C$ 220 Find Cheap Flights from Seattle to Ontario – Compare and Save

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 6/9. 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
Travellers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

Save 20% or moreCompare multiple travel sites with one search.

Track pricesNot ready to book? Create a price alert for when prices drop.

Free to useThere are no hidden charges or fees.

Filter your dealsChoose cabin class, free Wi-Fi and more.

Flight Deals
Booking Insights
Flight Deals

Best Ontario Flight Deals from Seattle

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Toronto
Toronto1 stopC$ 516
Ottawa
Ottawa1 stopC$ 562
London
London1 stopC$ 617
Toronto
Toronto1 stopC$ 516
Ottawa
Ottawa1 stopC$ 562
London
London1 stopC$ 617

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

Thu, 2 Jul - Tue, 14 Jul
WestJet Logo
7:00 a.m. - 5:10 p.m.
SEA
-
YYZ
7h 10m
1 stop
WestJet Logo
1:30 p.m. - 6:45 p.m.
YYZ
-
SEA
8h 15m
1 stop
C$ 516WestJet
Wed, 9 Sep - Wed, 18 Nov
WestJet Logo
7:35 p.m. - 5:45 a.m.
SEA
-
YYZ
7h 10m
1 stop
WestJet Logo
7:45 a.m. - 1:20 p.m.
YYZ
-
SEA
8h 35m
1 stop
C$ 517WestJet
Tue, 7 Jul - Tue, 14 Jul
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$ 521WestJet
Thu, 2 Jul - Thu, 9 Jul
WestJet Logo
7:00 a.m. - 9:10 p.m.
SEA
-
YYZ
11h 10m
2 stops
WestJet Logo
3:50 p.m. - 9:00 p.m.
YYZ
-
SEA
8h 10m
1 stop
C$ 523WestJet
Wed, 9 Sep - Wed, 18 Nov
Multiple Airlines Logo
5:40 a.m. - 7:13 p.m.
SEA
-
YYZ
10h 33m
2 stops
Multiple Airlines Logo
7:45 a.m. - 1:20 p.m.
YYZ
-
SEA
8h 35m
1 stop
C$ 524Multiple Airlines
Wed, 1 Jul - Thu, 9 Jul
WestJet Logo
10:30 a.m. - 10:45 p.m.
SEA
-
YYZ
9h 15m
1 stop
WestJet Logo
12:00 p.m. - 6:45 p.m.
YYZ
-
SEA
9h 45m
2 stops
C$ 527WestJet
Wed, 9 Sep - Wed, 18 Nov
Multiple Airlines Logo
10:30 a.m. - 9:15 p.m.
SEA
-
YYZ
7h 45m
1 stop
Multiple Airlines Logo
6:25 p.m. - 8:54 p.m.
YYZ
-
SEA
5h 29mdirect
C$ 532Multiple Airlines
Mon, 13 Jul - Tue, 21 Jul
Air Canada Logo
3:00 p.m. - 7:10 a.m.
SEA
-
YUL
13h 10m
2 stops
Air Canada Logo
10:40 a.m. - 9:07 p.m.
YUL
-
SEA
13h 27m
2 stops
C$ 566Air Canada
Fri, 28 Aug - Tue, 1 Sep
United Airlines Logo
11:00 p.m. - 10:06 a.m.
SEA
-
YTZ
8h 06m
1 stop
United Airlines Logo
7:20 p.m. - 9:36 a.m.
YTZ
-
SEA
17h 16m
1 stop
C$ 679United Airlines
Fri, 3 Jul - Fri, 10 Jul
Air Canada Logo
7:20 p.m. - 7:45 a.m.
SEA
-
YTZ
9h 25m
2 stops
Air Canada Logo
8:55 p.m. - 10:07 a.m.
YTZ
-
SEA
16h 12m
2 stops
C$ 719Air Canada
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 July.

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 5 days was to Toronto, at C$ 439 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 5 days was C$ 439.

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

The average price for all round-trip flights from Seattle to Ontario depending on the time of departure, clicked by users on KAYAK in the last 2 weeks.

The cheapest time of day to fly to Ontario is generally in the morning, when round-trip flights cost C$ 867 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$ 867.

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 C$ 396 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 November, when tickets cost C$ 123 (return) on average. On the other hand, the most expensive months are May and August, when the average cost of round-trip tickets is C$ 222 and C$ 213 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 Thursday and avoid Mondays 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 3 weeks before departure, which saves you about 51% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 14 weeks before departure.

Good to know

Low seasonMarch
Cheapest flightC$ 220
Best time to beat the crowds (32% less expensive on average)
Most popular time to fly (15% more expensive 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.

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$ 339 one-way - C$ 893 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.
7.9
Alaska AirlinesOverall score based on 12482 reviews
8.5Crew
7.0Entertainment
7.8Comfort
7.0Food
8.1Boarding
Airline reviews

A five hour nonstop flight traveling over a few time zones and over the dinner hour and you get a small bag of pretzels. And no screens to watch movies. I

4.0 OkayDean, Jun 2026
SEA - DCA
Read more Alaska Airlines reviews

A five hour nonstop flight traveling over a few time zones and over the dinner hour and you get a small bag of pretzels. And no screens to watch movies. I

The flight kept getting delayed due to a maintenance issue. That happens, but there is no excuse for changing the gate FIVE TIMES, including one time nearly all the way across SeaTac. After we were delayed for 3+ hours, they did send us (via email) a $12 meal voucher...except you can't find a $12 meal anywhere in that airport, unless you consider a bag of M&M's and a bottle of water a meal. The plane had one problem after another but finally took off 4.5 hours late. This caused us to miss our hotel shuttle at ORD (they didn't run past midnight and it was 3 am) so we had to wait 25 minutes and pay for an Uber. I did get a $50 flight voucher from Alaska...big deal. Barely covers my Uber ride that I shouldn't have needed.

I upgraded to a better seat and it was much more comfortable. Nobody serves food anymore and actually on a 2+ hr flight not necessary. I didn’t even get water.

Check in & bag drop was straightforward. Alaskair changed the gate approx 40 min before departure, and I only became aware due to Google wallet update to my boarding pass. Had to move from gate N1 to C9 which required use of the Train, luckily I had time available.

Very short leg - too short for any meals/snacks or entertainment.

Super impressed by staff courtesy, and assistance, Flight was one of the best I've had despite turbulence... Will definitely be flying Alaskan air as my preferred choice

My boarding passes were pulled from my Apple wallet and my 3 family members who were all sitting together in the same row all got put middle seats and were one of the last to board and barely were able to get our bags in the luggage bins.

Was disappointed not to have known Alaska Air offers no music, no flight aware, no films.

I was surprised by everything. The cleanliness, the punctuality, the friendliness of the crew… and the Wi-Fi! Please keep up the good work.

The flight attendant and first class were very friendly, efficient, and wanted to make sure that service was great. Highly recommend this airline.

Westjet never disappoint always terrible small plane ,crowded cheap snack if you can call it snack

Westjet was late and we missed our connecting flight with Cathay. Had to wait 8 hours. Westjet only allows 1 checked in baggage for international flights- it’s always been 2. Canada allows only 1 sandwhich bag size full off small liquids. Everything else will be tossed. Awful trip. Will never fly west jet or go to Toronto to connect flights!

I didn’t have any food but my Prosecco hit the spot. We left on time and the crew was friendly.

I thought the coffee was excellent! The wait for the luggage was acceptable.. It left and arrived on time. My son found that his device worked very well and he really enjoyed his flight! The stewardess moved him up to the emergency exit and he very much appreciated that!

I wasn’t able to book or pay for a seat and they forgot to check me in for my third flight so I spent 24 hours in Toronto waiting for another one.

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

It was a short flight so, everything went smoothly and we got to where we needed to be safely.

No TV on the flight. The charging outlet was not working. No food, even a sandwich. The served orange was poor quality.

Selected seats 5 months prior to date. Had email confirmation and seats were not honoured. Family did not sit together

They did not let us board because one member needed a transit visa, which was not evident at the time of ticket purchase.

I was charge a baggage checking fee $68!! I volunteered to check my duffle bag which usually goes under my seat!

I did not like anything because the flight was cancelled yesterday and I did not get to arrive on time in Toronto as I was rebooked with another airline. This caused me to be really stressed out as I am an individual with back injury and to be forced to stay longer in an airport to accommodate a change of airline and the transfers associated with it Due to this I am probably not going to book through your website to eliminate this potentially chaos in the future

shittiest airline in the hemisphere. To improve - start thinking you're flying people, not cattle

Easy boarding, inflight refreshments came on time and comfortable seat

It was good that our flight left early. It was a nice smooth flight and landing.

All good……but luggage didn’t make it on the airplane. Had to wait 3 days. Was a bummer.

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

Information on your arrival and departure airports