How long is the flight from Region of Ontario to Seattle?

Departing from Region of Ontario to Seattle will take you 11h 27m. The distance from Region of Ontario to Seattle is about 3529 km. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.

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$ 122. Users have also found prices from C$ 153 and C$ 166 on Air Canada and United Airlines, respectively.

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.

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).

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 Hamilton - Seattle/Tacoma Intl or Toronto Island - Seattle/Tacoma Intl.

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

Looking at all options, your cheapest flight can be booked for C$ 380. While the most popular route (Toronto Pearson Intl - Seattle/Tacoma Intl) can be booked for C$ 514 on average, our data indicates C$ 784 when flying from Region of Ontario to Seattle.

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 (100%), Alaska Airlines (87%) or Air Canada (63%) as they are the most reliable in getting you off to your destination on time.

What are the most popular airlines that fly from Region of Ontario to Seattle?

The most popular airlines flying from Region of Ontario to Seattle are WestJet, Air Canada and Alaska Airlines. Something to consider prior to booking your flight.

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.

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.

C$ 323+ Cheap Flights from Ontario to Seattle

Cheap flight deals from Ontario to Seattle

Enter your travel dates to find the best prices.

Cheapest

Best

Direct

Last-minute

One-way

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 5 November 2026.

Wed 9/127:30 a.m. -

1 stop9h 10m

Sun 13/122:30 p.m. -

2 stops12h 15m

Deal found 3/11C$ 496

Thu 10/127:30 a.m. -

1 stop9h 10m

Sun 13/122:30 p.m. -

2 stops12h 15m

Deal found 2/11C$ 497

Wed 2/126:10 a.m. -

1 stop10h 30m

Mon 7/122:30 p.m. -

2 stops12h 15m

Deal found 1/11C$ 500

Wed 16/127:00 a.m. -

2 stops9h 40m

Wed 6/12:30 p.m. -

2 stops12h 15m

Deal found 3/11C$ 503

Wed 16/126:10 a.m. -

1 stop10h 30m

Wed 30/122:30 p.m. -

2 stops12h 15m

Deal found 3/11C$ 505

Tue 15/126:10 a.m. -

1 stop10h 30m

Fri 25/122:30 p.m. -

2 stops12h 15m

Deal found 31/10C$ 507

Wed 16/126:10 a.m. -

1 stop10h 30m

Wed 13/12:30 p.m. -

2 stops12h 15m

Deal found 2/11C$ 508

Tue 15/127:30 a.m. -

1 stop9h 10m

Tue 22/122:30 p.m. -

2 stops12h 15m

Deal found 31/10C$ 512

Tue 1/123:25 p.m. -

1 stop25h 15m

Mon 14/122:30 p.m. -

1 stop20h 55m

Deal found 5/11C$ 628

Tue 24/113:25 p.m. -

1 stop25h 15m

Sat 28/112:20 p.m. -

1 stop21h 05m

Deal found 3/11C$ 638

Sun 22/113:25 p.m. -

1 stop25h 15m

Mon 7/122:30 p.m. -

1 stop20h 55m

Deal found 2/11C$ 641

Wed 9/126:10 a.m. -

1 stop10h 30m

Sat 12/122:20 p.m. -

2 stops30h 20m

Deal found 4/11C$ 649

Best flights from Ontario to Seattle
Discover carefully curated flight deals from Ontario to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated 5 November 2026.

Wed 27/15:30 a.m. -

2 stops35h 10m

Thu 4/22:30 p.m. -

1 stop21h 00m

Deal found 3/11C$ 554

Fri 25/125:15 p.m. -

Nonstop5h 58m

Thu 7/18:29 a.m. -

Nonstop4h 36m

Deal found 4/11C$ 567

Sat 13/26:10 a.m. -

1 stop7h 37m

Sun 21/211:02 p.m. -

1 stop6h 53m

Deal found 2/11C$ 575

Fri 29/19:45 a.m. -

2 stops11h 27m

Mon 1/27:28 p.m. -

2 stops15h 41m

Deal found 3/11C$ 628

Sat 28/1112:10 p.m. -

1 stop11h 49m

Sat 5/1210:10 a.m. -

2 stops9h 22m

Deal found 31/10C$ 704

Sat 5/123:10 p.m. -

1 stop10h 50m

Tue 8/128:40 a.m. -

2 stops12h 46m

Deal found 31/10C$ 725

Tue 12/16:10 a.m. -

1 stop10h 30m

Mon 25/12:30 p.m. -

2 stops30h 10m

Deal found 1/11C$ 593

Fri 12/25:15 p.m. -

1 stop7h 36m

Mon 15/211:02 p.m. -

1 stop6h 53m

Deal found 4/11C$ 595

Sat 26/125:15 p.m. -

Nonstop5h 58m

Wed 6/18:29 a.m. -

Nonstop4h 36m

Deal found 4/11C$ 623

Fri 29/16:10 a.m. -

1 stop10h 30m

Mon 1/26:00 a.m. -

2 stops14h 40m

Deal found 3/11C$ 613

Tue 12/16:15 a.m. -

1 stop8h 43m

Mon 25/17:00 a.m. -

1 stop11h 23m

Deal found 1/11C$ 686

Tue 17/113:25 p.m. -

1 stop25h 15m

Sat 21/115:48 p.m. -

1 stop27h 28m

Deal found 3/11C$ 734

Tue 1/123:25 p.m. -

1 stop25h 15m

Mon 14/122:30 p.m. -

1 stop20h 55m

Deal found 5/11C$ 670

Mon 15/26:10 a.m. -

1 stop11h 30m

Sat 20/212:06 p.m. -

1 stop8h 02m

Deal found 4/11C$ 616

Sat 26/125:15 p.m. -

Nonstop5h 58m

Sun 3/18:33 a.m. -

Nonstop4h 32m

Deal found 4/11C$ 680

Fri 29/16:10 a.m. -

1 stop10h 30m

Mon 1/22:30 p.m. -

1 stop21h 00m

Deal found 1/11C$ 680

Tue 15/125:15 p.m. -

Nonstop5h 41m

Sun 10/18:29 a.m. -

Nonstop4h 36m

Deal found 3/11C$ 716

Thu 17/128:20 a.m. -

1 stop16h 25m

Thu 24/122:30 p.m. -

1 stop12h 05m

Deal found 2/11C$ 849

Sun 2/58:40 p.m. -

1 stop16h 00m

Mon 10/57:20 a.m. -

2 stops9h 30m

Deal found 4/11C$ 715

Tue 22/126:10 a.m. -

1 stop11h 10m

Sat 9/112:00 p.m. -

1 stop8h 14m

Deal found 31/10C$ 733

Sat 26/125:15 p.m. -

Nonstop5h 58m

Thu 31/128:33 a.m. -

Nonstop4h 32m

Deal found 3/11C$ 764

Mon 14/125:30 a.m. -

2 stops35h 10m

Tue 29/122:30 p.m. -

2 stops30h 10m

Deal found 31/10C$ 719

Tue 29/125:15 p.m. -

Nonstop5h 58m

Thu 7/18:29 a.m. -

Nonstop4h 36m

Deal found 31/10C$ 774

Thu 26/113:25 p.m. -

1 stop25h 15m

Sat 28/112:20 p.m. -

1 stop21h 05m

Deal found 1/11C$ 730

Thu 10/127:00 p.m. -

1 stop21h 40m

Sun 13/122:30 p.m. -

1 stop22h 15m

Deal found 2/11C$ 973

Wed 23/125:15 p.m. -

Nonstop5h 58m

Fri 1/18:33 a.m. -

Nonstop4h 32m

Deal found 31/10C$ 782

Wed 9/127:05 a.m. -

1 stop8h 56m

Sun 13/125:54 p.m. -

1 stop20h 33m

Deal found 3/11C$ 976

Sat 19/125:00 a.m. -

1 stop18h 59m

Thu 31/127:05 p.m. -

2 stops12h 01m

Deal found 4/11C$ 1,315

Thu 4/23:25 p.m. -

1 stop25h 15m

Mon 8/22:30 p.m. -

1 stop20h 55m

Deal found 3/11C$ 755

Thu 17/125:30 a.m. -

3 stops33h 13m

Thu 24/1211:15 p.m. -

2 stops12h 27m

Deal found 2/11C$ 1,260

Find flight deals from Ontario to Seattle

Round-trip from	C$ 492
One-way from	C$ 323
Popular in	June
Cheapest in	February
Average price	C$ 669
Good round-trip deal	C$ 718 or less
Good one-way deal	C$ 407 or less

WestJet
27/1-4/2
2 total stops
31h 30m total
Ontario to Seattle

Search Deals

Delta
9/1-31/12
1 total stop
8h 57m total
Ontario to Seattle

Search Deals

Highest demand for flights based on searches. 6% potential increase in price (C$ 52 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 1% potential price decrease (C$ 15 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in November 2026

Search Deals

Price to beat on a round-trip flight from Ontario to Seattle/Tacoma Intl.

Search Deals

Price to beat on a one-way flight from Ontario to Seattle/Tacoma Intl.

Search Deals

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

TorontoSeattle

YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl

YYZSEA

Toronto Pearson Intl

Sat 9/1

6:30 a.m.-12:27 p.m.

1 stop8h 57m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 323

TorontoSeattle

YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl

YYZSEA

Toronto Pearson Intl

Thu 10/12

10:20 p.m.-1:40 p.m.

1 stop18h 20m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 325

TorontoSeattle

YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl

YYZSEA

Toronto Pearson Intl

Sat 5/12

6:00 a.m.-3:03 p.m.

1 stop12h 03m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 328

TorontoSeattle

YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl

YYZSEA

Toronto Pearson Intl

Wed 16/12

10:20 p.m.-1:40 p.m.

2 stops18h 20m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 334

TorontoSeattle

YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl

YYZSEA

Toronto Pearson Intl

Sun 10/1

6:30 a.m.-10:55 a.m.

1 stop7h 25m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 334

TorontoSeattle

YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl

YYZSEA

Toronto Pearson Intl

Fri 18/12

9:45 a.m.-6:43 p.m.

1 stop11h 58m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 334

OttawaSeattle

YOW Ottawa - SEA Seattle/Tacoma Intl

YOWSEA

Ottawa

Tue 16/2

6:10 a.m.-1:40 p.m.

1 stop10h 30m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 345

HamiltonSeattle

YHM Hamilton - SEA Seattle/Tacoma Intl

YHMSEA

Hamilton

Tue 24/11

3:25 p.m.-1:40 p.m.

1 stop25h 15m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 348

TorontoSeattle

YKF Toronto Region of Waterloo Intl - SEA Seattle/Tacoma Intl

YKFSEA

Toronto Region of Waterloo Intl

Mon 30/11

4:30 p.m.-1:40 p.m.

2 stops24h 10m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 353

OttawaSeattle

YOW Ottawa - SEA Seattle/Tacoma Intl

YOWSEA

Ottawa

Sat 5/12

7:50 a.m.-6:22 p.m.

2 stops13h 32m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 356

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/11

Showing 1-10 of 60 resultsSorted by cheapest first

...

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.

YYZ-SEA

YOW-SEA

YHM-SEA

YKF-SEA

YXU-SEA

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

CAON-SEA

YYZ-SEA

YOW-SEA

YHM-SEA

YKF-SEA

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

Currently, February is the cheapest month in which you can book a flight from Region of Ontario to Seattle (average of C$ 352). Flying from Region of Ontario to Seattle in December is currently the most expensive (average of C$ 688). 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?

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

The most flights from CAON to SEA are scheduled on a Wednesday (5 on average). You will have fewer flight options on Friday, which is when the least amount of flights are scheduled (1 on average).

How much does it cost to fly round-trip from Region of Ontario to Seattle?

Airfare is typical for this route at the moment.

Region of Ontario to Seattle flights typically cost between C$ 455 and C$ 715 in January.
The cheapest round-trip price found within the last 5 days was C$ 494 on WestJet (7 Jan-15 Jan).

How far ahead should I book a flight from Region of Ontario to Seattle?

Booking 72 days in advance of your planned departure date is, on average, the best time to get cheap flights from Region of Ontario to Seattle. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

Related info for your journey

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.
How long is the flight from Region of Ontario to Seattle?
Departing from Region of Ontario to Seattle will take you 11h 27m. The distance from Region of Ontario to Seattle is about 3529 km. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.
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$ 122. Users have also found prices from C$ 153 and C$ 166 on Air Canada and United 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 Hamilton - Seattle/Tacoma Intl or Toronto Island - 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 Qatar Airways (100%), Alaska Airlines (87%) or Air Canada (63%) 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$ 380. While the most popular route (Toronto Pearson Intl - Seattle/Tacoma Intl) can be booked for C$ 514 on average, our data indicates C$ 784 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, February is the cheapest month in which you can book a flight from Region of Ontario to Seattle (average of C$ 352). Flying from Region of Ontario to Seattle in December is currently the most expensive (average of C$ 688). 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

SeaTac

Kent

Tukwila

Mukilteo

Ellensburg

Renton

Lynnwood

Cashmere

Tacoma

Marysville

Federal Way

Kirkland

Leavenworth

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Alternative routes for Ontario to Seattle

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Top 5 airlines flying from Ontario to Seattle

Airline	Cheapest	Average	Flexibility	On-time
Delta	CheapestC$ 226	AverageC$ 844	FlexibilityNo cancel fee	On-timeN/A	Search Delta flights
Air Canada	CheapestC$ 252	AverageC$ 670	FlexibilityNo cancel fee	On-time67%	Search Air Canada flights
United Airlines	CheapestC$ 254	AverageC$ 772	FlexibilityNo cancel fee	On-time69%	Search United Airlines flights
Alaska Airlines	CheapestC$ 270	AverageC$ 496	FlexibilityNo cancel fee	On-time75%	Search Alaska Airlines flights
WestJet	CheapestC$ 298	AverageC$ 533	FlexibilityNo cancel fee	On-time60%	Search WestJet flights

Fly with Cheapflights

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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Cheap flights from Ontario to Seattle from C$ 323

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 9/1. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap flight deals from Ontario to Seattle

Cheapest flights from Ontario to SeattleExplore 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 5 November 2026.

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 5 November 2026.

Best flights from Ontario to SeattleDiscover carefully curated flight deals from Ontario to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated 5 November 2026.

Discover carefully curated flight deals from Ontario to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated 5 November 2026.

Direct flights from Ontario to SeattleExplore direct flight options from Ontario to Seattle based on user searches, and compare prices and availability for your desired travel dates. Data last updated 5 November 2026.

Explore direct flight options from Ontario to Seattle based on user searches, and compare prices and availability for your desired travel dates. Data last updated 5 November 2026.

Last-minute flights from Ontario to SeattleDiscover last-minute flight deals from Ontario to Seattle. Data last updated 5 November 2026 and is based on user searches.

Discover last-minute flight deals from Ontario to Seattle. Data last updated 5 November 2026 and is based on user searches.

One-way flights from Ontario to SeattleSearch for one-way flight options from Ontario to Seattle. Find affordable one-way fares based on user searches. Data last updated 5 November 2026.

Search for one-way flight options from Ontario to Seattle. Find affordable one-way fares based on user searches. Data last updated 5 November 2026.

Find flight deals from Ontario to Seattle

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Cheapflights Fare Finder

Use the filters below to find and compare flights from Ontario to Seattle that are best for you.

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.

Cheapflights Insights

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

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 5 November 2026.

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 5 November 2026.

The most flights from CAON to SEA are scheduled on a Wednesday (5 on average). You will have fewer flight options on Friday, which is when the least amount of flights are scheduled (1 on average).

How much does it cost to fly round-trip from Region of Ontario to Seattle?

Airfare is typical for this route at the moment.

Region of Ontario to Seattle flights typically cost between C$ 455 and C$ 715 in January.The cheapest round-trip price found within the last 5 days was C$ 494 on WestJet (7 Jan-15 Jan).

How far ahead should I book a flight from Region of Ontario to Seattle?

Booking 72 days in advance of your planned departure date is, on average, the best time to get cheap flights from Region of Ontario to Seattle. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

Related info for your journey

What airport do you fly into for flights to Seattle from Ontario?

How long is the flight from Region of Ontario to Seattle?

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

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

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

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

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

How can I find direct flights from Ontario to Seattle?

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

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

Travelling to a place near Seattle?

Browse thousands of different options on Cheapflights for your next trip

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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.

Complete your trip

Complete your trip to Seattle by adding a car rental and/or hotel reservation to your travel itinerary.

Direct flights to Washington

Book a non-stop flight to one of these other cities located in Washington.

Search flights from Ontario to Seattle by cabin class

Find flights from Ontario to Seattle, based on your preferred cabin class, be it economy, premium economy, business, or first class.

Ontario and Seattle flights

Browse other Ontario and Seattle flight options. Last updated on 5 November 2026.

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Ontario to Seattle flights

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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 5 November 2026.

Best flights from Ontario to Seattle
Discover carefully curated flight deals from Ontario to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated 5 November 2026.

Direct flights from Ontario to Seattle
Explore direct flight options from Ontario to Seattle based on user searches, and compare prices and availability for your desired travel dates. Data last updated 5 November 2026.

Last-minute flights from Ontario to Seattle
Discover last-minute flight deals from Ontario to Seattle. Data last updated 5 November 2026 and is based on user searches.

One-way flights from Ontario to Seattle
Search for one-way flight options from Ontario to Seattle. Find affordable one-way fares based on user searches. Data last updated 5 November 2026.

Region of Ontario to Seattle flights typically cost between C$ 455 and C$ 715 in January.
The cheapest round-trip price found within the last 5 days was C$ 494 on WestJet (7 Jan-15 Jan).