstop5h 25mUnited Airlines
Wed 3/1212:55 pmSEA - YYZ
1 stop8h 27mUnited Airlines
Deal found 1/20$242
This Air Canada deal was found by Cheapflights users on 1/20. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/112:25 pmYTZ - SEA
1 stop10h 12mAir Canada
Fri 5/97:20 amSEA - YTZ
1 stop9h 30mAir Canada
Deal found 1/20$257
This Trip.com deal was found by Cheapflights users on 1/20. 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.
Wed 3/196:15 amYOW - SEA
1 stop11h 06mMultiple Airlines
Fri 4/43:15 pmSEA - YOW
2 stops22h 15mMultiple Airlines
Deal found 1/20$260
This Air Canada deal was found by Cheapflights users on 1/21. 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 2/278:00 amYYZ - SEA
1 stop9h 30mAir Canada
Fri 2/287:05 pmSEA - YYZ
1 stop8h 04mAir Canada
Deal found 1/21$261
This Kissandfly.com deal was found by Cheapflights users on 1/21. 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 Kissandfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/137:05 pmYYZ - SEA
Nonstop5h 25mLufthansa
Wed 2/193:24 pmSEA - YYZ
1 stop13h 06mLufthansa
Deal found 1/21$268
This Delta deal was found by Cheapflights users on 1/20. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/205:00 pmYYZ - SEA
1 stop10h 09mDelta
Sun 3/2312:49 amSEA - YYZ
1 stop9h 44mDelta
Deal found 1/20$294
This Mytrip deal was found by Cheapflights users on 1/20. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/106:30 amYKF - SEA
1 stop10h 51mWestJet
Wed 4/163:15 pmSEA - YKF
1 stop7h 01mWestJet
Deal found 1/20$298
This Kiwi.com deal was found by Cheapflights users on 1/21. 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.
Tue 3/116:05 pmYHM - SEA
1 stop23h 16mWestJet
Tue 3/1811:30 amSEA - YHM
2 stops26h 43mWestJet
Deal found 1/21$319

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 January 21, 2025.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Fri 3/21

8:00 pm-9:30 am

1 stop16h 30m

Seattle/Tacoma Intl

Mon 3/24

11:42 am-6:43 am

1 stop16h 01m

$237

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Mon 4/21

7:55 am-2:21 pm

1 stop9h 26m

Seattle/Tacoma Intl

Fri 5/2

2:05 pm-5:51 am

2 stops12h 46m

$240

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Tue 2/11

4:20 pm-6:43 pm

Nonstop5h 23m

Seattle/Tacoma Intl

Tue 2/18

7:18 am-2:55 pm

Nonstop4h 37m

$241

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Tue 3/4

7:05 pm-9:30 pm

Nonstop5h 25m

Seattle/Tacoma Intl

Wed 3/12

12:55 pm-12:22 am

1 stop8h 27m

$242

OttawaSeattle

YOW - SEA

YOWSEA

Ottawa

Wed 3/26

6:15 am-2:21 pm

1 stop11h 06m

Seattle/Tacoma Intl

Thu 3/27

11:30 am-12:44 am

2 stops10h 14m

$242

OttawaSeattle

YOW - SEA

YOWSEA

Ottawa

Wed 3/19

6:15 am-2:21 pm

1 stop11h 06m

Seattle/Tacoma Intl

Fri 4/4

3:15 pm-4:30 pm

2 stops22h 15m

$260

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Thu 2/27

8:00 am-2:30 pm

1 stop9h 30m

Seattle/Tacoma Intl

Fri 2/28

7:05 pm-6:09 am

1 stop8h 04m

$261

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Thu 2/13

7:05 pm-9:30 pm

Nonstop5h 25m

Seattle/Tacoma Intl

Wed 2/19

3:24 pm-7:30 am

1 stop13h 06m

$268

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Thu 3/20

5:00 pm-12:09 am

1 stop10h 09m

Seattle/Tacoma Intl

Sun 3/23

12:49 am-1:33 pm

1 stop9h 44m

$294

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Thu 4/10

6:30 am-2:21 pm

1 stop10h 51m

Seattle/Tacoma Intl

Wed 4/16

3:15 pm-1:16 am

1 stop7h 01m

$298

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/20

Showing 1-10 of 51 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 January 21, 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 January 21, 2025.

The most flights from CAON to SEA are scheduled on a Monday (4 on average). You will have fewer flight options on Wednesday, 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 January 21, 2025.
Read reviews from past customers who have flown Delta, Air Canada and United 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
9,706 reviews

Comfort

7.9

Crew

8.5

Food

7.1

Overall

8.0

Boarding

8.2

Entertainment

7.1

Reviews

1 / 10

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
9,706 reviews
Alaska Airlines
8.0
Very good
9,706 reviews

Comfort

7.9

Crew

8.5

Food

7.1

Overall

8.0

Boarding

8.2

Entertainment

7.1

Reviews

1 / 10

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
8,521 reviews
Alaska Airlines
8.0
Very good
9,706 reviews

Comfort

7.9

Crew

8.5

Food

7.1

Overall

8.0

Boarding

8.2

Entertainment

7.1

Reviews

1 / 10

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
8,984 reviews
Alaska Airlines
8.0
Very good
9,706 reviews

Comfort

7.9

Crew

8.5

Food

7.1

Overall

8.0

Boarding

8.2

Entertainment

7.1

Reviews

1 / 10

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

Brussels Airlines
7.4
Good
349 reviews
Alaska Airlines
8.0
Very good
9,706 reviews

Comfort

7.9

Crew

8.5

Food

7.1

Overall

8.0

Boarding

8.2

Entertainment

7.1

Reviews

1 / 10

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
9,706 reviews

Comfort

7.9

Crew

8.5

Food

7.1

Overall

8.0

Boarding

8.2

Entertainment

7.1

Reviews

1 / 10

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?

    $146 is the cheapest one-way deal found within the past few days, from United Airlines. You may also be able to find cheap deals on WestJet and Alaska Airlines, with prices starting from $149 and $151, 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 Qatar Airways (88%), Alaska Airlines (82%) or Hawaiian Airlines (82%) 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 $388 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 $233.

  • 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
Federal Way
Ocean Shores
Leavenworth
Olympia
Marysville
Centralia
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 January 21, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$139Average$510FlexibilityNo cancel feeOn-time67%
WestJetCheapest$163Average$445FlexibilityNo cancel feeOn-time60%
United AirlinesCheapest$243Average$513FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$246Average$416FlexibilityNo cancel feeOn-time75%
DeltaCheapest$292Average$472FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$402Average$695FlexibilityNo cancel feeOn-time71%
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