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

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

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

55 flights are operational weekly from Seattle to Region of Ontario as of July 2025. The most popular departure day for this route is Thu, with 18% of flights per week taking off on this day.

What airlines fly to Region of Ontario?

Alaska Airlines, Air Canada and WestJet are the top three most popular airlines that fly to Region of Ontario from Seattle according to our data. Alaska Airlines is the first choice among our users, with 42% of people opting to fly with this airline when traveling to Region of Ontario. Keep in mind that there are 5 different airlines that fly to Region of Ontario on a routine basis, so you have a few additional options to choose from.

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

The number of flights available between Seattle and Region of Ontario is 7 per day as of July 2025. The most frequent departure time is 7:00AM, with 60% of daily flights leaving at noon.

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

Prices for flights from Seattle/Tacoma Intl Airport to Ontario are refreshed on a daily basis.

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

The number of operators available for flights from Seattle/Tacoma Intl Airport to Ontario is 6 as of July 2025.

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

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 Seattle/Tacoma Intl Airport to Ontario.

What documentation or ID do you need to fly to Ontario?

The travel and health documents you'll need for your trip to Ontario 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 Ontario. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

$96 Cheap Flights from Seattle to Ontario in 2025

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Find the cheapest flights from Seattle to Ontario

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

1:15 pm - 12:31 amSEA-YYZ

8h 16m1 stop

6:45 am - 12:33 pmYYZ-SEA

8h 48m1 stop

$226WestJet

Find Deal

Fri, Sep 19 - Sun, Sep 21

10:00 am - 9:51 pmSEA-YYZ

8h 51m1 stop

8:40 am - 10:59 amYYZ-SEA

5h 19mnonstop

$227Air Canada

Find Deal

Sat, Sep 13 - Sun, Sep 21

7:15 pm - 9:45 amSEA-YTZ

11h 30m2 stops

4:10 pm - 10:16 pmYTZ-SEA

9h 06m2 stops

$237Air Canada

Find Deal

Sat, Sep 13 - Sun, Sep 21

10:00 am - 7:50 pmSEA-YYZ

6h 50m1 stop

8:00 am - 6:36 pmYYZ-SEA

13h 36m1 stop

$241Air Canada

Find Deal

Sat, Sep 13 - Sun, Sep 21

7:35 pm - 6:12 amSEA-YYZ

7h 37m1 stop

12:00 pm - 8:29 pmYYZ-SEA

11h 29m2 stops

$242WestJet

Find Deal

Wed, Aug 27 - Wed, Sep 3

7:35 pm - 6:12 amSEA-YYZ

7h 37m1 stop

12:00 pm - 7:14 pmYYZ-SEA

10h 14m2 stops

$243WestJet

Find Deal

Tue, Aug 26 - Tue, Sep 2

7:16 am - 3:00 pmSEA-YYZ

4h 44mnonstop

4:45 pm - 7:08 pmYYZ-SEA

5h 23mnonstop

$269Alaska Airlines

Find Deal

Tue, Sep 9 - Tue, Sep 16

12:05 pm - 11:16 pmSEA-YUL

8h 11m1 stop

6:00 am - 2:44 pmYUL-SEA

11h 44m1 stop

$409Delta

Find Deal

Wed, Sep 3 - Wed, Sep 10

11:54 pm - 3:02 pmSEA-YXU

12h 08m2 stops

6:15 am - 10:59 amYXU-SEA

7h 44m1 stop

$490United Airlines

Find Deal

Tue, Aug 26 - Tue, Sep 2

4:55 pm - 5:07 pmSEA-YXU

21h 12m2 stops

9:55 am - 8:42 pmYXU-SEA

13h 47m2 stops

$505United Airlines

Find Deal

Tue, Aug 26 - Tue, Sep 2

WestJet flights from Seattle to Region of Ontario

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

WestJet

Sep 19

SEA1:15 pmSeattle/Tacoma Intl

8h 16m

1 stop

YYZ12:31 amToronto Pearson Intl

Sep 21

YYZ6:45 amToronto Pearson Intl

8h 48m

1 stop

SEA12:33 pmSeattle/Tacoma Intl

$226

Find similar

WestJet

Aug 27

SEA7:35 pmSeattle/Tacoma Intl

7h 37m

1 stop

YYZ6:12 amToronto Pearson Intl

Sep 3

YYZ12:00 pmToronto Pearson Intl

11h 29m

2 stops

SEA8:29 pmSeattle/Tacoma Intl

$242

Find similar

WestJet

Aug 26

SEA7:35 pmSeattle/Tacoma Intl

7h 37m

1 stop

YYZ6:12 amToronto Pearson Intl

Sep 2

YYZ12:00 pmToronto Pearson Intl

10h 14m

2 stops

SEA7:14 pmSeattle/Tacoma Intl

$243

Find similar

Air Canada flights from Seattle to Region of Ontario

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

Air Canada

Sep 13

SEA10:00 amSeattle/Tacoma Intl

8h 51m

1 stop

YYZ9:51 pmToronto Pearson Intl

Sep 21

YYZ8:40 amToronto Pearson Intl

5h 19m

SEA10:59 amSeattle/Tacoma Intl

$227

Find similar

Air Canada

Sep 13

SEA7:15 pmSeattle/Tacoma Intl

11h 30m

2 stops

YTZ9:45 amToronto Island

Sep 21

YTZ4:10 pmToronto Island

9h 06m

2 stops

SEA10:16 pmSeattle/Tacoma Intl

$237

Find similar

Air Canada

Sep 13

SEA10:00 amSeattle/Tacoma Intl

6h 50m

1 stop

YYZ7:50 pmToronto Pearson Intl

Sep 21

YYZ8:00 amToronto Pearson Intl

13h 36m

1 stop

SEA6:36 pmSeattle/Tacoma Intl

$241

Find similar

Fly from

Fly to

Route

Depart

Return

Price

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Fri 9/19

1:15 pm-12:31 am

1 stop8h 16m

Toronto Pearson Intl

Sun 9/21

6:45 am-12:33 pm

1 stop8h 48m

$226

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Sat 9/13

10:00 am-9:51 pm

1 stop8h 51m

Toronto Pearson Intl

Sun 9/21

8:40 am-10:59 am

Nonstop5h 19m

$227

SeattleToronto

SEA - YTZ

SEAYTZ

Seattle/Tacoma Intl

Sat 9/13

7:15 pm-9:45 am

2 stops11h 30m

Toronto Island

Sun 9/21

4:10 pm-10:16 pm

2 stops9h 06m

$237

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Sat 9/13

10:00 am-7:50 pm

1 stop6h 50m

Toronto Pearson Intl

Sun 9/21

8:00 am-6:36 pm

1 stop13h 36m

$241

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Wed 8/27

7:35 pm-6:12 am

1 stop7h 37m

Toronto Pearson Intl

Wed 9/3

12:00 pm-8:29 pm

2 stops11h 29m

$242

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Tue 8/26

7:35 pm-6:12 am

1 stop7h 37m

Toronto Pearson Intl

Tue 9/2

12:00 pm-7:14 pm

2 stops10h 14m

$243

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Tue 9/9

7:16 am-3:00 pm

Nonstop4h 44m

Toronto Pearson Intl

Tue 9/16

4:45 pm-7:08 pm

Nonstop5h 23m

$269

SeattleMontreal

SEA - YUL

SEAYUL

Seattle/Tacoma Intl

Wed 9/3

12:05 pm-11:16 pm

1 stop8h 11m

Montreal Pierre Elliott Trudeau Intl

Wed 9/10

6:00 am-2:44 pm

1 stop11h 44m

$409

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Tue 8/26

11:54 pm-3:02 pm

2 stops12h 08m

London

Tue 9/2

6:15 am-10:59 am

1 stop7h 44m

$490

SeattleLondon

SEA - YXU

SEAYXU

Seattle/Tacoma Intl

Tue 8/26

4:55 pm-5:07 pm

2 stops21h 12m

London

Tue 9/2

9:55 am-8:42 pm

2 stops13h 47m

$505

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

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 Region of Ontario?

The month of January is, on average, the cheapest month to fly to Region of Ontario from Seattle, with most prices found around $282. If you aren’t able to travel during the month of January, then book flights to Region of Ontario from Seattle during February instead. Flights to Region of Ontario in February, while not as cheap as those in January, still average around $286.

What is the cheapest day to depart on your flight to Region of Ontario?

According to our data, Tuesday is the cheapest day to fly to Region of Ontario from Seattle. The lowest ticket price found for a Tuesday departure recently was $562. Keep in mind that prices can always vary depending on your route and whether or not you are flying domestic or international. Flights from Seattle to Region of Ontario on a Saturday will generally be more expensive and average around $696. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

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

According to our data, the cheapest time of day to fly to Region of Ontario is in the afternoon. momondo users have found flights departing from Seattle to Region of Ontario in the afternoon for as low as $283. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights in the morning are often more expensive with an average ticket price of $627.

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

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

How far in advance should I book a flight to Region of Ontario?

You are more likely to see cheaper flights to Region of Ontario from Seattle when booking weeks ahead of your departure date. In general, you can expect to find flights to Region of Ontario for around $420 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Region of Ontario from Seattle for as low as $292 on momondo.

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

There are 4 cabin classes available to choose from on Seattle/Tacoma Intl to Ontario 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 Seattle to Region of Ontario flights?

You could potentially save up to 41% on your flight if you consider stops on a Seattle to Region of Ontario flight.

Cheap Seattle to Region of Ontario flight deals and tips

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

Best Price Found	$96
Fastest flight time	4h 42m
Direct flights	Every day
Airports in Region of Ontario	7 airports

The best one-way flight to Region of Ontario from Seattle in the past 72 hours is $96. The best round-trip flight deal from Seattle to Region of Ontario found on momondo in the last 72 hours is $226.

The fastest flight from Seattle to Region of Ontario takes 4h 42m

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

There are 7 airports near Region of Ontario: Ottawa (YOW), Montreal Pierre Elliott Trudeau Intl (YUL), London (YXU), Toronto Pearson Intl (YYZ), Thunder Bay (YQT), Toronto Island (YTZ), Hamilton (YHM)

Search flight deals

When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to Ontario?
Prices for flights from Seattle/Tacoma Intl Airport to Ontario are refreshed on a daily basis.
How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to Ontario?
The number of operators available for flights from Seattle/Tacoma Intl Airport to Ontario is 6 as of July 2025.
How old do you have to be to fly from Seattle/Tacoma Intl Airport to Ontario?
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 Seattle/Tacoma Intl Airport to Ontario.
What documentation or ID do you need to fly to Ontario?
The travel and health documents you'll need for your trip to Ontario 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 Ontario. 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 Seattle to Region of Ontario?
momondo data reveals that the most frequently booked plane model on the route from Seattle to Region of Ontario is Boeing 737 MAX 8, representing 36.78% of all bookings. The subsequent popular models are Airbus A220-300 at 22.80%, Boeing 737-900 Passenger/BBJ3 (winglets) at 8.21%, and Airbus A320-100/200 at 5.78%.

Best airlines flying from Seattle to Region of Ontario

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

Airline	Rating	Free Cancellation	Price
Air Canada	PriceFrom $128	Free Cancellation	Rating 7.1 9,851 reviews	Search Air Canada flights
United Airlines	PriceFrom $158	Free Cancellation	Rating 7.4 8,900 reviews	Search United Airlines flights
Delta	PriceFrom $186	Free Cancellation	Rating 8.0 7,981 reviews	Search Delta flights
WestJet	PriceFrom $236	Free Cancellation	Rating 7.2 2,978 reviews	Search WestJet flights
Alaska Airlines	PriceFrom $273	Free Cancellation	Rating 8.0 10,000 reviews	Search Alaska Airlines flights

Why use momondo?

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

momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from Seattle to Ontario. Millions of users trust and use momondo every year so you are in good hands.

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

Yes. All flights to Ontario from Seattle on momondo can be compared and filtered by various policies on offer, including flexible booking.

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

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Ontario from Seattle.

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

Of course. momondo tracks the price of Seattle to Ontario flights. All you need is a valid email address and we will do the rest; it is that quick and easy.

An easier way to manage your Region of Ontario 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.

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Find better results for your trip to Ontario

Popular cities in Ontario

Flights to Torontofrom $98

Flights to Vancouverfrom $79

Flights to Montrealfrom $155

Flights to Calgaryfrom $145

Flights to Ottawafrom $185

Flights to Halifaxfrom $168

Flights to Winnipegfrom $194

Flights to Québec Cityfrom $226

Flights to Saskatoonfrom $120

Flights to Kelownafrom $202

Flights to St. John'sfrom $263

Flights to Reginafrom $219

Cheap flights from Seattle to Ontario from $96

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Seattle to Ontario departing on 10/22. 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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Big names and deals

Filter for what you want

Filter for what you want

Trusted and free

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Find the cheapest flights from Seattle to Ontario

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WestJet flights from Seattle to Region of Ontario

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

Air Canada flights from Seattle to Region of Ontario

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

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

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 Region of Ontario?

What is the cheapest day to depart on your flight to Region of Ontario?

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

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

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

How far in advance should I book a flight to Region of Ontario?

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

There are 4 cabin classes available to choose from on Seattle/Tacoma Intl to Ontario 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 Seattle to Region of Ontario flights?

You could potentially save up to 41% on your flight if you consider stops on a Seattle to Region of Ontario flight.

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

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

What airlines fly to Region of Ontario?

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

The number of flights available between Seattle and Region of Ontario is 7 per day as of July 2025. The most frequent departure time is 7:00AM, with 60% of daily flights leaving at noon.

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

55 flights are operational weekly from Seattle to Region of Ontario as of July 2025. The most popular departure day for this route is Thu, with 18% of flights per week taking off on this day.

Cheap Seattle to Region of Ontario flight deals and tips

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

Best Price Found

Fastest flight time

Direct flights

Airports in Region of Ontario

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

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

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

What documentation or ID do you need to fly to Ontario?

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

Best airlines flying from Seattle to Region of Ontario

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

Why use momondo?

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

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

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

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

An easier way to manage your Region of Ontario 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 Ontario

Popular cities in Ontario

Popular flights according to clicks in the last 7 days on momondo