How long is the flight from Region of Ontario to Seattle?

Departing from Region of Ontario to Seattle will take you 7h 40m. The distance from Region of Ontario to Seattle is about 3306 km. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.

What are the cheapest airlines to fly from Region of Ontario to Seattle one-way?

For one-way options, check prices for WestJet. According to our data, you can fly for as low as C$ 125. Users have also found prices from C$ 156 and C$ 174 on Air Canada and Alaska Airlines, respectively.

In terms of precipitation, rainfall in Seattle ranges from 18.0 - 168.0 mm per month. November is typically the wettest month, when rainfall can reach 168.0 mm. July is typically the driest time to visit Seattle when rainfall is around 18.0 mm.

If weather is an important factor for your trip to Seattle, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 19.0 C. Travellers hoping to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 5.0 C).

What are the most popular routes from Region of Ontario to Seattle?

The most popular route from Region of Ontario to Seattle is Toronto Pearson Intl - Seattle/Tacoma Intl. You may also consider Hamilton - Seattle/Tacoma Intl or Toronto Island - Seattle/Tacoma Intl.

What are the cheapest flights from Region of Ontario to Seattle?

Looking at all options, your cheapest flight can be booked for C$ 348. While the most popular route (Toronto Pearson Intl - Seattle/Tacoma Intl) can be booked for C$ 567 on average, our data indicates C$ 719 when flying from Region of Ontario to Seattle.

What are the most reliable airlines from Region of Ontario to Seattle?

No one likes to see their flight delayed. When booking a flight from Region of Ontario to Seattle consider choosing Alaska Airlines (83%), Brussels Airlines (38%) or Air Canada (33%) as they are the most reliable in getting you off to your destination on time.

What are the most popular airlines that fly from Region of Ontario to Seattle?

The most popular airlines flying from Region of Ontario to Seattle are WestJet, Alaska Airlines and Air Canada. Something to consider prior to booking your flight.

What airport do you fly into for flights to Seattle from Ontario?

Located just 18.4 km from the city centre, Seattle/Tacoma Intl (SEA) is the airport most travelers will use when flying to Seattle from Ontario.

Can I find deals for flights from Ontario to Seattle that include hotel bookings?

Yes. In addition to deals on Ontario to Seattle flights, Cheapflights offers vacation packages that include both flights and hotel.

How can I find direct flights from Ontario to Seattle?

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Seattle.

Can I find deals for business class flights from Ontario to Seattle?

Yes. Cheapflights offers flight deals from Ontario to Seattle by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

C$ 300+ Cheap Flights from Ontario to Seattle

Cheap flight deals from Ontario to Seattle

Enter your travel dates to find the best prices.

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Best

Direct

Last-minute

One-way

Cheapest flights from Ontario to Seattle
Explore the most affordable flight options available from Ontario to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 8 October 2026.

Fri 23/1012:00 p.m. -

1 stop9h 45m

Sun 1/112:30 p.m. -

2 stops12h 15m

Deal found 5/10C$ 491

Fri 23/1012:00 p.m. -

1 stop9h 45m

Thu 29/103:30 p.m. -

2 stops12h 15m

Deal found 7/10C$ 493

Thu 22/101:30 p.m. -

1 stop8h 15m

Wed 28/103:30 p.m. -

2 stops12h 15m

Deal found 7/10C$ 496

Thu 19/117:30 a.m. -

1 stop9h 10m

Thu 26/112:30 p.m. -

2 stops12h 15m

Deal found 5/10C$ 497

Wed 21/101:30 p.m. -

1 stop8h 15m

Sun 25/103:30 p.m. -

2 stops12h 15m

Deal found 7/10C$ 504

Fri 23/101:30 p.m. -

1 stop8h 15m

Wed 28/103:30 p.m. -

2 stops12h 15m

Deal found 7/10C$ 513

Tue 20/101:30 p.m. -

1 stop8h 15m

Sat 24/107:35 p.m. -

1 stop8h 20m

Deal found 6/10C$ 520

Sun 22/117:30 a.m. -

1 stop9h 10m

Sun 29/112:30 p.m. -

1 stop28h 40m

Deal found 7/10C$ 521

Fri 4/127:30 a.m. -

1 stop9h 10m

Thu 10/122:30 p.m. -

1 stop22h 25m

Deal found 5/10C$ 524

Wed 2/126:40 a.m. -

1 stop10h 00m

Wed 13/12:30 p.m. -

1 stop12h 05m

Deal found 6/10C$ 552

Wed 2/126:40 a.m. -

1 stop10h 00m

Wed 20/12:30 p.m. -

1 stop12h 05m

Deal found 5/10C$ 554

Sun 22/116:10 a.m. -

1 stop10h 30m

Sun 29/112:30 p.m. -

1 stop21h 00m

Deal found 5/10C$ 554

Best flights from Ontario to Seattle
Discover carefully curated flight deals from Ontario to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated 8 October 2026.

Wed 4/116:00 a.m. -

1 stop7h 40m

Wed 9/1210:40 p.m. -

1 stop9h 30m

Deal found 3/10C$ 567

Sun 22/117:30 a.m. -

1 stop9h 10m

Sun 29/112:30 p.m. -

2 stops20h 35m

Deal found 7/10C$ 639

Tue 2/24:36 p.m. -

1 stop9h 09m

Mon 8/22:20 p.m. -

2 stops19h 51m

Deal found 4/10C$ 661

Thu 19/117:00 p.m. -

1 stop21h 40m

Thu 26/112:30 p.m. -

1 stop22h 15m

Deal found 5/10C$ 730

Wed 18/1111:20 a.m. -

2 stops13h 37m

Wed 25/117:05 p.m. -

2 stops12h 06m

Deal found 4/10C$ 873

Sat 5/127:35 a.m. -

1 stop10h 03m

Thu 10/129:50 a.m. -

1 stop10h 17m

Deal found 5/10C$ 587

Fri 27/116:00 a.m. -

1 stop8h 09m

Tue 1/128:30 a.m. -

1 stop12h 28m

Deal found 5/10C$ 588

Tue 9/36:15 a.m. -

1 stop8h 35m

Mon 15/310:40 p.m. -

1 stop12h 38m

Deal found 3/10C$ 662

Wed 21/108:40 p.m. -

1 stop16h 00m

Thu 22/107:35 p.m. -

1 stop21h 15m

Deal found 5/10C$ 693

Tue 2/39:45 a.m. -

3 stops16h 49m

Mon 8/37:32 p.m. -

2 stops15h 46m

Deal found 3/10C$ 662

Thu 12/115:25 p.m. -

1 stop9h 32m

Mon 16/1111:15 p.m. -

1 stop9h 04m

Deal found 6/10C$ 608

Tue 2/22:00 p.m. -

1 stop10h 02m

Sat 6/27:00 a.m. -

2 stops11h 23m

Deal found 3/10C$ 662

Mon 7/1212:18 p.m. -

1 stop13h 51m

Thu 10/129:50 a.m. -

1 stop10h 17m

Deal found 5/10C$ 608

Tue 20/106:10 a.m. -

1 stop15h 35m

Thu 22/107:35 p.m. -

1 stop6h 45m

Deal found 6/10C$ 755

Fri 23/106:10 p.m. -

1 stop27h 35m

Tue 27/1012:14 p.m. -

3 stops24h 11m

Deal found 6/10C$ 843

Mon 16/112:20 p.m. -

1 stop10h 38m

Mon 23/111:50 p.m. -

1 stop6h 21m

Deal found 7/10C$ 609

Thu 12/116:15 a.m. -

2 stops17h 41m

Sun 22/117:35 p.m. -

2 stops15h 34m

Deal found 6/10C$ 686

Mon 9/113:25 p.m. -

1 stop8h 34m

Mon 16/117:45 a.m. -

1 stop11h 07m

Deal found 5/10C$ 928

Thu 14/17:00 p.m. -

1 stop16h 52m

Thu 28/17:10 a.m. -

2 stops29h 35m

Deal found 6/10C$ 847

Fri 13/116:30 a.m. -

1 stop7h 12m

Thu 3/1211:15 p.m. -

1 stop6h 40m

Deal found 3/10C$ 609

Fri 13/113:10 p.m. -

1 stop9h 29m

Sun 22/117:04 p.m. -

2 stops21h 23m

Deal found 7/10C$ 686

Fri 23/106:10 p.m. -

1 stop27h 35m

Wed 28/103:30 p.m. -

1 stop20h 55m

Deal found 7/10C$ 850

Sat 13/27:00 p.m. -

1 stop16h 00m

Sun 28/22:30 p.m. -

1 stop22h 15m

Deal found 6/10C$ 870

Thu 19/113:10 p.m. -

1 stop9h 29m

Mon 23/1110:56 p.m. -

1 stop12h 13m

Deal found 6/10C$ 686

Fri 30/1012:49 p.m. -

2 stops12h 11m

Mon 16/1111:15 p.m. -

1 stop6h 40m

Deal found 7/10C$ 629

Sat 24/106:05 a.m. -

2 stops11h 17m

Sat 31/103:20 p.m. -

1 stop21h 05m

Deal found 6/10C$ 876

Sun 18/106:10 p.m. -

1 stop18h 30m

Thu 22/107:35 p.m. -

1 stop18h 40m

Deal found 4/10C$ 879

Sun 20/123:20 p.m. -

1 stop8h 39m

Wed 30/127:05 p.m. -

2 stops16h 37m

Deal found 4/10C$ 1,069

Thu 29/109:45 a.m. -

1 stop14h 11m

Sun 8/118:35 p.m. -

2 stops21h 41m

Deal found 6/10C$ 686

Thu 19/119:45 a.m. -

1 stop8h 05m

Sat 21/117:35 p.m. -

2 stops10h 20m

Deal found 7/10C$ 629

Find flight deals from Ontario to Seattle

Round-trip from	C$ 470
One-way from	C$ 300
Popular in	June
Cheapest in	February
Average price	C$ 608
Good round-trip deal	C$ 669 or less
Good one-way deal	C$ 415 or less

WestJet
13/1-21/1
3 total stops
21h 25m total
Ontario to Seattle

Search Deals

WestJet
17/11-31/12
2 total stops
9h 40m total
Ontario to Seattle

Search Deals

Highest demand for flights based on searches. 8% potential increase in price (C$ 72 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 2% potential price decrease (C$ 17 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in October 2026

Search Deals

Price to beat on a round-trip flight from Ontario to Seattle/Tacoma Intl.

Search Deals

Price to beat on a one-way flight from Ontario to Seattle/Tacoma Intl.

Search Deals

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

HamiltonSeattle

YHM Hamilton - SEA Seattle/Tacoma Intl

YHMSEA

Hamilton

Thu 19/11

3:25 p.m.-1:40 p.m.

1 stop25h 15m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 312

TorontoSeattle

YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl

YYZSEA

Toronto Pearson Intl

Tue 10/11

5:25 p.m.-11:57 p.m.

1 stop9h 32m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 325

TorontoSeattle

YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl

YYZSEA

Toronto Pearson Intl

Mon 8/2

12:10 p.m.-7:23 p.m.

1 stop10h 13m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 346

TorontoSeattle

YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl

YYZSEA

Toronto Pearson Intl

Mon 9/11

9:45 a.m.-6:37 p.m.

1 stop11h 52m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 346

OttawaSeattle

YOW Ottawa - SEA Seattle/Tacoma Intl

YOWSEA

Ottawa

Fri 6/11

10:05 a.m.-8:59 p.m.

1 stop13h 54m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 367

OttawaSeattle

YOW Ottawa - SEA Seattle/Tacoma Intl

YOWSEA

Ottawa

Wed 18/11

6:10 a.m.-1:40 p.m.

1 stop10h 30m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 369

OttawaSeattle

YOW Ottawa - SEA Seattle/Tacoma Intl

YOWSEA

Ottawa

Sat 5/12

7:50 a.m.-6:22 p.m.

2 stops13h 32m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 377

OttawaSeattle

YOW Ottawa - SEA Seattle/Tacoma Intl

YOWSEA

Ottawa

Sat 5/12

6:15 a.m.-9:21 p.m.

2 stops18h 06m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 384

OttawaSeattle

YOW Ottawa - SEA Seattle/Tacoma Intl

YOWSEA

Ottawa

Tue 17/11

6:15 a.m.-8:47 p.m.

2 stops17h 32m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 384

Quickest round-trip

TorontoSeattle

YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl

YYZSEA

Toronto Pearson Intl

Tue 10/11

5:15 p.m.-7:45 p.m.

Nonstop5h 30m

Seattle/Tacoma Intl

Wed 31/12

12:00 a.m.-3:00 a.m.

Nonstop0h 00m

C$ 389

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/10

Showing 1-10 of 60 resultsSorted by cheapest first

...

Best time to book a flight from Ontario to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Ontario with our price prediction graph.

YYZ-SEA

YHM-SEA

YOW-SEA

YKF-SEA

YQT-SEA

Estimated round-trip price

Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Ontario to Seattle

CAON-SEA

YYZ-SEA

YHM-SEA

YOW-SEA

YKF-SEA

What is the cheapest month to book a flight from Region of Ontario to Seattle?

Currently, February is the cheapest month in which you can book a flight from Region of Ontario to Seattle (average of C$ 355). Flying from Region of Ontario to Seattle in July is currently the most expensive (average of C$ 668). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from ON to SEA?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Region of Ontario to Seattle as you normally would.

Weekly flight availability from Region of Ontario to Seattle

The most flights from CAON to SEA are scheduled on a Tuesday (5 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (1 on average).

How much does it cost to fly round-trip from Region of Ontario to Seattle?

Airfare is below average for this route at the moment.

Region of Ontario to Seattle flights typically cost between C$ 497 and C$ 792 in January.
The cheapest round-trip price found within the last 5 days was C$ 470 on WestJet (13 Jan-21 Jan).

How far ahead should I book a flight from Region of Ontario to Seattle?

Booking 74 days in advance of your planned departure date is, on average, the best time to get cheap flights from Region of Ontario to Seattle. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

Related info for your journey

What airport do you fly into for flights to Seattle from Ontario?
Located just 18.4 km from the city centre, Seattle/Tacoma Intl (SEA) is the airport most travelers will use when flying to Seattle from Ontario.
How long is the flight from Region of Ontario to Seattle?
Departing from Region of Ontario to Seattle will take you 7h 40m. The distance from Region of Ontario to Seattle is about 3306 km. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.
What are the cheapest airlines to fly from Region of Ontario to Seattle one-way?
For one-way options, check prices for WestJet. According to our data, you can fly for as low as C$ 125. Users have also found prices from C$ 156 and C$ 174 on Air Canada and Alaska Airlines, respectively.
What are the most popular routes from Region of Ontario to Seattle?
The most popular route from Region of Ontario to Seattle is Toronto Pearson Intl - Seattle/Tacoma Intl. You may also consider Hamilton - Seattle/Tacoma Intl or Toronto Island - Seattle/Tacoma Intl.
What are the most reliable airlines from Region of Ontario to Seattle?
No one likes to see their flight delayed. When booking a flight from Region of Ontario to Seattle consider choosing Alaska Airlines (83%), Brussels Airlines (38%) or Air Canada (33%) as they are the most reliable in getting you off to your destination on time.
What are the cheapest flights from Region of Ontario to Seattle?
Looking at all options, your cheapest flight can be booked for C$ 348. While the most popular route (Toronto Pearson Intl - Seattle/Tacoma Intl) can be booked for C$ 567 on average, our data indicates C$ 719 when flying from Region of Ontario to Seattle.
Can I find deals for flights from Ontario to Seattle that include hotel bookings?
Yes. In addition to deals on Ontario to Seattle flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Ontario to Seattle?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Seattle.
Can I find deals for business class flights from Ontario to Seattle?
Yes. Cheapflights offers flight deals from Ontario to Seattle by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.
What is the cheapest month to book a flight from Region of Ontario to Seattle?
Currently, February is the cheapest month in which you can book a flight from Region of Ontario to Seattle (average of C$ 355). Flying from Region of Ontario to Seattle in July is currently the most expensive (average of C$ 668). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

SeaTac

Kent

Mukilteo

Renton

Lynnwood

Cashmere

Ellensburg

Leavenworth

Tukwila

Tacoma

Marysville

Federal Way

Kirkland

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Alternative routes for Ontario to Seattle

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Top 5 airlines flying from Ontario to Seattle

Airline	Cheapest	Average	Flexibility	On-time
Delta	CheapestC$ 230	AverageC$ 859	FlexibilityNo cancel fee	On-timeN/A	Search Delta flights
Air Canada	CheapestC$ 257	AverageC$ 666	FlexibilityNo cancel fee	On-time67%	Search Air Canada flights
United Airlines	CheapestC$ 259	AverageC$ 780	FlexibilityNo cancel fee	On-time69%	Search United Airlines flights
Alaska Airlines	CheapestC$ 276	AverageC$ 478	FlexibilityNo cancel fee	On-time75%	Search Alaska Airlines flights
WestJet	CheapestC$ 295	AverageC$ 542	FlexibilityNo cancel fee	On-time60%	Search WestJet flights

Fly with Cheapflights

How does Cheapflights help users find flights from Ontario to Seattle?

900+ travel sites are searched through when a user searches for a flight using Cheapflights. From the search interface, users can use filters to choose airlines, airports, flight times, cabin classes and more to their preference. Book your flight to Seattle from Ontario today with Cheapflights!

Why should you use Cheapflights to find cheap flight tickets from Ontario to Seattle?

Millions of users choose and trust Cheapflights to book the best flight deals from Ontario to Seattle for free. We help you search and compare prices from hundreds of airlines for the right flight just for you.

Can Cheapflights find flights from Ontario to Seattle with no change fees?

Need flexible booking options for your flight to Seattle from Ontario? Don’t worry, Cheapflights have you covered. Use our search filter to only show flights with no change fees.

Can Cheapflights notify me if prices for flights from Ontario to Seattle become cheaper?

Of course! You can now track prices for flights from Ontario to Seattle and get an alert from Cheapflights when they change. Have a valid email address ready and click the bell icon next to the flight deals above to set up your price alerts.

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Cheap flights from Ontario to Seattle from C$ 300

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 17/11. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap flight deals from Ontario to Seattle

Cheapest flights from Ontario to SeattleExplore the most affordable flight options available from Ontario to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 8 October 2026.

Explore the most affordable flight options available from Ontario to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 8 October 2026.

Best flights from Ontario to SeattleDiscover carefully curated flight deals from Ontario to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated 8 October 2026.

Discover carefully curated flight deals from Ontario to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated 8 October 2026.

Direct flights from Ontario to SeattleExplore direct flight options from Ontario to Seattle based on user searches, and compare prices and availability for your desired travel dates. Data last updated 8 October 2026.

Explore direct flight options from Ontario to Seattle based on user searches, and compare prices and availability for your desired travel dates. Data last updated 8 October 2026.

Last-minute flights from Ontario to SeattleDiscover last-minute flight deals from Ontario to Seattle. Data last updated 8 October 2026 and is based on user searches.

Discover last-minute flight deals from Ontario to Seattle. Data last updated 8 October 2026 and is based on user searches.

One-way flights from Ontario to SeattleSearch for one-way flight options from Ontario to Seattle. Find affordable one-way fares based on user searches. Data last updated 8 October 2026.

Search for one-way flight options from Ontario to Seattle. Find affordable one-way fares based on user searches. Data last updated 8 October 2026.

Find flight deals from Ontario to Seattle

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Cheapflights Fare Finder

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

Best time to book a flight from Ontario to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Ontario with our price prediction graph.

Cheapflights Insights

What is the cheapest month to book a flight from Region of Ontario to Seattle?

What is the cheapest time of day to fly from ON to SEA?

Find hourly flight availability from Ontario to Seattle. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 8 October 2026.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Region of Ontario to Seattle as you normally would.

Weekly flight availability from Region of Ontario to Seattle

Explore weekly flight availability from Ontario to Seattle. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated 8 October 2026.

The most flights from CAON to SEA are scheduled on a Tuesday (5 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (1 on average).

How much does it cost to fly round-trip from Region of Ontario to Seattle?

Airfare is below average for this route at the moment.

Region of Ontario to Seattle flights typically cost between C$ 497 and C$ 792 in January.The cheapest round-trip price found within the last 5 days was C$ 470 on WestJet (13 Jan-21 Jan).

How far ahead should I book a flight from Region of Ontario to Seattle?

Booking 74 days in advance of your planned departure date is, on average, the best time to get cheap flights from Region of Ontario to Seattle. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

Related info for your journey

What airport do you fly into for flights to Seattle from Ontario?

How long is the flight from Region of Ontario to Seattle?

What are the cheapest airlines to fly from Region of Ontario to Seattle one-way?

What are the most popular routes from Region of Ontario to Seattle?

What are the most reliable airlines from Region of Ontario to Seattle?

What are the cheapest flights from Region of Ontario to Seattle?

Can I find deals for flights from Ontario to Seattle that include hotel bookings?

How can I find direct flights from Ontario to Seattle?

Can I find deals for business class flights from Ontario to Seattle?

What is the cheapest month to book a flight from Region of Ontario to Seattle?

Travelling to a place near Seattle?

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Ontario to Seattle

See prices for flight routes from nearby airports that may be better suited for you.

Complete your trip

Complete your trip to Seattle by adding a car rental and/or hotel reservation to your travel itinerary.

Direct flights to Washington

Book a non-stop flight to one of these other cities located in Washington.

Search flights from Ontario to Seattle by cabin class

Find flights from Ontario to Seattle, based on your preferred cabin class, be it economy, premium economy, business, or first class.

Ontario and Seattle flights

Browse other Ontario and Seattle flight options. Last updated on 8 October 2026.

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Ontario to Seattle flights

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Cheapest flights from Ontario to Seattle
Explore the most affordable flight options available from Ontario to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 8 October 2026.

Best flights from Ontario to Seattle
Discover carefully curated flight deals from Ontario to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated 8 October 2026.

Direct flights from Ontario to Seattle
Explore direct flight options from Ontario to Seattle based on user searches, and compare prices and availability for your desired travel dates. Data last updated 8 October 2026.

Last-minute flights from Ontario to Seattle
Discover last-minute flight deals from Ontario to Seattle. Data last updated 8 October 2026 and is based on user searches.

One-way flights from Ontario to Seattle
Search for one-way flight options from Ontario to Seattle. Find affordable one-way fares based on user searches. Data last updated 8 October 2026.

Region of Ontario to Seattle flights typically cost between C$ 497 and C$ 792 in January.
The cheapest round-trip price found within the last 5 days was C$ 470 on WestJet (13 Jan-21 Jan).