What is the cheapest airline that flies from Ontario to Seattle/Tacoma Intl?

WestJet, Air Canada, and Alaska Airlines are the most popular carriers operating from Ontario to Seattle/Tacoma Intl

How many flights depart from Region of Ontario to Seattle on average per day?

The number of flights available between Region of Ontario and Seattle is 4 per day as of July 2025. The most frequent departure time is 8:00a.m., with 58% of daily flights leaving at noon.

How many flights depart from Region of Ontario to Seattle on average per week?

The number of flights available between Region of Ontario and Seattle is 33 per week as of July 2025. The most frequent departure day is Wed, with 24% of weekly flights leaving on this day.

Which airlines fly to Seattle?

Air Canada, Alaska Airlines and WestJet are the top three most popular airlines that fly to Seattle from Region of Ontario according to our data. Air Canada is the first choice among our users, with 35% of people opting to fly with this airline when travelling to Seattle. Keep in mind that there are 6 different airlines that fly to Seattle on a routine basis, so you have a few additional options to choose from.

How long does it take to fly to Seattle?

Flight times from Region of Ontario to Seattle vary, but if you’re flying out of Ottawa and flying into Seattle (one of the most popular routes), then the duration is 7h 44m on average. Another popular route from Region of Ontario to Seattle is flying from Toronto to Seattle, which will take roughly 8h 08m. Keep in mind that layovers or delays could extend your travel time.

When did momondo last update prices for flights from Ontario to Seattle/Tacoma Intl Airport?

Prices for flights from Ontario to Seattle/Tacoma Intl Airport are updated daily.

How many operators does momondo search for flights from Ontario to Seattle/Tacoma Intl Airport?

The number of operators available for flights from Ontario to Seattle/Tacoma Intl Airport is 7 as of July 2025.

How old do you have to be to fly from Ontario to Seattle/Tacoma Intl Airport?

The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Ontario to Seattle/Tacoma Intl Airport.

What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?

The travel and health documents you'll need for your trip to Seattle/Tacoma Intl Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Seattle/Tacoma Intl Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

C$ 172 Cheap Flights from Ontario to Seattle in 2025

1 adult

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Find the cheapest flights from Ontario to Seattle

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

4:45 p.m. - 7:08 p.m.YYZ-SEA

5h 23mdirect

7:18 a.m. - 3:00 p.m.SEA-YYZ

4h 42mdirect

C$ 206Alaska Airlines

Find Deal

Wed, 1 Oct - Wed, 8 Oct

4:45 p.m. - 7:08 p.m.YYZ-SEA

5h 23mdirect

7:18 a.m. - 3:00 p.m.SEA-YYZ

4h 42mdirect

C$ 282Alaska Airlines

Find Deal

Tue, 7 Oct - Tue, 21 Oct

8:40 a.m. - 10:59 a.m.YYZ-SEA

5h 19mdirect

10:00 a.m. - 8:30 p.m.SEA-YYZ

7h 30m1 stop

C$ 291Air Canada

Find Deal

Wed, 1 Oct - Tue, 7 Oct

4:45 p.m. - 7:08 p.m.YYZ-SEA

5h 23mdirect

7:18 a.m. - 3:00 p.m.SEA-YYZ

4h 42mdirect

C$ 292Alaska Airlines

Find Deal

Wed, 1 Oct - Sun, 5 Oct

8:30 a.m. - 2:16 p.m.YYZ-SEA

8h 46m1 stop

7:15 p.m. - 6:01 a.m.SEA-YYZ

7h 46m1 stop

C$ 298Air Canada

Find Deal

Tue, 30 Sep - Tue, 7 Oct

12:00 p.m. - 8:29 p.m.YYZ-SEA

11h 29m2 stops

1:50 p.m. - 5:51 a.m.SEA-YYZ

13h 01m2 stops

C$ 309WestJet

Find Deal

Wed, 17 Sep - Wed, 24 Sep

12:00 p.m. - 8:29 p.m.YYZ-SEA

11h 29m2 stops

1:50 p.m. - 12:22 a.m.SEA-YYZ

7h 32m1 stop

C$ 310WestJet

Find Deal

Wed, 17 Sep - Wed, 24 Sep

6:15 a.m. - 12:33 p.m.YKF-SEA

9h 18m1 stop

5:30 a.m. - 5:30 a.m.SEA-YKF

21h 00m3 stops

C$ 419

Find Deal

Sun, 21 Sep - Tue, 30 Sep

6:15 a.m. - 12:33 p.m.YKF-SEA

9h 18m1 stop

2:55 p.m. - 5:30 a.m.SEA-YKF

11h 35m2 stops

C$ 421

Find Deal

Sun, 21 Sep - Tue, 30 Sep

4:05 p.m. - 10:26 p.m.YUL-SEA

9h 21m1 stop

12:46 a.m. - 4:42 p.m.SEA-YUL

12h 56m1 stop

C$ 560American Airlines

Find Deal

Mon, 25 Aug - Mon, 25 Aug

WestJet flights from Region of Ontario to Seattle

Our best WestJet deals on Region of Ontario to Seattle flight tickets

WestJet

17 Sep

YYZ12:00 p.m.Toronto Pearson Intl

11h 29m

2 stops

SEA8:29 p.m.Seattle/Tacoma Intl

24 Sep

SEA1:50 p.m.Seattle/Tacoma Intl

13h 01m

2 stops

YYZ5:51 a.m.Toronto Pearson Intl

C$ 309

Find similar

WestJet

17 Sep

YYZ12:00 p.m.Toronto Pearson Intl

11h 29m

2 stops

SEA8:29 p.m.Seattle/Tacoma Intl

24 Sep

SEA1:50 p.m.Seattle/Tacoma Intl

7h 32m

1 stop

YYZ12:22 a.m.Toronto Pearson Intl

C$ 310

Find similar

WestJet

20 Aug

YYZ3:00 p.m.Toronto Pearson Intl

8h 28m

1 stop

SEA8:28 p.m.Seattle/Tacoma Intl

3 Sep

SEA1:50 p.m.Seattle/Tacoma Intl

7h 32m

1 stop

YYZ12:22 a.m.Toronto Pearson Intl

C$ 313

Find similar

Air Canada flights from Region of Ontario to Seattle

Our best Air Canada deals on Region of Ontario to Seattle flight tickets

Air Canada

1 Oct

YYZ8:40 a.m.Toronto Pearson Intl

5h 19m

SEA10:59 a.m.Seattle/Tacoma Intl

7 Oct

SEA10:00 a.m.Seattle/Tacoma Intl

7h 30m

1 stop

YYZ8:30 p.m.Toronto Pearson Intl

C$ 291

Find similar

Air Canada

30 Sep

YYZ8:30 a.m.Toronto Pearson Intl

8h 46m

1 stop

SEA2:16 p.m.Seattle/Tacoma Intl

7 Oct

SEA7:15 p.m.Seattle/Tacoma Intl

7h 46m

1 stop

YYZ6:01 a.m.Toronto Pearson Intl

C$ 298

Find similar

Air Canada

1 Oct

YYZ8:40 a.m.Toronto Pearson Intl

5h 19m

SEA10:59 a.m.Seattle/Tacoma Intl

5 Oct

SEA2:55 p.m.Seattle/Tacoma Intl

7h 11m

1 stop

YYZ1:06 a.m.Toronto Pearson Intl

C$ 299

Find similar

Fly from

Fly to

Route

Depart

Return

Price

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Wed 1/10

4:45 p.m.-7:08 p.m.

Nonstop5h 23m

Seattle/Tacoma Intl

Wed 8/10

7:18 a.m.-3:00 p.m.

Nonstop4h 42m

C$ 206

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Tue 7/10

4:45 p.m.-7:08 p.m.

Nonstop5h 23m

Seattle/Tacoma Intl

Tue 21/10

7:18 a.m.-3:00 p.m.

Nonstop4h 42m

C$ 282

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Wed 1/10

8:40 a.m.-10:59 a.m.

Nonstop5h 19m

Seattle/Tacoma Intl

Tue 7/10

10:00 a.m.-8:30 p.m.

1 stop7h 30m

C$ 291

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Wed 1/10

4:45 p.m.-7:08 p.m.

Nonstop5h 23m

Seattle/Tacoma Intl

Sun 5/10

7:18 a.m.-3:00 p.m.

Nonstop4h 42m

C$ 292

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Tue 30/9

8:30 a.m.-2:16 p.m.

1 stop8h 46m

Seattle/Tacoma Intl

Tue 7/10

7:15 p.m.-6:01 a.m.

1 stop7h 46m

C$ 298

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Wed 17/9

12:00 p.m.-8:29 p.m.

2 stops11h 29m

Seattle/Tacoma Intl

Wed 24/9

1:50 p.m.-5:51 a.m.

2 stops13h 01m

C$ 309

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Wed 17/9

12:00 p.m.-8:29 p.m.

2 stops11h 29m

Seattle/Tacoma Intl

Wed 24/9

1:50 p.m.-12:22 a.m.

1 stop7h 32m

C$ 310

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Sun 21/9

6:15 a.m.-12:33 p.m.

1 stop9h 18m

Seattle/Tacoma Intl

Tue 30/9

5:30 a.m.-5:30 a.m.

3 stops21h 00m

C$ 419

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Sun 21/9

6:15 a.m.-12:33 p.m.

1 stop9h 18m

Seattle/Tacoma Intl

Tue 30/9

2:55 p.m.-5:30 a.m.

2 stops11h 35m

C$ 421

MontrealSeattle

YUL - SEA

YULSEA

Montreal Pierre Elliott Trudeau Intl

Mon 25/8

4:05 p.m.-10:26 p.m.

1 stop9h 21m

Seattle/Tacoma Intl

Mon 25/8

12:46 a.m.-4:42 p.m.

1 stop12h 56m

C$ 560

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from Region of Ontario to Seattle

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

Other information

What is the cheapest month to fly to Seattle?

If you aren’t able to travel to Seattle during the month of February, then flying in January is also cheap. Prices for this month can be found on momondo for an average of C$ 368.

What is the cheapest day to depart on your flight to Seattle?

Our data shows that Thursday is the least expensive day to fly to Seattle. Tickets to fly out on this day can be as low as C$ 564. If your travel schedule is flexible, try to avoid departing on a Sunday because tickets tend to average around C$ 735. These prices are subject to change though, so be sure to set up a Price Alert for flights to Seattle.

What is the cheapest time of day to depart on your flight to Seattle?

Our most recent data shows that the best time of day to fly to Seattle is in the evening. Flights from Region of Ontario to Seattle during this time can be as low as C$ 479. Flights in the morning are often more expensive with an average ticket price of C$ 827.

What is the cheapest Ontario to Seattle/Tacoma Intl flight route?

Fly from Toronto Pearson Intl to Seattle/Tacoma Intl for the best Ontario - Seattle/Tacoma Intl flight prices

How far in advance should I book a flight to Seattle?

You are more likely to see cheaper flights to Seattle from Region of Ontario when booking weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around C$ 495 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from Region of Ontario for as low as C$ 426 on momondo.

What cabin class options are available on Ontario to Seattle/Tacoma Intl flights?

There are 4 cabin classes available to choose from on Ontario to Seattle/Tacoma Intl flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Region of Ontario to Seattle flights?

You could potentially save up to 21% on your flight if you consider stops on a Region of Ontario to Seattle flight.

Cheap Region of Ontario to Seattle flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Region of Ontario to Seattle

Best price found	C$ 172
Fastest flight time	5h 19m
Direct flights	Every day
Airports in Seattle	1 airport

The best one-way flight to Seattle from Region of Ontario in the past 72 hours is C$ 172. The best round-trip flight deal from Region of Ontario to Seattle found on momondo in the last 72 hours is C$ 206.

The fastest flight from Region of Ontario to Seattle takes 5h 19m

Direct flights go from Region of Ontario to Seattle every day.

There is 1 airport near Seattle: Seattle/Tacoma Intl (SEA)

Search flight deals

When did momondo last update prices for flights from Ontario to Seattle/Tacoma Intl Airport?
Prices for flights from Ontario to Seattle/Tacoma Intl Airport are updated daily.
How many operators does momondo search for flights from Ontario to Seattle/Tacoma Intl Airport?
The number of operators available for flights from Ontario to Seattle/Tacoma Intl Airport is 7 as of July 2025.
How old do you have to be to fly from Ontario to Seattle/Tacoma Intl Airport?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Ontario to Seattle/Tacoma Intl Airport.
What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?
The travel and health documents you'll need for your trip to Seattle/Tacoma Intl Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Seattle/Tacoma Intl Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from Region of Ontario to Seattle?
Based on momondo bookings for flights between Region of Ontario and Seattle, the leading plane model is Airbus A220-300, making up 30.67% of the total bookings. Other popular models include Boeing 737 MAX 8 with 30.44%, Boeing 737-900 Passenger/BBJ3 (winglets) with 12.40%, and Airbus A320-100/200 with 8.98%.

Best airlines flying from Region of Ontario to Seattle

Compare and see reviews for airlines that fly from Region of Ontario to Seattle with momondo

Airline	Rating	Free Cancellation	Price
WestJet	PriceFrom C$ 183	Free Cancellation	Rating 7.2 2,978 reviews	Search WestJet flights
United Airlines	PriceFrom C$ 278	Free Cancellation	Rating 7.4 8,900 reviews	Search United Airlines flights
Alaska Airlines	PriceFrom C$ 331	Free Cancellation	Rating 8.0 10,000 reviews	Search Alaska Airlines flights
Air Canada	PriceFrom C$ 348	Free Cancellation	Rating 7.1 9,851 reviews	Search Air Canada flights
Delta	PriceFrom C$ 374	Free Cancellation	Rating 8.0 7,981 reviews	Search Delta flights
Hawaiian Airlines	PriceFrom C$ 411	Free Cancellation	Rating 7.8 2,611 reviews	Search Hawaiian Airlines flights

Leavenworth

Marysville

Lynnwood

SeaTac

Tacoma

Olympia

Ellensburg

Kirkland

Redmond

Ocean Shores

Shoreline

Tukwila

Renton

Mukilteo

Gig Harbor

Cle Elum

Poulsbo

Puyallup

Centralia

Kent

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to Seattle?

We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from Ontario to Seattle for you.

Can I find flights from Ontario to Seattle with flexible booking policies on momondo?

Yes. momondo enables you to select and highlight flights to Seattle from Ontario with this policy.

How can momondo help me find flights from Ontario to Seattle?

Once you have performed a search for Ontario to Seattle flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

I’m not ready to book a flight from Ontario to Seattle right now. Can momondo alert me if prices change?

If you are not ready to book a flight from Ontario to Seattle now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Seattle and let you know when they change.

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Cheap flights from Ontario to Seattle from C$ 172

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Ontario to Seattle departing on 20/8. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

Big names, great deals

Big names, great deals

Filter for what you want

Filter for what you want

Trusted and free

Trusted and free

Price Alerts

Price Alerts

Find the cheapest flights from Ontario to Seattle

Cheap round-trip flights

Cheap one-way flights

Cheap last-minute flights

Cheap direct flights

WestJet flights from Region of Ontario to Seattle

Our best WestJet deals on Region of Ontario to Seattle flight tickets

Air Canada flights from Region of Ontario to Seattle

Our best Air Canada deals on Region of Ontario to Seattle flight tickets

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

See travel insights to Seattle from

How to get the cheapest flight ticket from Region of Ontario to Seattle

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly to Seattle?

If you aren’t able to travel to Seattle during the month of February, then flying in January is also cheap. Prices for this month can be found on momondo for an average of C$ 368.

What is the cheapest day to depart on your flight to Seattle?

What is the cheapest time of day to depart on your flight to Seattle?

Our most recent data shows that the best time of day to fly to Seattle is in the evening. Flights from Region of Ontario to Seattle during this time can be as low as C$ 479. Flights in the morning are often more expensive with an average ticket price of C$ 827.

What is the cheapest Ontario to Seattle/Tacoma Intl flight route?

Fly from Toronto Pearson Intl to Seattle/Tacoma Intl for the best Ontario - Seattle/Tacoma Intl flight prices

How far in advance should I book a flight to Seattle?

What cabin class options are available on Ontario to Seattle/Tacoma Intl flights?

There are 4 cabin classes available to choose from on Ontario to Seattle/Tacoma Intl flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Region of Ontario to Seattle flights?

You could potentially save up to 21% on your flight if you consider stops on a Region of Ontario to Seattle flight.

What is the cheapest airline that flies from Ontario to Seattle/Tacoma Intl?

WestJet, Air Canada, and Alaska Airlines are the most popular carriers operating from Ontario to Seattle/Tacoma Intl

Which airlines fly to Seattle?

How many flights depart from Region of Ontario to Seattle on average per day?

The number of flights available between Region of Ontario and Seattle is 4 per day as of July 2025. The most frequent departure time is 8:00a.m., with 58% of daily flights leaving at noon.

How many flights depart from Region of Ontario to Seattle on average per week?

The number of flights available between Region of Ontario and Seattle is 33 per week as of July 2025. The most frequent departure day is Wed, with 24% of weekly flights leaving on this day.

How long does it take to fly to Seattle?

Cheap Region of Ontario to Seattle flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Region of Ontario to Seattle

Best price found

Fastest flight time

Direct flights

Airports in Seattle

When did momondo last update prices for flights from Ontario to Seattle/Tacoma Intl Airport?

How many operators does momondo search for flights from Ontario to Seattle/Tacoma Intl Airport?

How old do you have to be to fly from Ontario to Seattle/Tacoma Intl Airport?

What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?

What is the most popular plane model from Region of Ontario to Seattle?

Best airlines flying from Region of Ontario to Seattle

Compare and see reviews for airlines that fly from Region of Ontario to Seattle with momondo

Travelling to a place near Seattle?

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to Seattle?

Can I find flights from Ontario to Seattle with flexible booking policies on momondo?

How can momondo help me find flights from Ontario to Seattle?

I’m not ready to book a flight from Ontario to Seattle right now. Can momondo alert me if prices change?

An easier way to manage your Seattle trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to the United States

Airports servicing Washington