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

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

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 47% 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 4 per day as of June 2026. The most frequent departure time is 8:00AM, with 100% of daily flights leaving at noon.

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

30 flights are operational weekly from Seattle to Region of Ontario as of June 2026. The most popular departure day for this route is Wed, with 17% of flights per week taking off on this day.

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 5 as of June 2026.

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.

$160 Cheap Flights from Seattle to Ontario in 2026

Discover deals from 900+ travel sites with momondo.

Find the cheapest flights from Seattle to Ontario

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

Enter your travel dates to find the best prices.

7:35 pm - 5:45 am

SEA

YYZ

7h 10m

1 stop

1:30 pm - 6:45 pm

YYZ

SEA

8h 15m

1 stop

$342WestJet

Sun, Sep 13 - Thu, Sep 17

7:35 pm - 5:45 am

SEA

YYZ

7h 10m

1 stop

1:30 pm - 6:45 pm

YYZ

SEA

8h 15m

1 stop

$346WestJet

Fri, Sep 11 - Sun, Sep 13

7:35 pm - 5:45 am

SEA

YYZ

7h 10m

1 stop

1:30 pm - 6:45 pm

YYZ

SEA

8h 15m

1 stop

$348WestJet

Thu, Oct 15 - Tue, Oct 20

7:35 pm - 5:45 am

SEA

YYZ

7h 10m

1 stop

1:30 pm - 6:45 pm

YYZ

SEA

8h 15m

1 stop

$349WestJet

Fri, Oct 16 - Tue, Oct 20

7:35 pm - 5:45 am

SEA

YYZ

7h 10m

1 stop

1:30 pm - 6:45 pm

YYZ

SEA

8h 15m

1 stop

$356WestJet

Tue, Oct 13 - Tue, Oct 20

5:50 am - 8:35 pm

SEA

YUL

11h 45m

2 stops

2:15 pm - 10:42 pm

YUL

SEA

11h 27m

2 stops

$401Air Canada

Thu, Aug 13 - Wed, Aug 19

10:30 am - 12:25 am

SEA

YUL

10h 55m

2 stops

5:30 pm - 10:42 pm

YUL

SEA

8h 12m

1 stop

$409Multiple Airlines

Thu, Aug 13 - Wed, Aug 19

7:45 am - 10:28 pm

SEA

YTS

11h 43m

1 stop

5:15 am - 2:37 pm

YTS

SEA

12h 22m

2 stops

$627Air Canada

Sat, Oct 31 - Wed, Nov 4

8:40 am - 10:33 am

SEA

YTS

22h 53m

2 stops

5:15 am - 2:37 pm

YTS

SEA

12h 22m

2 stops

$632Air Canada

Sat, Oct 31 - Wed, Nov 4

7:45 am - 10:28 pm

SEA

YTS

11h 43m

1 stop

10:10 am - 8:54 pm

YTS

SEA

13h 44m

1 stop

$646Air Canada

Sat, Oct 31 - Wed, Nov 4

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WestJet flights from Seattle to Region of Ontario

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

WestJet

Sep 19

SEA7:35 pmSeattle/Tacoma Intl

8h 20m

1 stop

YYZ6:55 amToronto Pearson Intl

Sep 21

YYZ1:30 pmToronto Pearson Intl

8h 15m

1 stop

SEA6:45 pmSeattle/Tacoma Intl

$341

WestJet

Sep 13

SEA7:35 pmSeattle/Tacoma Intl

7h 10m

1 stop

YYZ5:45 amToronto Pearson Intl

Sep 17

YYZ1:30 pmToronto Pearson Intl

8h 15m

1 stop

SEA6:45 pmSeattle/Tacoma Intl

$342

WestJet

Sep 11

SEA7:35 pmSeattle/Tacoma Intl

7h 10m

1 stop

YYZ5:45 amToronto Pearson Intl

Sep 13

YYZ1:30 pmToronto Pearson Intl

8h 15m

1 stop

SEA6:45 pmSeattle/Tacoma Intl

$346

Delta flights from Seattle to Region of Ontario

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

Delta

Jun 30

SEA9:45 amSeattle/Tacoma Intl

10h 43m

1 stop

YUL11:28 pmMontreal Pierre Elliott Trudeau Intl

Jul 4

YUL12:47 pmMontreal Pierre Elliott Trudeau Intl

12h 47m

1 stop

SEA10:34 pmSeattle/Tacoma Intl

$486

Delta

Jun 30

SEA8:40 amSeattle/Tacoma Intl

12h 15m

1 stop

YUL11:55 pmMontreal Pierre Elliott Trudeau Intl

Aug 27

YUL12:47 pmMontreal Pierre Elliott Trudeau Intl

12h 18m

1 stop

SEA10:05 pmSeattle/Tacoma Intl

$488

Delta

Jun 29

SEA8:40 amSeattle/Tacoma Intl

12h 18m

1 stop

YYZ11:58 pmToronto Pearson Intl

Jul 2

YYZ7:24 pmToronto Pearson Intl

7h 35m

1 stop

SEA11:59 pmSeattle/Tacoma Intl

$496

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Quickest round-trip

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Sun 9/13

7:35 pm-5:45 am

1 stop7h 10m

Toronto Pearson Intl

Thu 9/17

1:30 pm-6:45 pm

1 stop8h 15m

$342

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Fri 9/11

7:35 pm-5:45 am

1 stop7h 10m

Toronto Pearson Intl

Sun 9/13

1:30 pm-6:45 pm

1 stop8h 15m

$346

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Thu 10/15

7:35 pm-5:45 am

1 stop7h 10m

Toronto Pearson Intl

Tue 10/20

1:30 pm-6:45 pm

1 stop8h 15m

$348

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Fri 10/16

7:35 pm-5:45 am

1 stop7h 10m

Toronto Pearson Intl

Tue 10/20

1:30 pm-6:45 pm

1 stop8h 15m

$349

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Tue 10/13

7:35 pm-5:45 am

1 stop7h 10m

Toronto Pearson Intl

Tue 10/20

1:30 pm-6:45 pm

1 stop8h 15m

$356

SeattleMontreal

SEA - YUL

SEAYUL

Seattle/Tacoma Intl

Thu 8/13

5:50 am-8:35 pm

2 stops11h 45m

Montreal Pierre Elliott Trudeau Intl

Wed 8/19

2:15 pm-10:42 pm

2 stops11h 27m

$401

SeattleMontreal

SEA - YUL

SEAYUL

Seattle/Tacoma Intl

Thu 8/13

10:30 am-12:25 am

2 stops10h 55m

Montreal Pierre Elliott Trudeau Intl

Wed 8/19

5:30 pm-10:42 pm

1 stop8h 12m

$409

SeattleTimmins

SEA - YTS

SEAYTS

Seattle/Tacoma Intl

Sat 10/31

7:45 am-10:28 pm

1 stop11h 43m

Timmins

Wed 11/4

5:15 am-2:37 pm

2 stops12h 22m

$627

SeattleTimmins

SEA - YTS

SEAYTS

Seattle/Tacoma Intl

Sat 10/31

8:40 am-10:33 am

2 stops22h 53m

Timmins

Wed 11/4

5:15 am-2:37 pm

2 stops12h 22m

$632

SeattleTimmins

SEA - YTS

SEAYTS

Seattle/Tacoma Intl

Sat 10/31

7:45 am-10:28 pm

1 stop11h 43m

Timmins

Wed 11/4

10:10 am-8:54 pm

1 stop13h 44m

$646

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 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 November is, on average, the cheapest month to fly to Region of Ontario from Seattle, with most prices found around $88. If you aren’t able to travel during the month of November, then book flights to Region of Ontario from Seattle during March instead. Flights to Region of Ontario in March, while not as cheap as those in November, still average around $93.

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 $510. 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 Sunday will generally be more expensive and average around $756. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

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 from Seattle to 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 $393 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 $291 on momondo.

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

There are 4 cabin classes available to choose from on Seattle to Region of 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 23% 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	$410
Fastest flight time	4h 39m
Direct flights	Tue, Wed, Thu, Fri, Sat and Sun
Airports in Region of Ontario	125 airports

The best one-way flight to Region of Ontario from Seattle in the past 72 hours is $410. The best round-trip flight deal from Seattle to Region of Ontario found on momondo in the last 72 hours is $566.

The fastest flight from Seattle to Region of Ontario takes 4h 39m

Direct flights go from Seattle to Region of Ontario on Tuesday, Wednesday, Thursday, Friday, Saturday and Sunday. The only airline offering direct flights is Alaska Airlines.

There are 125 airports in Region of Ontario. From Seattle there are direct flights to Toronto Pearson Intl (YYZ).

Search flight deals

Frequently asked questions about flying from Seattle to Ontario

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 5 as of June 2026.
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 Airbus A220-300, representing 58.56% of all bookings. The subsequent popular models are Boeing 737 MAX 8 at 7.43%, Boeing 737-900 Passenger/BBJ3 (winglets) at 5.63%, and Boeing 777-300ER at 3.60%.

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 $132	Free Cancellation	Rating 7.1 11,221 reviews	Search Air Canada flights
Delta	PriceFrom $142	Free Cancellation	Rating 7.8 8,419 reviews	Search Delta flights
WestJet	PriceFrom $226	Free Cancellation	Rating 7.2 3,375 reviews	Search WestJet flights
Alaska Airlines	PriceFrom $250	Free Cancellation	Rating 7.9 12,541 reviews	Search Alaska Airlines flights
United Airlines	PriceFrom $277	Free Cancellation	Rating 7.4 9,860 reviews	Search United 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

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Popular cities in Ontario

Flights to Torontofrom $172

Flights to Vancouverfrom $124

Flights to Montrealfrom $220

Flights to Calgaryfrom $216

Flights to Ottawafrom $234

Flights to Halifaxfrom $262

Flights to Winnipegfrom $306

Flights to Québec Cityfrom $328

Flights to Saskatoonfrom $299

Flights to Kelownafrom $236

Flights to St. John'sfrom $427

Flights to Reginafrom $366

Cheap flights from Seattle to Ontario from $160

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 11/16. 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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WestJet flights from Seattle to Region of Ontario

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

Delta flights from Seattle to Region of Ontario

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

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

See travel insights to Ontario from

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

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 Seattle/Tacoma Intl to Ontario flight route?

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

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

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

What is the cheapest airline that flies 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?

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

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

Frequently asked questions about flying from Seattle to 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?

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

Seattle flight routes

According to popular flight searches on momondo this year

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