$73 Find Cheap Flights from Seattle to Ontario

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Seattle to Ontario departing on 3/11. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Ontario

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Seattle to Ontario, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Seattle to Ontario, as well as popular online travel agencies
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Flight Deals

Cheap Flights from Seattle to Ontario

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Toronto
Toronto2 stops$190
Ottawa
Ottawa1 stop$319
Thunder Bay
Thunder Bay2 stops$395
London
London2 stops$312
Timmins
Timmins1 stop$720
Toronto
Toronto2 stops$190
Ottawa
Ottawa1 stop$319
Thunder Bay
Thunder Bay2 stops$395
London
London2 stops$312
Timmins
Timmins1 stop$720

Book Cheap Seattle to Ontario Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Seattle to Ontario that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Seattle to Ontario

Sat, May 9 - Mon, May 11
WestJet Logo
10:30 am - 11:59 pm
SEA
-
YYZ
10h 29m
2 stops
WestJet Logo
1:30 pm - 6:45 pm
YYZ
-
SEA
8h 15m
1 stop
$190WestJet
Fri, May 1 - Mon, May 4
WestJet Logo
7:35 pm - 5:45 am
SEA
-
YYZ
7h 10m
1 stop
WestJet Logo
1:30 pm - 6:45 pm
YYZ
-
SEA
8h 15m
1 stop
$191WestJet
Sat, May 9 - Mon, May 11
WestJet Logo
10:30 am - 10:45 pm
SEA
-
YYZ
9h 15m
1 stop
WestJet Logo
1:30 pm - 6:45 pm
YYZ
-
SEA
8h 15m
1 stop
$192WestJet
Thu, May 28 - Tue, Jun 2
WestJet Logo
7:35 pm - 6:55 am
SEA
-
YYZ
8h 20m
1 stop
WestJet Logo
1:30 pm - 6:45 pm
YYZ
-
SEA
8h 15m
1 stop
$195WestJet
Sun, Mar 29 - Sun, Apr 5
Multiple Airlines Logo
5:50 am - 6:00 pm
SEA
-
YYZ
9h 10m
1 stop
Multiple Airlines Logo
7:45 am - 2:19 pm
YYZ
-
SEA
9h 34m
1 stop
$207Multiple Airlines
Thu, Mar 12 - Thu, Mar 19
Air Canada Logo
5:40 am - 6:10 pm
SEA
-
YTZ
9h 30m
2 stops
Air Canada Logo
12:30 pm - 10:57 pm
YTZ
-
SEA
13h 27m
2 stops
$283Air Canada
Thu, Mar 5 - Sun, Mar 8
Air Canada Logo
8:00 pm - 8:46 am
SEA
-
YXU
9h 46m
2 stops
Air Canada Logo
5:40 pm - 10:16 pm
YXU
-
SEA
7h 36m
1 stop
$312Air Canada
Thu, Jun 4 - Sat, Jun 6
United Airlines Logo
11:52 pm - 10:06 am
SEA
-
YTZ
7h 14m
1 stop
United Airlines Logo
2:55 pm - 8:45 pm
YTZ
-
SEA
8h 50m
1 stop
$344United Airlines
Mon, Apr 13 - Sat, Apr 18
Multiple Airlines Logo
11:10 pm - 2:44 pm
SEA
-
YOW
12h 34m
1 stop
Multiple Airlines Logo
5:40 am - 2:19 pm
YOW
-
SEA
35h 39m
2 stops
$366Multiple Airlines
Sat, Feb 28 - Tue, Mar 31
United Airlines Logo
11:59 pm - 10:26 am
SEA
-
YOW
7h 27m
1 stop
United Airlines Logo
5:20 pm - 10:37 pm
YOW
-
SEA
8h 17m
1 stop
$381United Airlines
Booking Insights

KAYAK's insights & trends for Seattle to Ontario flights

Get data-powered insights and trends into flights from Seattle to Ontario to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from Seattle to Region of Ontario?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Seattle to Region of Ontario departing in May.

What is the cheapest Seattle to Ontario flight route?

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest ticket to Ontario from Seattle found in the last 72 hours was to Toronto, at $217 round-trip. The most popular route is from Seattle (SEA) to Toronto Pearson Intl Airport (YYZ), and the cheapest round-trip airline ticket found on this route in the last 72 hours was $217.

Can I save money by flying with a layover from Seattle to Ontario?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

No, with an average price for the route of $344, prices are generally cheapest when you fly direct.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Seattle to Ontario, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Seattle to Ontario is January, when tickets cost $250 (return) on average. On the other hand, the most expensive months are June and July, when the average cost of round-trip tickets is $476 and $452 respectively.

What’s the cheapest day of the week to fly from Seattle to Ontario?

The average price of all round-trip flights from Seattle to Ontario clicked on KAYAK for each day over the last 12 months.

For Seattle to Ontario, Tuesday is the cheapest day to fly on average and Saturday is the most expensive. Flying from Ontario back to Seattle, the best deals are generally found on Thursday, with Sunday being the most expensive.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Seattle to Ontario, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Seattle to Ontario, you should book around 3 weeks before departure, which saves you about 54% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 24 weeks before departure.

Good to know

Low seasonFebruary
Cheapest flight$73
Best time to beat the crowds with an average 13% drop in price.
Most popular time to fly and prices are also 1% lower on average.
Flight from Seattle to Toronto Pearson Airport

FAQs - booking Ontario flights

  • How does KAYAK find such low prices on flights from Seattle to Ontario?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Seattle to Ontario.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Seattle to Ontario?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Seattle to Ontario is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Seattle to Ontario?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly from Seattle to Ontario with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Seattle to Ontario?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying from Seattle to Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • What is the cheapest time of day to fly to Ontario?

    The cheapest time of day to fly to Ontario is generally in the morning, when round-trip flights cost $603 on average. The most expensive time of day to fly to Ontario is generally in the morning, which is peak travel time and where the average cost of a ticket is $603.

Reviews of the top 5 airlines serving from Seattle to Ontario

 
See real verified KAYAK customer reviews for airlines flying from Seattle to Ontario. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Seattle to Ontario? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
Alaska AirlinesOverall score based on 11882 reviews
7.1Food
8.1Boarding
7.8Comfort
7.0Entertainment
8.5Crew
Airline reviews

I paid for the WiFi and it didn’t work during the whole flight

2.0 MediocreGloria, Feb 2026
SEA - SNA
Read more Alaska Airlines reviews

I paid for the WiFi and it didn’t work during the whole flight

Impressed that Alaska Air(for our domestic flight) transferred our checked bags to EVA (for our international flights) so that we didn't have to handle them, & we just picked them up at our final destination.

I enjoyed the movie selection. I’m glad I saw ahead of time to bring personal ear buds. I don’t normally have them with me and airlines used to give them out.

man & woman back side flight attendant was very rude. I live in Seattle. I use a lot of time Alaska flights. I always like them for fact that my favorite airline employees very rude. It’s disappointing. .

Great experience, staff and crew were very professional, friendly and helpful!

I think Alaska should start including free meals on these longer trips.

Wheelchair assistance was excellent. I had a saver fare, but was given a seat in Premium. So very nice!! Extra legroom, complimentary beer. The flight crew was very nice and efficient. The gate agent in Seattle double checked to make sure I was able to board the plane all right while using my cane. I boarded first. So considerate! The flight was smooth, and right on time.

There is nothing critical to complain about but I would say the snacks are pretty bad Airline staff could be aggressive the way they move through the aisles and the plane I also got hustled for a small wallet size men bag and force the consolidated with my carry on item we're talking about a wallet size bag.

Departed on time and had an efficient boarding process. The inflight wifi was not working on one of the flights.

How can I review what was denied to me. Instead of offering to let me pay for the ticket I got booted of my flight with no way home and no choice but to purchase another ticket for 12 hours later. Filing a complaint with the DOT

Flight was delayed and no reasons provided. After the passengers were boarded, the crew made announcement that the captain has jot arrived and he would take another 15 mins. All passengers patiently sat until the captain came and started. Terrible experience!

Flight was delayed. No information on why it was delayed. After we boarded the flight, , the crew made announcement that the captain hs not arrived and he will take 15 mins more to arrive. Passengers were just sitting patiently for the captain to arrive and start, Terrible experience.

Totally worth the miles to upgrade to Delta Comfort. Plenty of legroom.

This was my first time flying Delta ever and I had a great experience!

Smallest leg room I've ever had on a plane.

They took all carry-on luggage from Groups 6 -9 - I was group 5 and waiting in line to board - they made me check my luggage too. That then went to baggage claim and delayed departure from the airport. There was overhead room in my seating area - Delta over reacted. Also, had a gentleman next to me that took up 1/2 my seat.

Excellent!!! Aeromexico is a great airline. What was not that good is the service provided by Kayak. It is never clear and not easy to manage.

Flight delay was frustrating, also you cannot checkin online without delta app, web browser check-in throw errors

The gate agent was most helpful in getting me on to fly standby. I greatly appreciate it.

bulkhead seat had very little legroom - even in bsiness class.

Wifi took a while to kick in and we had a maintenance issue that took over 40 mins at the gate in Washington before pulling back

Not United Airlines' fault. It's ORL airport's fault.

United overall experience is great these days. Airport experience was very organized. Staff on flight were great. App and information as good as it gets.

Very nice flight love the small aircraft. We had a wonderful flight attendant. Nice to see someone that really enjoys her job. Don't have her name but had a southern accent.

Seats in waiting area and on plane hard as rock. Fast internet on the flight was great! Crew was kind.

United needs to step up their game. Delayed flight leaving Seattle, San Francisco. Older aircraft, not very comfortable.

Not the fault of United—weather, reroute around weather, time sitting on tarmac, arrived couple hours late, too late for train into city necessitating a much pricier cab but weather…can’t be helped.

Flight was good but there are way to many announcements for credit cards etc.

I had no checked baggage but was required to hand over carry on baggage at the door of the plane. There was a lot of overboard space in the plane and I was one of the last ones. I ran to get my carry on but it was gone. I was given back at the plane door in Toronto, so the wait was not as long as it would have been at the carousel.

We had a layover from YVR to Denver. We bought 4 bottles of Absolut Vodka at the YVR Duty Free for $116.20, after going through security and American Customs Pre Clearance at YVR, Vancouver. When we landed in Denver, United put us behind the American Customs as well as TSA again for some reason. We were forced to go through American Customs and TSA again. TSA confiscated our rightfully owned Duty Free Absolut Vodka bottles. Because United incorrectly forced our flight behind American border and TSA again, we missed the connecting flight. After United put us on a later flight, we eventually arrived in Chicago very late, with hardly any sleep. I am looking for compensation from United for our incorrectly confiscated Absolut Vodka bottles worth $116.20, as well as compensation for incorrectly putting us behind American Customs and TSA again, causing us to miss our connecting flight, making us arrive extremely late in Chicago.

I didn't think about not having the right app for wifi because my connecting flight was with Westjet and when I took off from Seattle I was thinking I would use my wifi, but realized I couldn't on my Westjet app and I did not have Delta's app downloaded.

Everything was good except for flight delay, but it was because of the snow storm in the arrival airport.

The flight was cancelled less than 24 hours before departure. The alternate flight was a day later going from Grenada to Toronto to Vancouver to Calgary to Montreal. 2 days in the air. Not serious, Very bad service

I like the wider seats, Plus lots of legroom, Lacking entertainment, no tv or screen to play with

Liked in-flight wifi Did not like - nothing to complain, really. All good

The keg from Edmonton to Toronto My wife found it very cold. Other than that great flight.

Smooth flight Staff were courteous and welcoming upon entering and exiting the plane Pilot and crew provided frequent updates Leg space was not pleasant but manageable

Everything was good except I was a bit disappointed that I had to pay US $150 for bags.

Flight itself good .Landing at terminal3 and connections to terminal1,it is connections nightmare,specially for disable person

The seats very Uncomfortable, no meal and no entertainment for a 4Hours flight. Smooth Flight, Great Take off and landing. Superb crew!

The last 3 hours it was freezing cold in row 56. Multiple people had their winter coats on and were utilizing the blankets provided by the airline. I also did not have easy access to figure out how to book my food allergy and advance for my meals. Most of everything I received was something I couldn't eat. This needs to be made more accessible. Also, I'm 5'10 which is the average height of the American male. I flew from Philadelphia to Toronto and then to Tokyo and the seats were absolutely unbearable. For that long of a flight it is impossible to get comfortable when doing anything. Flights need to have more space and stop prioritizing costs over people.

Was delayed at every point/ connection. Luggages missing for 5days. Had no medications for diabetes and high B/p. when bags where finally delivered on the 30th, the insulin and ozempic were no longer patent, as the ice pack had since dissolved and the authenticity of the med is now questionable, since they must be refrigerated. Please have them refund my bag fees. I should sue them for all the inconveniences caused to me.

The plane was delayed substantially due to a mechanical problem, that being said, the airline was very fair with providing a meal coupon for us. I would rather arrive late on a mechanically sound plane than the alternative. The food served in the plane was just awful, however and I recommend a new catering company.

I waiting for 2 hrs to retrieve my luggage. Didn't get home till 3am.

The flight left late and I didn’t get a glass of bubbly upon boarding (which I’m used to when booking business class on other flights), but otherwise it was a pleasant flight with lovely, helpful crew members and I enjoyed my meal.

Flight was canceled for a reason they knew hours before but did not mention. Next the gate chnage from 37 to 38 at least 10 times. Ridiculous.

It was just fine. I managed to make all my connection too sbut had trouble in Munich with no wheel chair and trouble trying to get help from the airport people to get to the other terminal for my flight. Finally a wonderful lady Amelia, helped me to make my flight connection Timon with zero time to spare.

Super experience. Earlier than schedule departure and arrival. Baggage handling was very good

I would like to get my money back. I flight was 4 hours late on the way to detroit, And same on my way back to Brussels they cancelled my flight and give me an other ticket and i had to wait 5 hours.

All attendents were very efficient, pleasant and happy. Everything went smoothly. The seats could have been wider. There could have been more free food instead of just one small bar.

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

Information on your arrival and departure airports