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

WestJet, Alaska Airlines, and United Airlines 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 day?

As of June 2026, there are 4 flights per day flying from Seattle to Region of Ontario. The most common time of day flights depart is 8:00a.m., with 100% of flights taking off at noon.

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

The number of flights available between Seattle and Region of Ontario is 30 per week as of June 2026. The most frequent departure day is Wed, with 17% of weekly flights leaving on this day.

Which airlines fly to Region of Ontario?

Alaska Airlines, WestJet and Air Canada 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 54% of people opting to fly with this airline when travelling to Region of Ontario. Keep in mind that there are 3 different airlines that fly to Region of Ontario on a routine basis, so you have a few additional options to choose from.

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 updated daily.

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 3 as of June 2026.

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

The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Seattle/Tacoma Intl Airport to Ontario.

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

The travel and health documents required for your trip to Ontario can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Ontario. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

C$ 226 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 p.m. - 6:55 a.m.

SEA

YYZ

8h 20m

1 stop

1:30 p.m. - 6:45 p.m.

YYZ

SEA

8h 15m

1 stop

C$ 483WestJet

Sat, 19 Sep - Mon, 21 Sep

7:35 p.m. - 5:45 a.m.

SEA

YYZ

7h 10m

1 stop

1:30 p.m. - 6:45 p.m.

YYZ

SEA

8h 15m

1 stop

C$ 484WestJet

Sun, 13 Sep - Thu, 17 Sep

7:35 p.m. - 5:45 a.m.

SEA

YYZ

7h 10m

1 stop

1:30 p.m. - 6:45 p.m.

YYZ

SEA

8h 15m

1 stop

C$ 488WestJet

Fri, 11 Sep - Mon, 14 Sep

7:35 p.m. - 5:45 a.m.

SEA

YYZ

7h 10m

1 stop

1:30 p.m. - 6:45 p.m.

YYZ

SEA

8h 15m

1 stop

C$ 490WestJet

Fri, 11 Sep - Sun, 13 Sep

7:35 p.m. - 5:45 a.m.

SEA

YYZ

7h 10m

1 stop

1:30 p.m. - 6:45 p.m.

YYZ

SEA

8h 15m

1 stop

C$ 493WestJet

Thu, 15 Oct - Tue, 20 Oct

7:35 p.m. - 5:45 a.m.

SEA

YYZ

7h 10m

1 stop

1:30 p.m. - 6:45 p.m.

YYZ

SEA

8h 15m

1 stop

C$ 494WestJet

Fri, 16 Oct - Tue, 20 Oct

5:50 a.m. - 8:35 p.m.

SEA

YUL

11h 45m

2 stops

2:15 p.m. - 10:42 p.m.

YUL

SEA

11h 27m

2 stops

C$ 568Air Canada

Thu, 13 Aug - Wed, 19 Aug

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

SEA

YTZ

9h 00m

1 stop

1:40 p.m. - 9:38 p.m.

YTZ

SEA

10h 58m

1 stop

C$ 702Multiple Airlines

Wed, 16 Sep - Sat, 19 Sep

8:00 a.m. - 9:57 p.m.

SEA

YAM

10h 57m

1 stop

2:00 p.m. - 9:04 p.m.

YAM

SEA

10h 04m

1 stop

C$ 892Air Canada

Wed, 23 Sep - Sat, 26 Sep

3:00 p.m. - 1:22 p.m.

SEA

YAM

19h 22m

2 stops

2:00 p.m. - 9:04 p.m.

YAM

SEA

10h 04m

1 stop

C$ 899Air Canada

Wed, 23 Sep - Sat, 26 Sep

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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

19 Sep

SEA7:35 p.m.Seattle/Tacoma Intl

8h 20m

1 stop

YYZ6:55 a.m.Toronto Pearson Intl

21 Sep

YYZ1:30 p.m.Toronto Pearson Intl

8h 15m

1 stop

SEA6:45 p.m.Seattle/Tacoma Intl

C$ 483

WestJet

13 Sep

SEA7:35 p.m.Seattle/Tacoma Intl

7h 10m

1 stop

YYZ5:45 a.m.Toronto Pearson Intl

17 Sep

YYZ1:30 p.m.Toronto Pearson Intl

8h 15m

1 stop

SEA6:45 p.m.Seattle/Tacoma Intl

C$ 484

WestJet

11 Sep

SEA7:35 p.m.Seattle/Tacoma Intl

7h 10m

1 stop

YYZ5:45 a.m.Toronto Pearson Intl

13 Sep

YYZ1:30 p.m.Toronto Pearson Intl

8h 15m

1 stop

SEA6:45 p.m.Seattle/Tacoma Intl

C$ 490

Delta flights from Seattle to Region of Ontario

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

Delta

4 Jul

SEA8:40 a.m.Seattle/Tacoma Intl

12h 15m

1 stop

YUL11:55 p.m.Montreal Pierre Elliott Trudeau Intl

24 Aug

YUL6:00 a.m.Montreal Pierre Elliott Trudeau Intl

11h 34m

1 stop

SEA2:34 p.m.Seattle/Tacoma Intl

C$ 672

Delta

30 Jun

SEA9:45 a.m.Seattle/Tacoma Intl

10h 43m

1 stop

YUL11:28 p.m.Montreal Pierre Elliott Trudeau Intl

4 Jul

YUL12:47 p.m.Montreal Pierre Elliott Trudeau Intl

12h 47m

1 stop

SEA10:34 p.m.Seattle/Tacoma Intl

C$ 688

Delta

30 Jun

SEA8:40 a.m.Seattle/Tacoma Intl

12h 15m

1 stop

YUL11:55 p.m.Montreal Pierre Elliott Trudeau Intl

27 Aug

YUL12:47 p.m.Montreal Pierre Elliott Trudeau Intl

12h 18m

1 stop

SEA10:05 p.m.Seattle/Tacoma Intl

C$ 691

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Sat 19/9

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

1 stop8h 20m

Toronto Pearson Intl

Mon 21/9

1:30 p.m.-6:45 p.m.

1 stop8h 15m

C$ 483

Quickest round-trip

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Sun 13/9

7:35 p.m.-5:45 a.m.

1 stop7h 10m

Toronto Pearson Intl

Thu 17/9

1:30 p.m.-6:45 p.m.

1 stop8h 15m

C$ 484

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Fri 11/9

7:35 p.m.-5:45 a.m.

1 stop7h 10m

Toronto Pearson Intl

Mon 14/9

1:30 p.m.-6:45 p.m.

1 stop8h 15m

C$ 488

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Fri 11/9

7:35 p.m.-5:45 a.m.

1 stop7h 10m

Toronto Pearson Intl

Sun 13/9

1:30 p.m.-6:45 p.m.

1 stop8h 15m

C$ 490

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Thu 15/10

7:35 p.m.-5:45 a.m.

1 stop7h 10m

Toronto Pearson Intl

Tue 20/10

1:30 p.m.-6:45 p.m.

1 stop8h 15m

C$ 493

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Fri 16/10

7:35 p.m.-5:45 a.m.

1 stop7h 10m

Toronto Pearson Intl

Tue 20/10

1:30 p.m.-6:45 p.m.

1 stop8h 15m

C$ 494

SeattleMontreal

SEA - YUL

SEAYUL

Seattle/Tacoma Intl

Thu 13/8

5:50 a.m.-8:35 p.m.

2 stops11h 45m

Montreal Pierre Elliott Trudeau Intl

Wed 19/8

2:15 p.m.-10:42 p.m.

2 stops11h 27m

C$ 568

SeattleToronto

SEA - YTZ

SEAYTZ

Seattle/Tacoma Intl

Wed 16/9

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

1 stop9h 00m

Toronto Island

Sat 19/9

1:40 p.m.-9:38 p.m.

1 stop10h 58m

C$ 702

SeattleSault Ste Marie

SEA - YAM

SEAYAM

Seattle/Tacoma Intl

Wed 23/9

8:00 a.m.-9:57 p.m.

1 stop10h 57m

Sault Ste Marie

Sat 26/9

2:00 p.m.-9:04 p.m.

1 stop10h 04m

C$ 892

SeattleSault Ste Marie

SEA - YAM

SEAYAM

Seattle/Tacoma Intl

Wed 23/9

3:00 p.m.-1:22 p.m.

2 stops19h 22m

Sault Ste Marie

Sat 26/9

2:00 p.m.-9:04 p.m.

1 stop10h 04m

C$ 899

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?

In general, November is the cheapest month to fly from Seattle to Region of Ontario. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around C$ 125. If you are unable to visit Region of Ontario during the month of November, then departing from Seattle during the month March is also very affordable. Most momondo users find prices during this month for around C$ 132.

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

The cheapest day to depart from Seattle to Region of Ontario is on a Thursday. Travellers who choose to depart for Region of Ontario on a Thursday will often find tickets for as low as C$ 550. The most expensive day to fly to Region of Ontario is Monday, with ticket prices averaging around C$ 1,051.

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 C$ 557 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 C$ 412 on momondo.

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

There are 3 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 16% 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	C$ 447
Fastest flight time	4h 39m
Direct flights	Every day
Airports in Region of Ontario	125 airports

The best one-way flight to Region of Ontario from Seattle in the past 72 hours is C$ 447. The best round-trip flight deal from Seattle to Region of Ontario found on momondo in the last 72 hours is C$ 764.

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

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

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 updated daily.
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 3 as of June 2026.
How old do you have to be to fly from Seattle/Tacoma Intl Airport to Ontario?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Seattle/Tacoma Intl Airport to Ontario.
What documentation or ID do you need to fly to Ontario?
The travel and health documents required for your trip to Ontario can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Ontario. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular plane model from Seattle to Region of Ontario?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from Seattle to Region of Ontario is Airbus A220-300 (58.56% of total bookings). The next most popular plane models are Boeing 737 MAX 8 (7.43%), Boeing 737-900 Passenger/BBJ3 (winglets) (5.63%), and Boeing 777-300ER (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
WestJet	PriceFrom C$ 292	Free Cancellation	Rating 7.2 3,375 reviews	Search WestJet flights
Alaska Airlines	PriceFrom C$ 313	Free Cancellation	Rating 7.9 12,549 reviews	Search Alaska Airlines flights
Air Canada	PriceFrom C$ 374	Free Cancellation	Rating 7.1 11,226 reviews	Search Air Canada flights

Why use momondo?

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

It is quick and easy to find Seattle to Ontario flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to Ontario that suits you.

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 all potential Seattle to Ontario flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.

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

Yes. momondo can track prices for Seattle to Ontario flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.

An easier way to manage your Region of Ontario trip

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Popular Cities in Ontario

Flights to Torontofrom C$ 137

Flights to Vancouverfrom C$ 103

Flights to Montrealfrom C$ 197

Flights to Calgaryfrom C$ 127

Flights to Winnipegfrom C$ 146

Flights to Ottawafrom C$ 209

Flights to Halifaxfrom C$ 174

Flights to Kelownafrom C$ 117

Flights to Saskatoonfrom C$ 229

Flights to Reginafrom C$ 259

Flights to St. John'sfrom C$ 277

Flights to Québec Cityfrom C$ 320

Cheap flights from Seattle to Ontario from C$ 226

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 16/11. 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?

Which 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

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According to popular flight searches on momondo this year

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