Cheap flights from Ontario to Seattle from $211
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Ontario to Seattle departing on 11/22. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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Fly from
Fly to
Route
Depart
Return
TorontoSeattle
YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl
YYZSEA
Toronto Pearson Intl
Wed 11/25
7:30 am-1:40 pm
1 stop9h 10m
Seattle/Tacoma Intl
Mon 11/30
2:30 pm-5:45 am
2 stops12h 15m
TorontoSeattle
YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl
YYZSEA
Toronto Pearson Intl
Fri 11/20
7:30 am-1:40 pm
1 stop9h 10m
Seattle/Tacoma Intl
Wed 12/2
2:30 pm-5:45 am
2 stops12h 15m
TorontoSeattle
YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl
YYZSEA
Toronto Pearson Intl
Fri 1/8
7:30 am-1:40 pm
1 stop9h 10m
Seattle/Tacoma Intl
Mon 1/18
10:09 am-6:50 am
1 stop17h 41m
TorontoSeattle
YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl
YYZSEA
Toronto Pearson Intl
Sat 11/7
12:10 pm-6:35 pm
1 stop9h 25m
Seattle/Tacoma Intl
Sat 11/14
11:40 pm-11:09 am
1 stop8h 29m
TorontoSeattle
YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl
YYZSEA
Toronto Pearson Intl
Sat 11/7
6:00 am-3:21 pm
1 stop12h 21m
Seattle/Tacoma Intl
Wed 11/11
9:45 am-10:57 pm
1 stop10h 12m
TorontoSeattle
YYZ Toronto Pearson Intl - SEA Seattle/Tacoma Intl
YYZSEA
Toronto Pearson Intl
Tue 11/10
6:00 am-2:50 pm
1 stop11h 50m
Seattle/Tacoma Intl
Wed 11/11
10:40 pm-11:09 am
1 stop9h 29m
OttawaSeattle
YOW Ottawa - SEA Seattle/Tacoma Intl
YOWSEA
Ottawa
Thu 12/3
7:45 am-2:37 pm
1 stop9h 52m
Seattle/Tacoma Intl
Tue 12/8
7:45 am-6:45 pm
1 stop8h 00m
OttawaSeattle
YOW Ottawa - SEA Seattle/Tacoma Intl
YOWSEA
Ottawa
Tue 11/17
7:45 am-2:32 pm
1 stop9h 47m
Seattle/Tacoma Intl
Tue 12/1
7:45 am-6:45 pm
1 stop8h 00m
OttawaSeattle
YOW Ottawa - SEA Seattle/Tacoma Intl
YOWSEA
Ottawa
Mon 12/7
3:10 pm-9:46 am
2 stops21h 36m
Seattle/Tacoma Intl
Fri 12/11
2:30 pm-3:07 pm
2 stops21h 37m
OttawaSeattle
YOW Ottawa - SEA Seattle/Tacoma Intl
YOWSEA
Ottawa
Thu 11/5
6:15 am-7:03 pm
1 stop15h 48m
Seattle/Tacoma Intl
Sun 11/15
10:56 pm-2:09 pm
1 stop12h 13m
See travel insights to Seattle from
How to get the cheapest flight ticket from Region of Ontario to Seattle
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the cheapest month to fly to Seattle?
In general, February is the cheapest month to fly from Region of Ontario to Seattle. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $249. If you don’t want to visit Seattle in February, then you should wait until January to fly from Region of Ontario, when ticket prices are also cheap, with an average price of $276.
What is the cheapest day to depart on your flight to Seattle?
On average, the least expensive day to fly to Seattle from Region of Ontario is on a Friday. momondo users have found tickets for Friday departures for as low as $481. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Monday is the most expensive day to depart from Region of Ontario because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $804.
What is the cheapest time of day to depart on your flight to Seattle?
Flying to Seattle from Region of Ontario in the evening is the least expensive time of day to depart. momondo users have found prices as low as $468 when looking at flights departing in the evening. Flights to Seattle are more costly in the morning, with an average ticket price of $694. Departure times in the morning fall within the peak daily travel times, which is why tickets can be more expensive.
What is the cheapest Ontario to Seattle/Tacoma Intl flight route?
Fly from Toronto Pearson Intl to Seattle/Tacoma Intl for the best Ontario - Seattle/Tacoma Intl flight prices
How far in advance should I book a flight from Ontario to Seattle?
You are more likely to see cheaper flights to Seattle from Region of Ontario when booking weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around $384 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from Region of Ontario for as low as $303 on momondo.
What cabin class options are available on Region of Ontario to Seattle flights?
There are 4 cabin classes available to choose from on Region of Ontario to Seattle flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
What is the cheapest airline that flies from Ontario to Seattle/Tacoma Intl?
WestJet, Delta, and Air Canada are the most popular carriers operating from Ontario to Seattle/Tacoma Intl
What airlines fly to Seattle?
Air Canada, Alaska Airlines and WestJet are the top three most popular airlines that fly to Seattle from Region of Ontario according to our data. Air Canada is the first choice among our users, with 36% of people opting to fly with this airline when traveling to Seattle. Keep in mind that there are 5 different airlines that fly to Seattle on a routine basis, so you have a few additional options to choose from.
How many flights depart from Region of Ontario to Seattle on average per day?
As of October 2026, 2 flights take off from Region of Ontario and land in Seattle each day. The most common flight departure time for this route is 6:00PM, with 85% of daily flights taking off in the evening.
How many flights depart from Region of Ontario to Seattle on average per week?
The number of flights available between Region of Ontario and Seattle is 14 per week as of October 2026. The most frequent departure day is Fri, with 21% of weekly flights leaving on this day.
Cheap Region of Ontario to Seattle flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Region of Ontario to Seattle
Frequently asked questions about flying from Ontario to Seattle
When did momondo last update prices for flights from Ontario to Seattle/Tacoma Intl Airport?
Prices for flights from Ontario to Seattle/Tacoma Intl Airport refresh daily.
How many operators does momondo search for flights from Ontario to Seattle/Tacoma Intl Airport?
The number of operators available for flights from Ontario to Seattle/Tacoma Intl Airport is 5 as of October 2026.
How old do you have to be to fly from Ontario to Seattle/Tacoma Intl Airport?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Ontario to Seattle/Tacoma Intl Airport.
What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?
The travel and health documents required for your trip to Seattle/Tacoma Intl Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Seattle/Tacoma Intl Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular plane model from Region of Ontario to Seattle?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from Region of Ontario to Seattle is Boeing 737 MAX 9 (33.76% of total bookings). The next most popular plane models are Airbus A220-300 (20.38%), Boeing 777-300ER (8.92%), and Boeing 737 MAX 8 (8.28%).
Best airlines flying from Region of Ontario to Seattle
Compare and see reviews for airlines that fly from Region of Ontario to Seattle with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $202 | Free Cancellation | Rating 7.9 13,041 reviews | |||
| PriceFrom $206 | Free Cancellation | Rating 7.1 11,750 reviews | |||
| PriceFrom $209 | Free Cancellation | Rating 7.8 8,654 reviews | |||
| PriceFrom $213 | Free Cancellation | Rating 7.2 3,452 reviews | |||
| PriceFrom $219 | Free Cancellation | Rating 7.4 10,332 reviews |
Traveling to a place near Seattle?
Book flights to Seattle if you plan to visit one of these locationsWhy use momondo?
Why should I use momondo to find a flight deal from Ontario to Seattle?
Finding the right flight to Seattle from Ontario is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to Seattle quick and easy, saving you time and money.
Can I find flights from Ontario to Seattle with flexible booking policies on momondo?
momondo does allow users to show only those flights to Seattle from Ontario which offer a flexible booking policy as well as other useful filters and features.
How can momondo help me find flights from Ontario to Seattle?
Once you have performed a search for Ontario to Seattle flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.
I’m not ready to book a flight from Ontario to Seattle right now. Can momondo alert me if prices change?
If you are simply researching potential flights to Seattle, momondo offers a useful price alert feature which will track prices for flights to Seattle from Ontario and alert you when they change.