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

WestJet, Delta, and United 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 week?

The number of flights available between Region of Ontario and Seattle is 20 per week as of May 2026. The most frequent departure day is Sat, with 20% of weekly flights leaving on this day.

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 Hamilton and flying into Seattle (one of the most popular routes), then the duration is 8h 15m on average. Another popular route from Region of Ontario to Seattle is flying from Ottawa to Seattle, which will take roughly 8h 25m. Keep in mind that layovers or delays could extend your travel time.

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 2 per day as of May 2026. The most frequent departure time is 6:00p.m., with 78% of daily flights leaving in the evening.

Which airlines fly to Seattle?

Alaska Airlines, Air Canada and WestJet are the top three most popular airlines that fly to Seattle from Region of Ontario according to our data. Alaska Airlines is the first choice among our users, with 34% of people opting to fly with this airline when travelling to Seattle. Keep in mind that there are 5 different airlines that fly to Seattle on a routine basis, so you have a few additional options to choose from.

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 5 as of May 2026.

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$ 225 Cheap Flights from Ontario to Seattle in 2026

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

Enter your travel dates to find the best prices.

12:00 p.m. - 9:00 p.m.

YYZ

SEA

12h 00m

2 stops

10:30 a.m. - 10:45 p.m.

SEA

YYZ

9h 15m

1 stop

C$ 383WestJet

Fri, 19 Jun - Tue, 23 Jun

12:00 p.m. - 6:45 p.m.

YYZ

SEA

9h 45m

2 stops

7:35 p.m. - 6:55 a.m.

SEA

YYZ

8h 20m

1 stop

C$ 388WestJet

Thu, 18 Jun - Mon, 22 Jun

12:00 p.m. - 9:00 p.m.

YYZ

SEA

12h 00m

2 stops

10:30 a.m. - 9:15 p.m.

SEA

YYZ

7h 45m

1 stop

C$ 392WestJet

Fri, 19 Jun - Wed, 24 Jun

12:00 p.m. - 9:00 p.m.

YYZ

SEA

12h 00m

2 stops

7:35 p.m. - 6:55 a.m.

SEA

YYZ

8h 20m

1 stop

C$ 396WestJet

Fri, 19 Jun - Wed, 24 Jun

7:45 a.m. - 2:22 p.m.

YYZ

SEA

9h 37m

2 stops

5:45 a.m. - 7:22 p.m.

SEA

YYZ

10h 37m

2 stops

C$ 412Air Canada

Fri, 19 Jun - Tue, 23 Jun

12:15 p.m. - 7:05 p.m.

YTZ

SEA

9h 50m

1 stop

5:15 p.m. - 10:06 a.m.

SEA

YTZ

13h 51m

1 stop

C$ 528United Airlines

Tue, 16 Jun - Thu, 25 Jun

4:05 p.m. - 9:04 p.m.

YQG

SEA

7h 59m

1 stop

8:00 a.m. - 7:07 p.m.

SEA

YQG

8h 07m

1 stop

C$ 610Air Canada

Thu, 15 Oct - Mon, 19 Oct

4:05 p.m. - 9:04 p.m.

YQG

SEA

7h 59m

1 stop

8:00 a.m. - 7:07 p.m.

SEA

YQG

8h 07m

1 stop

C$ 611Air Canada

Thu, 15 Oct - Mon, 19 Oct

12:15 p.m. - 9:10 p.m.

YTZ

SEA

11h 55m

2 stops

5:15 p.m. - 10:06 a.m.

SEA

YTZ

13h 51m

1 stop

C$ 633United Airlines

Tue, 16 Jun - Wed, 24 Jun

12:15 p.m. - 6:52 p.m.

YTZ

SEA

9h 37m

1 stop

8:10 a.m. - 6:42 p.m.

SEA

YTZ

7h 32m

1 stop

C$ 659United Airlines

Tue, 29 Sep - Sat, 3 Oct

Air Canada flights from Region of Ontario to Seattle

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

Air Canada

19 Jun

YYZ7:45 a.m.Toronto Pearson Intl

9h 37m

2 stops

SEA2:22 p.m.Seattle/Tacoma Intl

23 Jun

SEA5:45 a.m.Seattle/Tacoma Intl

10h 37m

2 stops

YYZ7:22 p.m.Toronto Pearson Intl

C$ 412

Air Canada

19 Jun

YYZ7:45 a.m.Toronto Pearson Intl

9h 37m

2 stops

SEA2:22 p.m.Seattle/Tacoma Intl

24 Jun

SEA5:45 a.m.Seattle/Tacoma Intl

10h 37m

2 stops

YYZ7:22 p.m.Toronto Pearson Intl

C$ 426

Air Canada

19 Jun

YYZ7:45 a.m.Toronto Pearson Intl

9h 37m

2 stops

SEA2:22 p.m.Seattle/Tacoma Intl

23 Jun

SEA3:00 p.m.Seattle/Tacoma Intl

14h 35m

2 stops

YYZ8:35 a.m.Toronto Pearson Intl

C$ 452

United Airlines flights from Region of Ontario to Seattle

Our best United Airlines deals on Region of Ontario to Seattle flight tickets

United Airlines

11 Jun

YYZ5:16 p.m.Toronto Pearson Intl

11h 13m

1 stop

SEA1:29 a.m.Seattle/Tacoma Intl

13 Jun

SEA7:05 a.m.Seattle/Tacoma Intl

13h 54m

2 stops

YYZ11:59 p.m.Toronto Pearson Intl

C$ 436

United Airlines

25 Jun

YYZ11:00 a.m.Toronto Pearson Intl

8h 09m

1 stop

SEA4:09 p.m.Seattle/Tacoma Intl

8 Jul

SEA5:15 p.m.Seattle/Tacoma Intl

13h 39m

1 stop

YYZ9:54 a.m.Toronto Pearson Intl

C$ 504

United Airlines

25 Jun

YYZ11:00 a.m.Toronto Pearson Intl

8h 09m

1 stop

SEA4:09 p.m.Seattle/Tacoma Intl

8 Jul

SEA5:15 p.m.Seattle/Tacoma Intl

13h 39m

1 stop

YYZ9:54 a.m.Toronto Pearson Intl

C$ 505

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Fri 19/6

12:00 p.m.-9:00 p.m.

2 stops12h 00m

Seattle/Tacoma Intl

Tue 23/6

10:30 a.m.-10:45 p.m.

1 stop9h 15m

C$ 383

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Thu 18/6

12:00 p.m.-6:45 p.m.

2 stops9h 45m

Seattle/Tacoma Intl

Mon 22/6

7:35 p.m.-6:55 a.m.

1 stop8h 20m

C$ 388

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Fri 19/6

12:00 p.m.-9:00 p.m.

2 stops12h 00m

Seattle/Tacoma Intl

Wed 24/6

10:30 a.m.-9:15 p.m.

1 stop7h 45m

C$ 392

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Fri 19/6

12:00 p.m.-9:00 p.m.

2 stops12h 00m

Seattle/Tacoma Intl

Wed 24/6

7:35 p.m.-6:55 a.m.

1 stop8h 20m

C$ 396

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Fri 19/6

7:45 a.m.-2:22 p.m.

2 stops9h 37m

Seattle/Tacoma Intl

Tue 23/6

5:45 a.m.-7:22 p.m.

2 stops10h 37m

C$ 412

TorontoSeattle

YTZ - SEA

YTZSEA

Toronto Island

Tue 16/6

12:15 p.m.-7:05 p.m.

1 stop9h 50m

Seattle/Tacoma Intl

Thu 25/6

5:15 p.m.-10:06 a.m.

1 stop13h 51m

C$ 528

Quickest round-trip

WindsorSeattle

YQG - SEA

YQGSEA

Windsor

Thu 15/10

4:05 p.m.-9:04 p.m.

1 stop7h 59m

Seattle/Tacoma Intl

Mon 19/10

8:00 a.m.-7:07 p.m.

1 stop8h 07m

C$ 610

WindsorSeattle

YQG - SEA

YQGSEA

Windsor

Thu 15/10

4:05 p.m.-9:04 p.m.

1 stop7h 59m

Seattle/Tacoma Intl

Mon 19/10

8:00 a.m.-7:07 p.m.

1 stop8h 07m

C$ 611

TorontoSeattle

YTZ - SEA

YTZSEA

Toronto Island

Tue 16/6

12:15 p.m.-9:10 p.m.

2 stops11h 55m

Seattle/Tacoma Intl

Wed 24/6

5:15 p.m.-10:06 a.m.

1 stop13h 51m

C$ 633

TorontoSeattle

YTZ - SEA

YTZSEA

Toronto Island

Tue 29/9

12:15 p.m.-6:52 p.m.

1 stop9h 37m

Seattle/Tacoma Intl

Sat 3/10

8:10 a.m.-6:42 p.m.

1 stop7h 32m

C$ 659

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 January, then flying in December is also cheap. Prices for this month can be found on momondo for an average of C$ 120.

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$ 532. If your travel schedule is flexible, try to avoid departing on a Monday because tickets tend to average around C$ 829. 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$ 512. Flights in the morning are often more expensive with an average ticket price of C$ 1,047.

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 from Ontario 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$ 473 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$ 379 on momondo.

What cabin class options are available on Region of Ontario to Seattle flights?

There are 4 cabin classes available to choose from on Region of Ontario to Seattle 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 40% 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$ 333
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$ 333. The best round-trip flight deal from Region of Ontario to Seattle found on momondo in the last 72 hours is C$ 712.

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 in Seattle. From Region of Ontario there are direct flights to Seattle/Tacoma Intl (SEA).

Search flight deals

Frequently asked questions about flying from Ontario to Seattle

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 5 as of May 2026.
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 51.33% of the total bookings. Other popular models include Boeing 737 MAX 9 with 21.35%, Boeing 787-9 Dreamliner with 4.11%, and Boeing 777-300ER with 3.98%.

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
United Airlines	PriceFrom C$ 251	Free Cancellation	Rating 7.4 9,766 reviews	Search United Airlines flights
Alaska Airlines	PriceFrom C$ 270	Free Cancellation	Rating 7.9 12,433 reviews	Search Alaska Airlines flights
WestJet	PriceFrom C$ 271	Free Cancellation	Rating 7.2 3,350 reviews	Search WestJet flights
Air Canada	PriceFrom C$ 272	Free Cancellation	Rating 7.1 11,105 reviews	Search Air Canada flights
Delta	PriceFrom C$ 293	Free Cancellation	Rating 7.9 8,417 reviews	Search Delta flights

Lynnwood

Leavenworth

SeaTac

Redmond

Marysville

Kirkland

Woodinville

Tacoma

Puyallup

Tukwila

Olympia

Ocean Shores

Ellensburg

Federal Way

Bainbridge Island

Gig Harbor

Renton

Kent

Edmonds

Centralia

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$ 225

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 19/6. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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Air Canada flights from Region of Ontario to Seattle

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

What is the cheapest month to fly to Seattle?

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?

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

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

What cabin class options are available on Region of Ontario to Seattle flights?

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

What is the cheapest airline that flies 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?

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

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

Frequently asked questions about flying from 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?

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

Fly your favourite airline to Seattle

Airlines are sorted and displayed according to clicks in the past 7 days on momondo

Cabin classes currently available on flights to Seattle

List of cabin classes available on flights landing in Seattle. Availability may vary depending on flight origin and airline.

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