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

The cheapest airlines for a one-way flight from Region of Ontario to State of Washington are WestJet ($139), Air Canada ($167), and Alaska Airlines ($175).

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

When searching for a good deal, it’s best to be prepared for potential fluctuations in price. We recommend booking at least 53 days in advance, which can save you up to 76% on flights from Region of Ontario to State of Washington compared to booking the week you need them. Waiting 53 days out may not be for everyone, so we have options available for flights within the next two weeks, with the lowest price starting at $399. For sooner than that we have options available in the next 3 days from $772.

What is the cheapest month to fly from Region of Ontario to State of Washington?

Due to multiple factors, expect to potentially pay more when booking in May. For low rates, February can be a great choice for travel to State of Washington. Flights to State of Washington from Region of Ontario in February are about $389 on average during February, but can be found for as low as $212.

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

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

How can I find direct flights from Ontario to Washington?

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

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

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

$139+ Flights from Ontario to Washington

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Cheap flight deals from Ontario to Washington

Most accurate provider	FlightHub 3 stars
Most trusted provider	FlightHub 3 stars
Round-trip from	$236 (Trip.com)
One-way from	$139 (Trip.com)
Popular in	May
Cheapest in	February
Average price	$357
Good round-trip deal	$318 or less
Good one-way deal	$237 or less

Provider with most accurate pricing for Toronto (YTO)-Seattle/Tacoma Intl flight deals.

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Provider most trusted by Cheapflights users for Toronto (YTO)-Seattle/Tacoma Intl flights.

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From Ontario to Washington

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One-way flight from Ontario to Washington

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Highest demand for flights based on searches. 13% potential increase in price ($59 potential increase over avg. RT price).

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Cheapest flight prices on average. 2% potential price decrease ($8 potential savings vs. average RT price).

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Average for round-trip flights in March 2025

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Price to beat on a round-trip flight from Ontario to Washington.

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Price to beat on a one-way flight from Ontario to Washington.

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Find flight deals from Ontario to Washington

Cheapest flights from Ontario to Washington
Explore the most affordable flight options available from Ontario to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 28, 2025.

Sun 5/46:00 amYHM - SEA

1 stop9h 58mWestJet

Wed 5/71:50 pmSEA - YHM

1 stop7h 51mWestJet

Deal found 3/27

$238

Wed 4/306:00 amYKF - SEA

1 stop9h 58mWestJet

Wed 5/71:50 pmSEA - YKF

1 stop7h 56mWestJet

Deal found 3/27

$242

Fri 5/308:00 amYYZ - SEA

1 stop7h 58mWestJet

Sun 6/87:05 amSEA - YYZ

1 stop7h 17mWestJet

Deal found 3/26

$242

Wed 5/287:50 amYOW - SEA

1 stop8h 08mWestJet

Wed 6/117:05 amSEA - YOW

1 stop8h 16mWestJet

Deal found 3/27

$243

Wed 4/302:00 pmYYZ - SEA

2 stops32h 51mMultiple Airlines

Wed 5/76:00 amSEA - YYZ

1 stop10h 59mMultiple Airlines

Deal found 3/27

$248

Sat 4/264:45 pmYYZ - SEA

Nonstop5h 14mAlaska Airlines

Tue 4/297:15 amSEA - YYZ

Nonstop4h 45mAlaska Airlines

Deal found 3/26

$254

Tue 7/226:00 amYHM - PDX

1 stop9h 52mWestJet

Mon 7/281:45 pmPDX - YHM

1 stop7h 56mWestJet

Deal found 3/27

$270

Mon 7/218:00 amYYZ - PDX

1 stop7h 52mWestJet

Mon 8/41:45 pmPDX - YYZ

2 stops13h 06mWestJet

Deal found 3/27

$280

Tue 4/296:00 amYHM - SEA

1 stop9h 58mMultiple Airlines

Wed 4/3012:30 pmSEA - YHM

2 stops33h 11mMultiple Airlines

Deal found 3/27

$281

Thu 5/18:00 amYYZ - PDX

1 stop7h 52mMultiple Airlines

Tue 5/67:01 pmPDX - YYZ

1 stop21h 58mMultiple Airlines

Deal found 3/27

$283

Thu 4/247:20 pmYYZ - SEA

Nonstop5h 21mAir Canada

Wed 4/306:00 amSEA - YYZ

Nonstop4h 57mAir Canada

Deal found 3/26

$290

Fri 7/47:00 amYUL - PDX

1 stop8h 52mWestJet

Tue 7/221:45 pmPDX - YUL

1 stop7h 58mWestJet

Deal found 3/27

$290

Best flights from Ontario to Washington
Discover carefully curated flight deals from Ontario to Washington that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 28, 2025.

Fri 5/26:00 amYHM - SEA

1 stop9h 58mWestJet

Mon 5/52:05 pmSEA - YHM

1 stop7h 36mWestJet

Deal found 3/27

$236

Wed 4/302:00 pmYYZ - SEA

2 stops32h 51mMultiple Airlines

Wed 5/76:00 amSEA - YYZ

1 stop10h 59mMultiple Airlines

Deal found 3/27

$248

Sat 4/264:45 pmYYZ - SEA

Nonstop5h 14mAlaska Airlines

Tue 4/297:15 amSEA - YYZ

Nonstop4h 45mAlaska Airlines

Deal found 3/26

$254

Thu 4/247:20 pmYYZ - SEA

Nonstop5h 21mAir Canada

Wed 4/306:00 amSEA - YYZ

Nonstop4h 57mAir Canada

Deal found 3/26

$290

Tue 4/157:21 pmYYZ - GEG

1 stop7h 35mDelta

Tue 4/296:00 amGEG - YYZ

1 stop9h 31mDelta

Deal found 3/27

$303

Tue 8/128:40 amYYZ - PDX

1 stop16h 46mUnited Airlines

Thu 8/217:45 amPDX - YYZ

1 stop13h 59mUnited Airlines

Deal found 3/26

$312

Fri 4/183:14 pmYYZ - PDX

1 stop10h 48mAmerican Airlines

Wed 4/2311:52 pmPDX - YYZ

1 stop9h 43mAmerican Airlines

Deal found 3/27

$333

Wed 4/304:45 pmYYZ - SEA

Nonstop5h 14mHawaiian Airlines

Wed 5/77:15 amSEA - YYZ

Nonstop4h 45mHawaiian Airlines

Deal found 3/27

$342

Wed 4/306:00 amYKF - SEA

1 stop9h 58mWestJet

Wed 5/71:50 pmSEA - YKF

1 stop7h 56mWestJet

Deal found 3/27

$242

Thu 4/103:44 pmYUL - SEA

1 stop12h 18mBritish Airways

Sun 4/135:22 amSEA - YUL

2 stops14h 22mBritish Airways

Deal found 3/27

$502

Fri 5/308:00 amYYZ - SEA

1 stop7h 58mWestJet

Sun 6/87:05 amSEA - YYZ

1 stop7h 17mWestJet

Deal found 3/26

$242

Tue 4/296:00 amYHM - SEA

1 stop9h 58mMultiple Airlines

Wed 4/3012:30 pmSEA - YHM

2 stops33h 11mMultiple Airlines

Deal found 3/27

$281

Last-minute flights from Ontario to Washington
Discover last-minute flight deals from Ontario to Washington. Data last updated March 28, 2025 and is based on user searches.

Tue 4/112:40 pmYUL - PDX

2 stops14h 04mDelta

Tue 4/811:00 pmPDX - YUL

1 stop9h 33mDelta

Deal found 3/27

$379

Tue 4/110:54 amYUL - PDX

2 stops13h 20mAmerican Airlines

Mon 4/711:52 pmPDX - YUL

1 stop8h 52mAmerican Airlines

Deal found 3/26

$399

Tue 4/18:05 amYUL - PDX

1 stop16h 49mMultiple Airlines

Tue 4/810:10 amPDX - YUL

1 stop7h 37mMultiple Airlines

Deal found 3/27

$469

Tue 4/19:45 amYUL - PDX

1 stop12h 00mAir Canada

Mon 4/711:59 pmPDX - YUL

1 stop7h 37mAir Canada

Deal found 3/26

$504

Fri 4/41:15 pmYUL - PDX

1 stop9h 59mUnited Airlines

Sun 4/65:00 amPDX - YUL

1 stop8h 59mUnited Airlines

Deal found 3/26

$378

Fri 4/47:55 amYYZ - SEA

2 stops11h 43mWestJet

Mon 4/77:13 amSEA - YYZ

2 stops10h 58mWestJet

Deal found 3/26

$569

Sun 4/67:25 pmYYZ - SEA

1 stop16h 18mMultiple Airlines

Wed 4/3012:30 pmSEA - YYZ

1 stop14h 25mMultiple Airlines

Deal found 3/27

$295

Sun 4/65:20 pmYYZ - SEA

1 stop8h 39mAmerican Airlines

Mon 4/2812:59 amSEA - YYZ

1 stop8h 41mAmerican Airlines

Deal found 3/27

$474

Mon 4/77:25 pmYYZ - PDX

1 stop17h 55mMultiple Airlines

Wed 4/92:32 pmPDX - YYZ

2 stops12h 45mMultiple Airlines

Deal found 3/26

$291

Mon 4/71:00 pmYYZ - PDX

2 stops12h 48mUnited Airlines

Wed 4/99:55 amPDX - YYZ

2 stops10h 12mUnited Airlines

Deal found 3/26

$398

Mon 4/75:00 pmYYZ - PDX

1 stop9h 44mDelta

Tue 4/812:59 amPDX - YYZ

1 stop9h 36mDelta

Deal found 3/26

$505

Mon 4/76:10 pmYOW - SEA

1 stop18h 25mMultiple Airlines

Fri 4/114:26 pmSEA - YOW

2 stops24h 46mMultiple Airlines

Deal found 3/27

$506

One-way flights from Ontario to Washington
Search for one-way flight options from Ontario to Washington. Find affordable one-way fares based on user searches. Data last updated March 28, 2025.

Sun 5/46:00 amYHM - SEA

1 stop9h 58mWestJet

Deal found 3/27

$139

Mon 5/511:00 amYYZ - PDX

3 stops29h 37mMultiple Airlines

Deal found 3/27

$153

Fri 5/26:55 amYYZ - SEA

2 stops15h 56mMultiple Airlines

Deal found 3/26

$154

Fri 5/27:00 amYTZ - SEA

2 stops14h 00mMultiple Airlines

Deal found 3/26

$156

Sun 7/206:45 amYYZ - SEA

1 stop8h 46mWestJet

Deal found 3/26

$156

Wed 8/207:00 amYUL - SEA

1 stop8h 58mWestJet

Deal found 3/27

$157

Wed 7/26:30 amYYZ - PDX

1 stop9h 22mWestJet

Deal found 3/27

$159

Thu 7/247:00 amYUL - PDX

1 stop8h 52mWestJet

Deal found 3/27

$165

Sat 9/66:00 amYKF - SEA

2 stops33h 33mWestJet

Deal found 3/27

$167

Mon 5/264:20 pmYTZ - SEA

2 stops8h 53mAir Canada

Deal found 3/27

$167

Mon 5/268:30 amYYZ - SEA

Nonstop5h 21mAir Canada

Deal found 3/27

$167

Mon 5/126:10 amYOW - SEA

2 stops33h 48mWestJet

Deal found 3/28

$173

Cheapflights Fare Finder

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

Fly from

Fly to

Route

Depart

Return

Price

HamiltonSeattle

YHM - SEA

YHMSEA

Hamilton

Sun 5/4

6:00 am-12:58 pm

1 stop9h 58m

Seattle/Tacoma Intl

Wed 5/7

1:50 pm-12:41 am

1 stop7h 51m

$238

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

Wed 4/30

6:00 am-12:58 pm

1 stop9h 58m

Seattle/Tacoma Intl

Wed 5/7

1:50 pm-12:46 am

1 stop7h 56m

$242

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Fri 5/30

8:00 am-12:58 pm

1 stop7h 58m

Seattle/Tacoma Intl

Sun 6/8

7:05 am-5:22 pm

1 stop7h 17m

$242

OttawaSeattle

YOW - SEA

YOWSEA

Ottawa

Wed 5/28

7:50 am-12:58 pm

1 stop8h 08m

Seattle/Tacoma Intl

Wed 6/11

7:05 am-6:21 pm

1 stop8h 16m

$243

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Wed 4/30

2:00 pm-7:51 pm

2 stops32h 51m

Seattle/Tacoma Intl

Wed 5/7

6:00 am-7:59 pm

1 stop10h 59m

$248

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

Sat 4/26

4:45 pm-6:59 pm

Nonstop5h 14m

Seattle/Tacoma Intl

Tue 4/29

7:15 am-3:00 pm

Nonstop4h 45m

$254

TorontoPortland

YYZ - PDX

YYZPDX

Toronto Pearson Intl

Mon 7/21

8:00 am-12:52 pm

1 stop7h 52m

Portland

Mon 8/4

1:45 pm-5:51 am

2 stops13h 06m

$280

HamiltonSeattle

YHM - SEA

YHMSEA

Hamilton

Tue 4/29

6:00 am-12:58 pm

1 stop9h 58m

Seattle/Tacoma Intl

Wed 4/30

12:30 pm-12:41 am

2 stops33h 11m

$281

TorontoPortland

YYZ - PDX

YYZPDX

Toronto Pearson Intl

Thu 5/1

8:00 am-12:52 pm

1 stop7h 52m

Portland

Tue 5/6

7:01 pm-7:59 pm

1 stop21h 58m

$283

HamiltonPortland

YHM - PDX

YHMPDX

Hamilton

Mon 5/5

6:00 am-12:52 pm

1 stop9h 52m

Portland

Thu 5/8

1:45 pm-12:41 am

1 stop7h 56m

$283

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/27

Showing 1-10 of 60 results

...

Best time to book a flight from Ontario to Washington

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

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 Washington

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

Currently, January is the cheapest month in which you can book a flight from Region of Ontario to State of Washington (average of $238). Flying from Region of Ontario to State of Washington in July is currently the most expensive (average of $411). 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 WA?

When flying from Region of Ontario to State of Washington, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

Rainfall in Washington by month

In terms of precipitation, rainfall in State of Washington ranges from 0.7 - 6.6 inches per month. November is typically the wettest month, when rainfall can reach 6.6 in. July is typically the driest time to visit State of Washington when rainfall is around 0.7 in.

Temperature in Washington by month

If weather is an important factor for your trip to State of Washington, 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 66.2 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 41.0 F).

Reviews of airlines servicing Washington

Read reviews from past customers who have flown Alaska Airlines, Delta and Hawaiian Airlines from Ontario to Washington. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.

Alaska Airlines

8.0

Very good

9,798 reviews

Reviews

1 / 20

10.0

Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Alaska Airlines

8.0

Very good

9,798 reviews

Alaska Airlines

8.0

Very good

9,798 reviews

Reviews

1 / 20

10.0

Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Delta

8.0

Very good

7,896 reviews

Alaska Airlines

8.0

Very good

9,798 reviews

Reviews

1 / 20

10.0

Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Hawaiian Airlines

7.9

Good

2,336 reviews

Alaska Airlines

8.0

Very good

9,798 reviews

Reviews

1 / 20

10.0

Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

United Airlines

7.4

Good

8,603 reviews

Alaska Airlines

8.0

Very good

9,798 reviews

Reviews

1 / 20

10.0

Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

American Airlines

7.2

Good

10,000 reviews

Alaska Airlines

8.0

Very good

9,798 reviews

Reviews

1 / 20

10.0

Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Related info for your journey

What are the cheapest airlines to fly from Region of Ontario to State of Washington one-way?
The cheapest airlines for a one-way flight from Region of Ontario to State of Washington are WestJet ($139), Air Canada ($167), and Alaska Airlines ($175).
Can I find deals for flights from Ontario to Washington that include hotel bookings?
Yes. In addition to deals on Ontario to Washington flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Ontario to Washington?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Washington.
Can I find deals for business class flights from Ontario to Washington?
Yes. Cheapflights offers flight deals from Ontario to Washington 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 State of Washington?
Currently, January is the cheapest month in which you can book a flight from Region of Ontario to State of Washington (average of $238). Flying from Region of Ontario to State of Washington in July is currently the most expensive (average of $411). 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

Browse thousands of different options on Cheapflights for your next trip

Top 6 airlines flying from Ontario to Washington

Airline	Cheapest	Average	Flexibility	On-time
Air Canada	Cheapest$122	Average$457	FlexibilityNo cancel fee	On-time67%
WestJet	Cheapest$164	Average$412	FlexibilityNo cancel fee	On-time60%
Alaska Airlines	Cheapest$239	Average$414	FlexibilityNo cancel fee	On-time75%
United Airlines	Cheapest$240	Average$439	FlexibilityNo cancel fee	On-time69%
Delta	Cheapest$292	Average$451	FlexibilityNo cancel fee	On-timeN/A
American Airlines	Cheapest$393	Average$653	FlexibilityNo cancel fee	On-time71%

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$139+ Cheap flights from Ontario to Washington

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 5/4. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Ontario to Washington with Cheapflights

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Cheap flight deals from Ontario to Washington

Keep the following information in mind while searching for Ontario to Washington flight deals. Data was last updated March 28, 2025.

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from Ontario to Washington

Cheapest flights from Ontario to WashingtonExplore the most affordable flight options available from Ontario to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 28, 2025.

Explore the most affordable flight options available from Ontario to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 28, 2025.

Cheapflights Fare Finder

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

Best time to book a flight from Ontario to Washington

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

Cheapflights Insights

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

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

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

Find hourly flight availability from Ontario to Washington. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 28, 2025.

Rainfall in Washington by month

Plan your trip to Washington by taking into account the average rainfall totals by month.

Temperature in Washington by month

Plan your trip to Washington by taking into account the average temperature totals by month.

Reviews of airlines servicing Washington

Read reviews from past customers who have flown Alaska Airlines, Delta and Hawaiian Airlines from Ontario to Washington. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from Ontario to Washington. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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

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

How can I find direct flights from Ontario to Washington?

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

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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Ontario to Washington

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

Top 6 airlines flying from Ontario to Washington

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Cheapest flights from Ontario to Washington
Explore the most affordable flight options available from Ontario to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 28, 2025.