C$ 128 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 11/3. 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

Best Ontario Flight Deals from Seattle

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Toronto
TorontodirectC$ 304
Ottawa
Ottawa2 stopsC$ 414
London
London1 stopC$ 410
Toronto
TorontodirectC$ 304
Ottawa
Ottawa2 stopsC$ 414
London
London1 stopC$ 410

Cheap Flights from Seattle to Ontario

 
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, 28 Feb - Sat, 7 Mar
Air Canada Logo
8:00 a.m. - 3:43 p.m.
SEA
-
YYZ
4h 43mdirect
Air Canada Logo
8:00 a.m. - 3:01 p.m.
YYZ
-
SEA
10h 01m
2 stops
C$ 304Air Canada
Sat, 21 Feb - Sat, 28 Feb
Air Canada Logo
8:00 a.m. - 3:43 p.m.
SEA
-
YYZ
4h 43mdirect
Air Canada Logo
8:00 a.m. - 2:31 p.m.
YYZ
-
SEA
9h 31m
1 stop
C$ 307Air Canada
Sat, 21 Feb - Sat, 28 Feb
Multiple Airlines Logo
8:00 a.m. - 3:43 p.m.
SEA
-
YYZ
4h 43mdirect
Multiple Airlines Logo
4:45 p.m. - 7:18 p.m.
YYZ
-
SEA
5h 33mdirect
C$ 315Multiple Airlines
Sat, 21 Feb - Sat, 28 Feb
Multiple Airlines Logo
3:20 p.m. - 5:58 a.m.
SEA
-
YYZ
11h 38m
2 stops
Multiple Airlines Logo
5:55 p.m. - 10:57 p.m.
YYZ
-
SEA
8h 02m
1 stop
C$ 316Multiple Airlines
Tue, 17 Mar - Tue, 7 Apr
Multiple Airlines Logo
7:55 a.m. - 3:35 p.m.
SEA
-
YYZ
4h 40mdirect
Multiple Airlines Logo
7:45 a.m. - 2:19 p.m.
YYZ
-
SEA
9h 34m
1 stop
C$ 318Multiple Airlines
Wed, 25 Feb - Wed, 4 Mar
Air Canada Logo
8:00 a.m. - 3:43 p.m.
SEA
-
YYZ
4h 43mdirect
Air Canada Logo
8:00 a.m. - 7:16 p.m.
YYZ
-
SEA
14h 16m
2 stops
C$ 319Air Canada
Tue, 17 Mar - Tue, 7 Apr
Multiple Airlines Logo
7:55 a.m. - 3:35 p.m.
SEA
-
YYZ
4h 40mdirect
Multiple Airlines Logo
7:45 a.m. - 2:19 p.m.
YYZ
-
SEA
9h 34m
1 stop
C$ 323Multiple Airlines
Sat, 23 May - Thu, 4 Jun
WestJet Logo
7:35 p.m. - 6:55 a.m.
SEA
-
YYZ
8h 20m
1 stop
WestJet Logo
1:30 p.m. - 6:45 p.m.
YYZ
-
SEA
8h 15m
1 stop
C$ 325WestJet
Sat, 2 May - Sat, 9 May
WestJet Logo
7:35 p.m. - 5:45 a.m.
SEA
-
YYZ
7h 10m
1 stop
WestJet Logo
1:30 p.m. - 6:45 p.m.
YYZ
-
SEA
8h 15m
1 stop
C$ 327WestJet
Wed, 11 Feb - Sun, 15 Feb
United Airlines Logo
5:00 a.m. - 5:05 p.m.
SEA
-
YXU
9h 05m
2 stops
United Airlines Logo
5:10 a.m. - 10:43 p.m.
YXU
-
SEA
20h 33m
2 stops
C$ 590United 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.

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 C$ 270 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 C$ 270.

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 C$ 327, 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 C$ 364 (return) on average. On the other hand, the most expensive months are June and July, when the average cost of round-trip tickets is C$ 644 and C$ 611 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.

When flying from Seattle to Ontario, you should consider leaving on a Wednesday and avoid Saturdays if you are looking for the best rates. For your return to Seattle, you’ll find the best rates on Thursdays and the most expensive ones on Mondays.

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 a flight from Seattle to Ontario, you should book around 4 weeks before departure, which saves you about 61% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 24 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flightC$ 128
Best time to beat the crowds (8% less expensive on average)
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 travellers 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 C$ 778 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 C$ 778.

Top tips for finding cheap flights to Ontario

  • Looking for a cheap flight? 25% of our users found tickets from Seattle to the following destinations at these prices or less: Toronto C$ 111 one-way - C$ 317 round-trip

Reviews of the top 3 airlines flying 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 11810 reviews
8.5Crew
7.1Food
7.0Entertainment
8.1Boarding
7.8Comfort
Airline reviews

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.

6.0 Goodrsmrostov, Jan 2026
SEA - BOS
Read more Alaska Airlines reviews

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

From Las Vegas to Boise all went well. However, our flight was delayed in Boise and I missed my connecting flight from Seattle to Pasco. Moreover, the last flight to Pasco was full and I was booked on the 11:30 flight Sunday and given a hotel accommodation. However, I was scheduled to deliver the Sunday morning service at my church and needed to arrive no later than 10:00. Therefore, I booked a Delta flight scheduled to arrive in Pasco at 23:09. My piece of luggage checked in Las Vegas arrived in Pasco earlier today. I waited at the airport for over an hour last night to speak with an Alaska agent to no avail. I went back after church this morning in search of my piece of luggage and it could not be located. After waiting for 40 minutes to speak to the agent authorized to take my claim, he announced that he was closing the counter to assist on the flight line but not before providing me with a telephone number that would help me with filing my claim. Before I was able to make the call (due to other factors) I received a call from Alaska agent informing me that my luggage had just arrived and I am now waiting for it to be delivered. I deliberately took the more complicated route home to ensure that I would be home in plenty of time to prepare for myself for the Sunday service and accommodate my relatives’ needs. I believe the airport is undermanned given the number of flights coming in and going out. It was fiasco last night with three flights waiting for luggage and another flight landing within minutes. Today’s problems stemmed from a lack of cross training and a serious amount of cargo/baggage going out and too few people scheduled to cover.

The cabin crew was absolutely wonderful, the service was great and it was just a good flight overall.

I like them since I live in Alaska and I don't have much choice

The flight attendants were nice, but the cabin and seats were uncomfortable.

Food was terrible, noisy plane & would never pay to fly first class again. Seats in regular price are too small, no leg room & center aisle much too, too small. Seats in 1st class larger but not comfortable.

Overall, once we took off, our flight was good. Flight departure was significantly delayed due to mechanical issues. Upon arrival, it took wayyy too long to retrieve checked bags.

The ticket I purchased through Kayak did not show up in my Alaska Airlines app, and neither of the codes given to me worked for online check in. I've never had to show up to the airport at 6am wondering if I've been scammed. Cheap flight fare or whatever does not play well with airlines and I will be wary of using Kayak in the future.

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 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.

My seat was one of those that couldn't recline, but the problem was that it was abnormally upright, so the headrest actually made the seat concave, which was uncomfortable and hard on my lower back. I had to ball my jacket up and use it as lumbar support. goodness I had it with me.

I liked a lot , the flight attendant so nice ,the seat very comfortable I enjoyed the flight , I will do it again with Air Canada,

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

Information on your arrival and departure airports