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

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

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 49% 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.

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

As of August 2026, there are 3 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 26 per week as of August 2026. The most frequent departure day is Mon, with 15% of weekly flights leaving 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 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 August 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$ 204 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. - 5:35 a.m.-

7h 00m

12:25 p.m. - 6:45 p.m.-

9h 20m

C$ 488WestJet

Wed, 23 Sep - Thu, 24 Sep

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

7h 00m

12:25 p.m. - 6:45 p.m.-

9h 20m

C$ 502WestJet

Wed, 9 Sep - Sat, 19 Sep

7:35 p.m. - 7:05 a.m.-

8h 30m

5:00 p.m. - 10:42 p.m.-

8h 42m

C$ 502Multiple Airlines

Thu, 27 Aug - Wed, 2 Sep

7:35 p.m. - 7:05 a.m.-

8h 30m

9:00 a.m. - 6:32 p.m.-

12h 32m

C$ 503Multiple Airlines

Thu, 27 Aug - Wed, 2 Sep

7:20 p.m. - 7:10 a.m.-

8h 50m

9:00 a.m. - 6:32 p.m.-

12h 32m

C$ 510Air Canada

Thu, 27 Aug - Wed, 2 Sep

7:35 p.m. - 7:05 a.m.-

8h 30m

5:00 p.m. - 10:42 p.m.-

8h 42m

C$ 512Multiple Airlines

Thu, 27 Aug - Wed, 2 Sep

7:35 p.m. - 7:05 a.m.-

8h 30m

6:45 a.m. - 6:45 p.m.-

15h 00m

C$ 519WestJet

Mon, 21 Sep - Thu, 24 Sep

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

8h 45m

12:30 a.m. - 10:05 a.m.-

12h 35m

C$ 566Air Canada

Tue, 15 Sep - Mon, 21 Sep

8:18 a.m. - 4:05 p.m.-

4h 47mdirect

5:15 p.m. - 7:44 p.m.-

5h 29mdirect

C$ 614Alaska Airlines

Wed, 4 Nov - Wed, 11 Nov

7:52 a.m. - 3:45 p.m.-

4h 53mdirect

4:55 p.m. - 7:13 p.m.-

5h 18mdirect

C$ 624Alaska Airlines

Sat, 19 Sep - Tue, 22 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

23 Sep

SEA7:35 p.m.Seattle/Tacoma Intl

7h 00m

1 stop

YOW5:35 a.m.Ottawa

24 Sep

YOW12:25 p.m.Ottawa

9h 20m

2 stops

SEA6:45 p.m.Seattle/Tacoma Intl

C$ 488

WestJet

9 Sep

SEA7:35 p.m.Seattle/Tacoma Intl

7h 00m

1 stop

YOW5:35 a.m.Ottawa

19 Sep

YOW12:25 p.m.Ottawa

9h 20m

2 stops

SEA6:45 p.m.Seattle/Tacoma Intl

C$ 502

WestJet

21 Sep

SEA7:35 p.m.Seattle/Tacoma Intl

8h 30m

1 stop

YUL7:05 a.m.Montreal Pierre Elliott Trudeau Intl

24 Sep

YUL6:45 a.m.Montreal Pierre Elliott Trudeau Intl

15h 00m

2 stops

SEA6:45 p.m.Seattle/Tacoma Intl

C$ 519

Air Canada flights from Seattle to Region of Ontario

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

Air Canada

27 Aug

SEA7:20 p.m.Seattle/Tacoma Intl

8h 50m

2 stops

YUL7:10 a.m.Montreal Pierre Elliott Trudeau Intl

2 Sep

YUL9:00 a.m.Montreal Pierre Elliott Trudeau Intl

12h 32m

2 stops

SEA6:32 p.m.Seattle/Tacoma Intl

C$ 510

Air Canada

27 Aug

SEA7:20 p.m.Seattle/Tacoma Intl

8h 50m

2 stops

YUL7:10 a.m.Montreal Pierre Elliott Trudeau Intl

2 Sep

YUL9:00 a.m.Montreal Pierre Elliott Trudeau Intl

12h 32m

2 stops

SEA6:32 p.m.Seattle/Tacoma Intl

C$ 551

Air Canada

5 Nov

SEA10:10 a.m.Seattle/Tacoma Intl

7h 23m

1 stop

YUL8:33 p.m.Montreal Pierre Elliott Trudeau Intl

12 Nov

YUL8:45 a.m.Montreal Pierre Elliott Trudeau Intl

8h 52m

1 stop

SEA2:37 p.m.Seattle/Tacoma Intl

C$ 568

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattleOttawa

SEA - YOW

SEAYOW

Seattle/Tacoma Intl

Wed 23/9

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

1 stop7h 00m

Ottawa

Thu 24/9

12:25 p.m.-6:45 p.m.

2 stops9h 20m

C$ 488

SeattleOttawa

SEA - YOW

SEAYOW

Seattle/Tacoma Intl

Wed 9/9

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

1 stop7h 00m

Ottawa

Sat 19/9

12:25 p.m.-6:45 p.m.

2 stops9h 20m

C$ 502

SeattleMontreal

SEA - YUL

SEAYUL

Seattle/Tacoma Intl

Thu 27/8

7:35 p.m.-7:05 a.m.

1 stop8h 30m

Montreal Pierre Elliott Trudeau Intl

Wed 2/9

5:00 p.m.-10:42 p.m.

1 stop8h 42m

C$ 502

SeattleMontreal

SEA - YUL

SEAYUL

Seattle/Tacoma Intl

Thu 27/8

7:35 p.m.-7:05 a.m.

1 stop8h 30m

Montreal Pierre Elliott Trudeau Intl

Wed 2/9

9:00 a.m.-6:32 p.m.

2 stops12h 32m

C$ 503

SeattleMontreal

SEA - YUL

SEAYUL

Seattle/Tacoma Intl

Thu 27/8

7:20 p.m.-7:10 a.m.

2 stops8h 50m

Montreal Pierre Elliott Trudeau Intl

Wed 2/9

9:00 a.m.-6:32 p.m.

2 stops12h 32m

C$ 510

SeattleMontreal

SEA - YUL

SEAYUL

Seattle/Tacoma Intl

Thu 27/8

7:35 p.m.-7:05 a.m.

1 stop8h 30m

Montreal Pierre Elliott Trudeau Intl

Wed 2/9

5:00 p.m.-10:42 p.m.

1 stop8h 42m

C$ 512

SeattleMontreal

SEA - YUL

SEAYUL

Seattle/Tacoma Intl

Mon 21/9

7:35 p.m.-7:05 a.m.

1 stop8h 30m

Montreal Pierre Elliott Trudeau Intl

Thu 24/9

6:45 a.m.-6:45 p.m.

2 stops15h 00m

C$ 519

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Tue 15/9

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

2 stops8h 45m

Toronto Pearson Intl

Mon 21/9

12:30 a.m.-10:05 a.m.

2 stops12h 35m

C$ 566

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Wed 4/11

8:18 a.m.-4:05 p.m.

Nonstop4h 47m

Toronto Pearson Intl

Wed 11/11

5:15 p.m.-7:44 p.m.

Nonstop5h 29m

C$ 614

Quickest round-trip

SeattleToronto

SEA - YYZ

SEAYYZ

Seattle/Tacoma Intl

Sat 19/9

7:52 a.m.-3:45 p.m.

Nonstop4h 53m

Toronto Pearson Intl

Tue 22/9

4:55 p.m.-7:13 p.m.

Nonstop5h 18m

C$ 624

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, January 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$ 385. If you are unable to visit Region of Ontario during the month of January, then departing from Seattle during the month February is also very affordable. Most momondo users find prices during this month for around C$ 422.

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$ 758. The most expensive day to fly to Region of Ontario is Monday, with ticket prices averaging around C$ 990.

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$ 560 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$ 447 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?

No. A direct flight is the cheapest option for a flight between Seattle to Region of Ontario.

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$ 442
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$ 442. The best round-trip flight deal from Seattle to Region of Ontario found on momondo in the last 72 hours is C$ 909.

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 August 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 (57.76% of total bookings). The next most popular plane models are Boeing 737-900 Passenger/BBJ3 (winglets) (5.61%), Boeing 777-300ER (5.28%), and Airbus A350-900 (4.29%).

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 C$ 263	Free Cancellation	Rating 7.1 11,429 reviews	Search Air Canada flights
Alaska Airlines	PriceFrom C$ 286	Free Cancellation	Rating 7.9 12,767 reviews	Search Alaska Airlines flights
WestJet	PriceFrom C$ 290	Free Cancellation	Rating 7.2 3,426 reviews	Search WestJet 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$ 118

Flights to Vancouverfrom C$ 103

Flights to Montrealfrom C$ 233

Flights to Calgaryfrom C$ 117

Flights to Halifaxfrom C$ 179

Flights to Winnipegfrom C$ 128

Flights to Ottawafrom C$ 194

Flights to Kelownafrom C$ 136

Flights to Saskatoonfrom C$ 156

Flights to St. John'sfrom C$ 250

Flights to Reginafrom C$ 216

Flights to Vancouverfrom C$ 104

Cheap flights from Seattle to Ontario from C$ 204

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 1/10. 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

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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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

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

Region of Ontario flight routes

According to popular flight searches on momondo this year

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