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

$99 is the cheapest one-way deal found within the past few days, from WestJet. You may also be able to find cheap deals on Air Canada and Delta, with prices starting from $164 and $176, respectively.

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

When deciding which route to take from Region of Ontario to Seattle consider Toronto Pearson Intl - Seattle/Tacoma Intl, Montreal Pierre Elliott Trudeau Intl - Seattle/Tacoma Intl or Hamilton - Seattle/Tacoma Intl as they are the most popular.

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

On average you can expect to pay $349 for a flight from Region of Ontario to Seattle. The cheapest flight overall is $154 while the most popular route, (Toronto Pearson Intl - Seattle/Tacoma Intl) is currently priced at $215.

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 Air Tahiti Nui (99%), Alaska Airlines (85%) or Hawaiian Airlines (85%) 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?

Consider American Airlines, Air Canada or Alaska Airlines when booking your flight. These represent the most popular airlines when flying from Region of Ontario to Seattle.

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

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 79% on flights from Region of Ontario to Seattle 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 $753.

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

February can be a great time to fly to Seattle from Region of Ontario with a flight ticket averaging about $375. Cheapflights users have found deals in the month of February for as cheap as $212. The most expensive prices can be found in the month of July.

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

Seattle/Tacoma Intl (SEA), located 11.4 mi from the city center, is the airport you fly into when you book flights from 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.

$99+ Flights from Ontario to Seattle

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Cheap flight deals from Ontario to Seattle

Most accurate provider	FlightHub 3 stars
Most trusted provider	eDreams 3 stars
Round-trip from	$155 (Trip.com)
One-way from	$99 (Trip.com)
Popular in	July
Cheapest in	February
Average price	$396
Good round-trip deal	$336 or less
Good one-way deal	$176 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 Seattle/Tacoma Intl

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One-way flight from Ontario to Seattle/Tacoma Intl

Search Deals

Highest demand for flights based on searches. 10% potential increase in price ($44 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 1% potential price decrease ($8 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in April 2025

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.

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Find flight deals from Ontario to Seattle

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 abril 16, 2025.

jue. 6/56:00 amYHM - SEA

1 stop9h 58mWestJet

jue. 6/121:50 pmSEA - YHM

1 stop7h 51mWestJet

Deal found 4/14

$155

sáb. 5/36:00 amYHM - SEA

1 stop9h 58mMultiple Airlines

mar. 5/136:00 amSEA - YHM

2 stops15h 41mMultiple Airlines

Deal found 4/15

$179

vie. 8/158:00 pmYXU - SEA

1 stop27h 28mWestJet

vie. 8/227:35 pmSEA - YXU

1 stop6h 39mWestJet

Deal found 4/15

$182

vie. 8/156:15 amYXU - SEA

1 stop7h 55mUnited Airlines

vie. 8/225:00 pmSEA - YXU

2 stops21h 07mUnited Airlines

Deal found 4/15

$200

dom. 7/276:30 amYYZ - SEA

1 stop9h 28mWestJet

lun. 8/42:05 pmSEA - YYZ

1 stop7h 19mWestJet

Deal found 4/16

$236

jue. 5/86:00 amYKF - SEA

3 stops35h 25mMultiple Airlines

lun. 5/123:20 pmSEA - YKF

2 stops30h 26mMultiple Airlines

Deal found 4/15

$244

sáb. 5/36:30 amYYZ - SEA

1 stop9h 28mMultiple Airlines

vie. 5/96:00 amSEA - YYZ

2 stops21h 14mMultiple Airlines

Deal found 4/16

$245

mié. 9/176:00 amYKF - SEA

1 stop9h 59mWestJet

mar. 9/232:05 pmSEA - YKF

1 stop7h 40mWestJet

Deal found 4/15

$246

sáb. 5/316:10 amYOW - SEA

2 stops9h 48mWestJet

sáb. 6/77:05 amSEA - YOW

1 stop8h 16mWestJet

Deal found 4/15

$254

dom. 5/186:00 amYXU - SEA

1 stop9h 58mMultiple Airlines

dom. 5/256:25 amSEA - YXU

2 stops19h 49mMultiple Airlines

Deal found 4/14

$265

sáb. 5/316:00 pmYOW - SEA

1 stop7h 13mAir Canada

sáb. 6/77:20 amSEA - YOW

1 stop9h 57mAir Canada

Deal found 4/15

$269

dom. 5/119:55 amYXU - SEA

2 stops12h 42mAir Canada

jue. 5/157:20 amSEA - YXU

2 stops22h 59mAir Canada

Deal found 4/15

$274

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 abril 16, 2025.

jue. 6/56:00 amYHM - SEA

1 stop9h 58mWestJet

jue. 6/121:50 pmSEA - YHM

1 stop7h 51mWestJet

Deal found 4/14

$155

sáb. 5/36:00 amYHM - SEA

1 stop9h 58mMultiple Airlines

mar. 5/136:00 amSEA - YHM

2 stops15h 41mMultiple Airlines

Deal found 4/15

$179

vie. 8/156:15 amYXU - SEA

1 stop7h 55mUnited Airlines

vie. 8/225:00 pmSEA - YXU

2 stops18h 57mUnited Airlines

Deal found 4/16

$200

sáb. 5/316:00 pmYOW - SEA

1 stop7h 13mAir Canada

sáb. 6/77:20 amSEA - YOW

1 stop9h 57mAir Canada

Deal found 4/15

$269

vie. 5/24:45 pmYYZ - SEA

Nonstop5h 14mAlaska Airlines

mié. 5/77:15 amSEA - YYZ

Nonstop4h 45mAlaska Airlines

Deal found 4/16

$286

jue. 5/812:15 pmYYZ - SEA

1 stop8h 35mDelta

dom. 5/186:00 amSEA - YYZ

1 stop8h 15mDelta

Deal found 4/15

$296

jue. 5/111:45 amYYZ - SEA

1 stop12h 19mAmerican Airlines

jue. 5/151:10 amSEA - YYZ

1 stop12h 15mAmerican Airlines

Deal found 4/16

$311

vie. 8/158:00 pmYXU - SEA

1 stop27h 28mWestJet

vie. 8/227:05 amSEA - YXU

1 stop9h 04mWestJet

Deal found 4/16

$180

jue. 5/86:00 amYKF - SEA

3 stops35h 25mMultiple Airlines

lun. 5/123:20 pmSEA - YKF

2 stops30h 26mMultiple Airlines

Deal found 4/15

$244

mié. 5/211:30 pmYYZ - SEA

1 stop8h 40mWestJet

mié. 5/281:50 pmSEA - YYZ

1 stop7h 36mWestJet

Deal found 4/15

$244

mar. 5/278:00 amYYZ - SEA

1 stop7h 58mMultiple Airlines

jue. 5/296:00 amSEA - YYZ

2 stops13h 56mMultiple Airlines

Deal found 4/15

$245

mié. 5/2112:25 pmYTZ - SEA

1 stop10h 12mAir Canada

mar. 5/277:20 amSEA - YTZ

1 stop9h 30mAir Canada

Deal found 4/14

$286

Last-minute flights from Ontario to Seattle
Discover last-minute flight deals from Ontario to Seattle. Data last updated abril 16, 2025 and is based on user searches.

lun. 4/217:00 amYYZ - SEA

2 stops44h 44mMultiple Airlines

vie. 5/21:50 pmSEA - YYZ

1 stop7h 36mMultiple Airlines

Deal found 4/16

$359

vie. 4/256:15 amYYZ - SEA

1 stop9h 11mDelta

dom. 4/275:30 amSEA - YYZ

1 stop8h 08mDelta

Deal found 4/14

$364

vie. 4/256:20 pmYYZ - SEA

1 stop7h 49mAmerican Airlines

sáb. 4/2612:59 amSEA - YYZ

1 stop8h 41mAmerican Airlines

Deal found 4/15

$453

sáb. 4/264:45 pmYYZ - SEA

Nonstop5h 14mAlaska Airlines

sáb. 5/37:15 amSEA - YYZ

Nonstop4h 45mAlaska Airlines

Deal found 4/16

$313

sáb. 4/262:30 pmYYZ - SEA

1 stop8h 51mUnited Airlines

sáb. 5/35:40 pmSEA - YYZ

1 stop10h 20mUnited Airlines

Deal found 4/16

$337

sáb. 4/264:15 pmYUL - SEA

1 stop8h 26mAir Canada

jue. 5/17:20 amSEA - YUL

Nonstop5h 10mAir Canada

Deal found 4/14

$365

sáb. 4/262:20 pmYUL - SEA

1 stop9h 01mUnited Airlines

jue. 5/16:15 amSEA - YUL

1 stop11h 15mUnited Airlines

Deal found 4/16

$380

sáb. 4/263:06 pmYUL - SEA

1 stop10h 14mDelta

sáb. 5/310:30 pmSEA - YUL

1 stop10h 07mDelta

Deal found 4/15

$381

sáb. 4/2612:55 pmYUL - SEA

1 stop12h 04mAmerican Airlines

vie. 5/212:59 amSEA - YUL

1 stop10h 56mAmerican Airlines

Deal found 4/15

$390

sáb. 4/262:35 pmYUL - SEA

2 stops30h 48mMultiple Airlines

jue. 5/17:35 pmSEA - YUL

2 stops26h 02mMultiple Airlines

Deal found 4/14

$469

sáb. 4/266:30 amYYZ - SEA

2 stops13h 08mWestJet

sáb. 5/38:25 amSEA - YYZ

2 stops13h 10mWestJet

Deal found 4/16

$523

sáb. 4/263:25 pmYTZ - SEA

2 stops23h 10mMultiple Airlines

dom. 4/278:56 pmSEA - YTZ

2 stops18h 57mMultiple Airlines

Deal found 4/16

$524

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 abril 16, 2025.

sáb. 5/246:00 amYHM - SEA

1 stop9h 58mWestJet

Deal found 4/15

$99

mié. 5/77:50 amYOW - SEA

1 stop8h 08mWestJet

Deal found 4/16

$152

dom. 5/46:00 amYHM - SEA

2 stops32h 35mMultiple Airlines

Deal found 4/16

$155

mié. 5/76:00 amYOW - SEA

2 stops21h 10mMultiple Airlines

Deal found 4/16

$160

vie. 5/306:45 amYUL - SEA

2 stops33h 13mWestJet

Deal found 4/15

$160

mar. 5/66:00 pmYOW - SEA

1 stop7h 13mAir Canada

Deal found 4/16

$164

mar. 5/64:40 pmYTZ - SEA

3 stops24h 29mMultiple Airlines

Deal found 4/14

$170

mar. 5/610:20 amYTZ - SEA

2 stops12h 17mAir Canada

Deal found 4/14

$171

sáb. 5/310:20 pmYYZ - SEA

2 stops40h 15mMultiple Airlines

Deal found 4/15

$171

jue. 5/112:00 pmYYZ - SEA

1 stop10h 37mAir Canada

Deal found 4/14

$172

vie. 5/306:45 amYUL - SEA

2 stops32h 01mMultiple Airlines

Deal found 4/15

$174

sáb. 5/310:20 pmYYZ - SEA

2 stops17h 38mWestJet

Deal found 4/15

$174

Cheapflights Fare Finder

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

Fly from

Fly to

Route

Depart

Return

Price

HamiltonSeattle

YHM - SEA

YHMSEA

Hamilton

jue. 6/5

6:00 am-12:58 pm

1 stop9h 58m

Seattle/Tacoma Intl

jue. 6/12

1:50 pm-12:41 am

1 stop7h 51m

$155

HamiltonSeattle

YHM - SEA

YHMSEA

Hamilton

sáb. 5/3

6:00 am-12:58 pm

1 stop9h 58m

Seattle/Tacoma Intl

mar. 5/13

6:00 am-12:41 am

2 stops15h 41m

$179

LondonSeattle

YXU - SEA

YXUSEA

London

vie. 8/15

8:00 pm-8:28 pm

1 stop27h 28m

Seattle/Tacoma Intl

vie. 8/22

7:35 pm-5:14 am

1 stop6h 39m

$182

LondonSeattle

YXU - SEA

YXUSEA

London

vie. 8/15

6:15 am-11:10 am

1 stop7h 55m

Seattle/Tacoma Intl

vie. 8/22

5:00 pm-5:07 pm

2 stops21h 07m

$200

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

dom. 7/27

6:30 am-12:58 pm

1 stop9h 28m

Seattle/Tacoma Intl

lun. 8/4

2:05 pm-12:24 am

1 stop7h 19m

$236

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

jue. 5/8

6:00 am-2:25 pm

3 stops35h 25m

Seattle/Tacoma Intl

lun. 5/12

3:20 pm-12:46 am

2 stops30h 26m

$244

TorontoSeattle

YYZ - SEA

YYZSEA

Toronto Pearson Intl

sáb. 5/3

6:30 am-12:58 pm

1 stop9h 28m

Seattle/Tacoma Intl

vie. 5/9

6:00 am-6:14 am

2 stops21h 14m

$245

TorontoSeattle

YKF - SEA

YKFSEA

Toronto Region of Waterloo Intl

mié. 9/17

6:00 am-12:59 pm

1 stop9h 59m

Seattle/Tacoma Intl

mar. 9/23

2:05 pm-12:45 am

1 stop7h 40m

$246

OttawaSeattle

YOW - SEA

YOWSEA

Ottawa

sáb. 5/31

6:10 am-12:58 pm

2 stops9h 48m

Seattle/Tacoma Intl

sáb. 6/7

7:05 am-6:21 pm

1 stop8h 16m

$254

LondonSeattle

YXU - SEA

YXUSEA

London

dom. 5/18

6:00 am-12:58 pm

1 stop9h 58m

Seattle/Tacoma Intl

dom. 5/25

6:25 am-5:14 am

2 stops19h 49m

$265

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/15

Showing 1-10 of 54 results

...

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.

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

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

Currently, January is the cheapest month in which you can book a flight from Region of Ontario to Seattle (average of $238). Flying from Region of Ontario to Seattle 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 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 Wednesday (6 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (2 on average).

Rainfall in Seattle by month

In terms of precipitation, rainfall in Seattle 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 Seattle when rainfall is around 0.7 in.

Temperature in Seattle by month

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 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 Seattle

Read reviews from past customers who have flown Alaska Airlines, Delta and United Airlines from Ontario to Seattle. 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

9,882 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

9,882 reviews

Alaska Airlines

8.0

Very good

9,882 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

7,917 reviews

Alaska Airlines

8.0

Very good

9,882 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

8,665 reviews

Alaska Airlines

8.0

Very good

9,882 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

9,882 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

WestJet

7.2

Good

2,806 reviews

Alaska Airlines

8.0

Very good

9,882 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 airport do you fly into for flights to Seattle from Ontario?
Seattle/Tacoma Intl (SEA), located 11.4 mi from the city center, is the airport you fly into when you book flights from Ontario to Seattle.
What are the cheapest airlines to fly from Region of Ontario to Seattle one-way?
$99 is the cheapest one-way deal found within the past few days, from WestJet. You may also be able to find cheap deals on Air Canada and Delta, with prices starting from $164 and $176, respectively.
What are the most popular routes from Region of Ontario to Seattle?
When deciding which route to take from Region of Ontario to Seattle consider Toronto Pearson Intl - Seattle/Tacoma Intl, Montreal Pierre Elliott Trudeau Intl - Seattle/Tacoma Intl or Hamilton - Seattle/Tacoma Intl as they are the most popular.
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 Air Tahiti Nui (99%), Alaska Airlines (85%) or Hawaiian Airlines (85%) 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?
On average you can expect to pay $349 for a flight from Region of Ontario to Seattle. The cheapest flight overall is $154 while the most popular route, (Toronto Pearson Intl - Seattle/Tacoma Intl) is currently priced at $215.
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, January is the cheapest month in which you can book a flight from Region of Ontario to Seattle (average of $238). Flying from Region of Ontario to Seattle 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

SeaTac

Tukwila

Tacoma

Renton

Lakewood

Ocean Shores

Lacey

Leavenworth

Federal Way

Olympia

Shoreline

Cle Elum

Centralia

Aberdeen

Kent

Lynnwood

Shelton

Silverdale

Redmond

Issaquah

Browse thousands of different options on Cheapflights for your next trip

Top 6 airlines flying from Ontario to Seattle

Airline	Cheapest	Average	Flexibility	On-time
Air Canada	Cheapest$122	Average$450	FlexibilityNo cancel fee	On-time67%
WestJet	Cheapest$141	Average$375	FlexibilityNo cancel fee	On-time60%
Alaska Airlines	Cheapest$239	Average$412	FlexibilityNo cancel fee	On-time75%
United Airlines	Cheapest$240	Average$442	FlexibilityNo cancel fee	On-time69%
Delta	Cheapest$292	Average$421	FlexibilityNo cancel fee	On-timeN/A
American Airlines	Cheapest$393	Average$653	FlexibilityNo cancel fee	On-time71%

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$99+ Cheap flights from Ontario to Seattle (SEA)

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 5/24. Fares are subject to change and may not be available on all flights or dates of travel.

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Cheap flight deals from Ontario to Seattle

Keep the following information in mind while searching for Ontario to Seattle flight deals. Data was last updated abril 16, 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 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 abril 16, 2025.

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 abril 16, 2025.

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

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

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 abril 16, 2025.

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 abril 16, 2025.

Rainfall in Seattle by month

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

Temperature in Seattle by month

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

Reviews of airlines servicing Seattle

Read reviews from past customers who have flown Alaska Airlines, Delta and United Airlines from Ontario to Seattle. 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 Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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

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?

Traveling to a place near Ontario?

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.

Top 6 airlines flying from Ontario to Seattle

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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 abril 16, 2025.