$70 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 10/10. 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

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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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Cheap Flights from Seattle to Ontario

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Toronto
Hamilton1 stop$205
Ottawa
Ottawa1 stop$261
Thunder Bay
Thunder Bay2 stops$419
London
London2 stops$742
Toronto
Hamilton1 stop$205
Ottawa
Ottawa1 stop$261
Thunder Bay
Thunder Bay2 stops$419
London
London2 stops$742

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

週三, 9月 17 - 週二, 9月 23
WestJet Logo
1:50 pm - 12:40 amSEA-YHM
7h 50m1 stop
WestJet Logo
6:00 am - 12:59 pmYHM-SEA
9h 59m1 stop
$205WestJet
Find Deal
週五, 9月 5 - 週一, 9月 8
WestJet Logo
1:50 pm - 12:40 amSEA-YHM
7h 50m1 stop
WestJet Logo
6:00 am - 12:59 pmYHM-SEA
9h 59m1 stop
$207WestJet
Find Deal
週五, 9月 5 - 週日, 9月 7
WestJet Logo
1:15 pm - 12:31 amSEA-YYZ
8h 16m1 stop
WestJet Logo
6:45 am - 12:35 pmYYZ-SEA
8h 50m1 stop
$211WestJet
Find Deal
週五, 9月 19 - 週日, 9月 21
WestJet Logo
1:15 pm - 12:31 amSEA-YYZ
8h 16m1 stop
WestJet Logo
9:00 am - 7:14 pmYYZ-SEA
13h 14m2 stops
$212WestJet
Find Deal
週五, 9月 5 - 週三, 9月 17
WestJet Logo
1:15 pm - 12:31 amSEA-YYZ
8h 16m1 stop
WestJet Logo
12:00 pm - 8:29 pmYYZ-SEA
11h 29m2 stops
$217WestJet
Find Deal
週六, 9月 13 - 週日, 9月 21
 Logo
2:55 pm - 5:30 amSEA-YKF
11h 35m2 stops
 Logo
6:15 am - 6:36 pmYKF-SEA
15h 21m2 stops
週四, 9月 18 - 週四, 9月 25
Air Canada Logo
5:30 am - 8:41 pmSEA-YTZ
12h 11m2 stops
Air Canada Logo
12:25 pm - 7:31 pmYTZ-SEA
10h 06m1 stop
$273Air Canada
Find Deal
週四, 9月 18 - 週四, 9月 25
Air Canada Logo
5:30 am - 8:41 pmSEA-YTZ
12h 11m2 stops
Air Canada Logo
12:25 pm - 7:31 pmYTZ-SEA
10h 06m1 stop
$276Air Canada
Find Deal
週四, 9月 18 - 週四, 9月 25
Air Canada Logo
5:30 am - 8:41 pmSEA-YTZ
12h 11m2 stops
Air Canada Logo
4:10 pm - 10:16 pmYTZ-SEA
9h 06m2 stops
$293Air Canada
Find Deal
週六, 9月 13 - 週日, 9月 21
Air Canada Logo
5:30 am - 6:45 pmSEA-YTZ
10h 15m2 stops
Air Canada Logo
4:10 pm - 10:16 pmYTZ-SEA
9h 06m2 stops
$294Air Canada
Find Deal
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 $305 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 $305.

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.

Yes, flying with a layover may cost you more time, but you can also save money on the route, with a 2 stops layover the cheapest option at $784 on average.

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 $283 (return) on average. On the other hand, the most expensive months are June and July, when the average cost of round-trip tickets is $498 and $497 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 4 weeks before departure, which saves you about 53% 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 flight$70
Best time to beat the crowds with an average 14% drop in price.
Most popular time to fly with an average 1% increase in price.
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 evening, when round-trip flights cost $283 on average. Morning departures are around 122% more expensive than evening flights, 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 $628.

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 10000 reviews
7.1Entertainment
8.5Crew
7.1Food
7.8Comfort
8.1Boarding
Airline reviews

Arrived in Seattle to find our non stop flight was canceled and that we were rebooked to depart 16 hrs later. We stood in customer relation line for well over an hour and a half to find out what to do with our frozen fish that was checked bags and to get to our destination in a more timely fashion. There were only 2 Alaska reps working trying to help at least 2 cancelled flights that we know about. At one point a 3 rd rep showed up and shortly after one rep left stating she was going on break. There were atleast 50 people still in line. Finally We were rerouted through a different airport adding another stop the next day and given flight confirmation but no seat assignment stating ticket vouchers needed to be attached. We were then told to go to Alaska air luggage to request our fish be put in the freezer. The supervisor at baggage told us the freezer was full and that there was nothing he could do about it. Luckily he walked off and the ladies at the counter made sure our fish was put in the freezer. The following morning we had to be back to baggage to make sure our fish was tagged appropriately to get to our destination on a separate flight. . Both of our return flights we had to take we had to stand in line for the ticket people to try to find our ticket vouchers to attach to the boarding passes we were given. Al together our return took 31 hrs instead of the 12 hrs scheduled.

2.0 MediocreJason, Aug 2025SEA - RNO
Read more Alaska Airlines reviews

Arrived in Seattle to find our non stop flight was canceled and that we were rebooked to depart 16 hrs later. We stood in customer relation line for well over an hour and a half to find out what to do with our frozen fish that was checked bags and to get to our destination in a more timely fashion. There were only 2 Alaska reps working trying to help at least 2 cancelled flights that we know about. At one point a 3 rd rep showed up and shortly after one rep left stating she was going on break. There were atleast 50 people still in line. Finally We were rerouted through a different airport adding another stop the next day and given flight confirmation but no seat assignment stating ticket vouchers needed to be attached. We were then told to go to Alaska air luggage to request our fish be put in the freezer. The supervisor at baggage told us the freezer was full and that there was nothing he could do about it. Luckily he walked off and the ladies at the counter made sure our fish was put in the freezer. The following morning we had to be back to baggage to make sure our fish was tagged appropriately to get to our destination on a separate flight. . Both of our return flights we had to take we had to stand in line for the ticket people to try to find our ticket vouchers to attach to the boarding passes we were given. Al together our return took 31 hrs instead of the 12 hrs scheduled.

Better could be service of your checking staff on the gait N15 at Seattle Tacoma airport... Flight AS 378 , 08/02/2025. Time 9.45 AM. I was very disappointed of their job.

My 1.5 hr flight was 5.5 hrs delayed. We switched gates twice. We planed and deplaned once. Three total planes, two had “mechanical issues.” None of this even makes sense as the original plane was sitting at the gate since yesterday evening. Then when the second plane was finally brought to the gate from the hangar, it too needed repair. Don’t worry. They gave us a $12 foot voucher. All other flights in the same area of the terminal were hours delayed. It was an actual nightmare. This was after a few hours delay on my first flight a few days ago. And I thought that was bad.

Terrible. Would never fly again. Took them several hours to prepare the plane and and reached my destination 4 hours late.

Our boarding was delayed due to two flat tires, but I appreciate the focus on safety. I also appreciated the additional offerings for drinks which never happened before except on Hawaiian Airlines. The hospitality is fantastic! Glad I upgraded to premium seats for the extra leg room as I was getting frustrated when the person in front of me was very restless and kept shifting. Otherwise, it was a fantastic experience.

More leg room would be nice. Especially for older people

We flew to Seattle on 7/21, right after the company wide problems the day before. We were delayed 3 hours but understood. We were grateful it wasn’t canceled. As a larger, disabled person, my son booked us in 1st class, row 1. That was fine. My problem occurred while trying to use the restroom. I had to back in and barely had room to move. I started into a silent panic attack where my breathing was affected. I made it back to my seat, shaken. I understand space is limited but something needs to be done. This was on the trip out. The return trip had 4-5 disabled passengers. I watched them struggle. This plane’s restroom was a “little “ bigger. It was a little easier compared to the first plane. That’s my opinion! The crews were fantastic on both flights!

I was in the middle seat in the last row but that wasn’t their fault. It is why I rated the flight as mediocre, also the landing was a little rough. The good was really good. The self service luggage belt at SEATAC stopped working right when I reached it. I was literally placing my bag on the small belt when the main belt stopped. I understand that it wasn’t just Alaska but the entire side of the terminal. It took the agents about 20 minutes to arrive at a game plan and it certainly wasn’t flawless but they arranged for our luggage to be taken to the plane the old fashioned way by hand. Understandably, the plane was late in leaving. The flight took the proper amount of time and instead of arriving at OAK at 1:45, we got there at 2:30. I took my time getting to baggage claim because I knew it would be late if it was there at all. Sure enough it wasn’t but there was an agent there to greet me and inform me about my luggage. Long story longer, they delivered my luggage to where I was staying which was an hour away from the airport. Alaska has instituted a delivery type tracking system through my email that kept me informed of where my luggage was the whole time. WELL DONE!!

Crew was very friendly. Our bags showed up at the carousel within 20 minutes of arrival.

Flight was delayed and hour due to tire issue. First flight of the day, this issue should have been discovered prior to boarding.

Having to up charge for a seat assignment is not good. Delta can do better

I liked the friendliness of the staff. The cleanliness of all 3 planes.

Was charged for my luggage despite having been on one ticket from an international flight. Too tired to argue after 15 hours on flight. Was charged for rechecking it at JFK airport. Not sure why those off Kenya Airways were required to do that.

De planning was an absolute mess. We were never told that we weren’t at the gate and that we had to go down unstable stairs and then hop on a bus. People were falling, we couldn’t tell who was in charge. Overall terrible communication that ended up leaving a bad impression at the very end of the experience.

My experience on any Delta flight is always overshadowed by the time Delta removed me from a flight for no apparent reason.

Delayed and took off even later than the scheduled delay time

For a 69 year old with health problems I had the worse experience, no wheelchair when I entered a lady told me to sit and wait while a gentleman told me I had to walk to the Delta station, which I did. I had a carry on and a bag, and I was traveling with my service dog, which was on his carrier and the lady charged me for my carry on luggage, beside all the waiting cause of the delay, I had to walk to get my luggage cause no wheelchair showed up, I am so disappointed. I will get in touch with the company. I got home at 3:00 am, not good for my health situation.

Only issue was with seating. The economy fare we purchased did say there was no guarantee the three people in our party would be seated together, and we were not. At the gate, the agent told us more specifically, the fare we purchased meant we would be seated in middle seats only. This should just be made more obvious.

Great experience on Delta. Staff from baggage check to flight attendants were very courteous and professional. My only issue was a personal preference for pretzels instead of the chips and cookies that were offered.

There was no problems, just a little uncomfortable with seats that do not lay back a little

the delay for 3 hours was understandable due to weather conditions but the flight should’ve provided some on flight compensations or at least provide more food.

Flight was actually on Air Canada. The flight itself was fine. Nothing special. Food was pretty pathetic except for cookies. They offered plenty of food and drinks but just wasn't very good. Even for airline food.

Boarding experience was smooth. Flight attendants were friendly and helpful. Entertainment system on the Houston-Edmonton flight did not function for passengers on the left side of the aisle. On the bird's eye flight from Quito to Houston, they should not serve a meal. No one needs to eat after midnight and it is disturbing for those passengers trying to sleep.

Flight was late as pilot crew had to land at different airport in their previous flight. Passengers boarded and had to wait for pilots inside plane. Series of incomplete and unnecessary announcements by an annoying voice, rather than complete, informative announcements.

Delay and keep changing gates. I have to run around from B to C then to E.

Boarding was a little difficult. The gate area at O'Hare was very small and crowded due to multiple gates in the area. Could not hear the intercom, so had to rely on signage to see when my group was boarding and the signage was blocked by passengers standing in the gate. Flight was great and we arrived in Montreal on time.

My suitcase was completed destroyed. The top part is broken and unusable now.

When I booked it on Kayak it aaid that I wasn't allowed hamd luggage. I called United Airlines and it took them 6 minutes to figure out if I was allowed free hand luggage. Surely something that simple they should be able to tell me instantly.

I do prefer to fly United and have always had excellent service, except for bad weather. Flights are on time and staff is alway curtious and helpful

We were delayed in Toronto on the tarmac for THREE hours with no clear indication as to why except that it was not a safety hazard. Pilot did apologize more than once but even he was unable to explain why exactly we were delayed. I overheard the stewards saying that the captain was very frustrated with the situation as well because he was not able to explain why except it had something to do with water supply or system on the aircraft and now we needed to wait for an engineer to approve the aircraft for flight. It was very frustrating and distressing as a passenger and we should have been given complimentary meals at the very least.

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 flight attendants were super! They created a cosy and warm flight atmosphere!

West Jet flight was cancelled and I was not notified. I found out when I tried to check in on-line. Spent 4 hours on the phone with West Jet and Just Fly trying to figure what happened.

It was good, flight was on time, boarding was smooth and done in zones, food was good too but there was no form of entertainment. Luggage’s were intact. So an overall good flight

Flight was delayed 3 times. Then cancelled due to pilot being timed out. They refused hotel vouchers. Gate attendants were very rude and could not help you at all.

No access to any entertainment No food other than a cookie or pretzels even tho flight was over the supper hour Seats very close together and very little leg room Staff was very good

The cancelation of my flight from Toronto to Edmonton without any solution given to me for my next flight. Very poor connection from Toronto to Edmonton

Too squished in seats. I'm 110 lbs and 5'6....can't imagine being any bigger and flying

They could care less about you. Just under a 4 hour delay in Seattle, leading into a missed connection in Vancouver, which led to 2 more delays that added up to 3 more hours leaving us to have to sleep on the floor of the Toronto airport cause they don't help you find accomodations and they just book you on the next flight out. Took an additional 14 hours to get home. Always given the brush off to get rid of us. Worst airline ever

I booked my flight months ago, and checked-in online about 12 hours before the flight. I received an email confirmation of check-in. I had no subsequent communication from Air Canada after my original booking. After arriving at the airport three hours before the flight, as instructed, I waited 90 minutes for an agent to appear to check my bag. I was informed that my flight had been canceled many weeks before, and that flight was no longer being run!! I showed a copy of my check-in confirmation, but no explanation could be found. I was placed on standby for the next flight and the connection. Luckily, those flights were not full and I arrived at my destination. I double checked my email, but I received no update about the flight from Air Canada until the day of the flight.

I was forcefully re-routed to another destination and was delayed a total of 8hours. I have still not received my bags, no one is taking responsibility. The agents at the airport lied to me that I will get to my destination same time as my previous flight where I was forcefully re-routed from.

Flight was delayed by 1.5hrs. Once inside, people had their small handbags on the storage. The crew (male guy) was not helpful in making some space in the storage. Instead, he asked few bags to be checked-in and it was not a great experience. No attempt to help but just followed the things with a straight face. People had their literally small bags and he wouldnt not move from one storage to another even if there was space and would not let us do i as well. Once flight was on, they ran out of Orange juice, really running out of orange juice when the temp were 32.degrees outside. didnt made the sense. Onasking for a extra snack, he made a face as if he was giving me out of his pocket. if the flight was delayed, there could have an attempt to provide something extra incase people did asked.

Our flight was canceled at the last minute. Someone on the flight said the exact same thing happened to her the day before. I will say they helped us book a flight on another airline so that we could still make our vacation with little delay.

We had a very long delay. First the inbound flight took a while, then maintenance, they “fixed it” to then do boarding and leave the gate, and waste a lot of time to have to go back to the gate and eventually deplane. Had to wait for a new aircraft, wait for a gate, and do the whole thing again. Instead of leaving at 9:50am we left until past 1. I could’ve not woken up at 5am, or spend some more time with my family if they gave more grace period of time between flights to give some time in case of any issues. But they have to make all and every dollar possible

Abandoned me in hallway in a wheelchair… which I asked for because I sprained my back. After waiting in the hallway, I decided to walk the rest of the way since someone respecting me up.. My experience with the united was totally the opposite. Wheelchair access, propped swift and save me a lot of grief. Air Canada totally disorganized.

Bad experience boarding and flight got delayed didn’t make it to my next flight

The food on the trip Toronto to Athens could be better: the chicken didn’t taste good.

Conflicting information provided about baggage allowance. One screen said I had a carry on and another said I didnt.

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

Information on your arrival and departure airports

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