Cheap flights from Ontario to Seattle (ONT - SEA)

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The best prices from Ontario to Seattle are usually found in January or February, booked 52 days in advance, depart on a Wednesday or Tuesday and return on a Wednesday

How to find the cheapest flight from
Ontario (ONT) to Seattle (SEA)

All the information you need to plan the best ONT to SEA flight in 2021: compare Ontario to Seattle flight prices with the expected peak season, weather and rainfall in Seattle.
ONT - SEA
Price
$177 - $217
SEA
Temperature
46.4 - 77 °F
SEA
Precipitation
0.7 - 6.5 inches

Popular in

November

High demand for flights, 9% potential price rise

Cheapest in

January

Best time to find cheap flights, 11% potential price drop

Round-trip from

$177

From Ontario to Seattle

One-way from

$88

One-way flight from Ontario to Seattle

Flight route prices based on searches on Cheapflights within the last 3 days, monthly prices based on aggregated historical data.
What is the cheapest day to fly round-trip from Ontario to Seattle?

Flying to your destination on a Saturday can be more expensive, but this shouldn’t discourage you from finding affordable options to get to Seattle. Check prices with Cheapflights to find a great deal for your trip.

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

Find a great deal and save up to 71% by booking at least 28 days prior to your desired departure date, rather than waiting until the week of travel. According to our data, there are a number of flights available from Ontario to Seattle within the next two weeks, with the cheapest ticket starting at $123.

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

Our data shows that April tends to be the cheapest month to fly to Seattle from Ontario. Users have commonly found prices around $115 for the month, but tickets can be as low as $36. Due to multiple factors, prepare for potentially higher prices in December.

When is the cheapest time to fly from Ontario to Seattle (ONT - SEA)?

A simple way to save on the total cost of your ticket is to fly from Ontario to Seattle at noon. If you’re flexible enough to do this you can expect to save up to 21% on your trip compared to booking a flight in the morning.

Cheap flights from Ontario to Seattle in August, September 2021

The best prices found for ONT to SEA flights for August, September
29 Aug - 13 Sep
$107pp
ONT
Ontario
Alaska Airlines
Non-Stop
SEA
Seattle/Tacoma Intl
SEA
Seattle/Tacoma Intl
Alaska Airlines
Non-Stop
ONT
Ontario
27 Aug - 27 Aug
$132pp
ONT
Ontario
Alaska Airlines
Non-Stop
SEA
Seattle/Tacoma Intl
SEA
Seattle/Tacoma Intl
Alaska Airlines
Non-Stop
ONT
Ontario
25 Aug - 30 Aug
$134pp
ONT
Ontario
Multiple Airlines
Non-Stop
SEA
Seattle/Tacoma Intl
SEA
Seattle/Tacoma Intl
Delta
Non-Stop
ONT
Ontario

Ontario to Seattle 2021 flight deals

Cheap flights to Seattle from Ontario found for this year
29 Aug - 13 Sep
$107pp
ONT
Ontario
Alaska Airlines
Non-Stop
SEA
Seattle/Tacoma Intl
SEA
Seattle/Tacoma Intl
Alaska Airlines
Non-Stop
ONT
Ontario
3 Sep - 5 Sep
$117pp
ONT
Ontario
Alaska Airlines
Non-Stop
SEA
Seattle/Tacoma Intl
SEA
Seattle/Tacoma Intl
Alaska Airlines
Non-Stop
ONT
Ontario
22 Sep - 25 Sep
$120pp
ONT
Ontario
Multiple Airlines
 
1 STOP
SEA
Seattle/Tacoma Intl
SEA
Seattle/Tacoma Intl
Multiple Airlines
 
1 STOP
ONT
Ontario

Non-stop flights to Seattle from Ontario

Save time with Ontario to Seattle direct flight deals
29 Aug - 13 Sep
$107pp
ONT
Ontario
Alaska Airlines
Non-Stop
SEA
Seattle/Tacoma Intl
SEA
Seattle/Tacoma Intl
Alaska Airlines
Non-Stop
ONT
Ontario
3 Sep - 5 Sep
$117pp
ONT
Ontario
Alaska Airlines
Non-Stop
SEA
Seattle/Tacoma Intl
SEA
Seattle/Tacoma Intl
Alaska Airlines
Non-Stop
ONT
Ontario
27 Aug - 27 Aug
$132pp
ONT
Ontario
Alaska Airlines
Non-Stop
SEA
Seattle/Tacoma Intl
SEA
Seattle/Tacoma Intl
Alaska Airlines
Non-Stop
ONT
Ontario

Last minute flights from Ontario to Seattle

Late deals on round-trip flights to Seattle from Ontario, departing today and this week
12 Aug - 15 Sep
$183pp
ONT
Ontario
Multiple Airlines
Non-Stop
SEA
Seattle/Tacoma Intl
SEA
Seattle/Tacoma Intl
Delta
Non-Stop
ONT
Ontario
12 Aug - 24 Aug
$185pp
ONT
Ontario
Multiple Airlines
Non-Stop
SEA
Seattle/Tacoma Intl
SEA
Seattle/Tacoma Intl
Alaska Airlines
Non-Stop
ONT
Ontario
12 Aug - 20 Aug
$187pp
ONT
Ontario
Alaska Airlines
Non-Stop
SEA
Seattle/Tacoma Intl
SEA
Seattle/Tacoma Intl
Alaska Airlines
Non-Stop
ONT
Ontario

One-way flights to Seattle from Ontario

The cheapest one-way flights from Ontario to Seattle
3:01 pm - 7:46 pm
Delta
1 Stop
4h 45m
ONT - SEA
Delta
$88
Delta
3:25 pm - 6:00 pm
Alaska Airlines
Nonstop
2h 35m
ONT - SEA
Alaska Airlines
1:45 pm - 6:40 pm
American Airlines
1 Stop
4h 55m
ONT - SEA
American Airlines

Related info for your journey

Useful info, stats and facts about <span class="emphasized">Ontario</span> to <span class="emphasized">Seattle</span> flights.

Flight FAQs

From Ontario to Seattle

Are flight prices decreasing from Ontario to Seattle due to COVID-19 (coronavirus)?

At this time, Cheapflights has noticed price decreases for many domestic flights due to COVID-19. Travel is not necessarily recommended at this time, and flights may be prone to cancellation: please check with local authorities in both Ontario and Seattle for travel alerts, and be sure to review the airline's cancellation policy and travel advisories before booking. For more information, please view our post on what to know about COVID-19 (coronavirus) and travel.

Which airlines flying from Ontario to Seattle/Tacoma Intl have flexible cancellations due to COVID-19?

Alaska Airlines, United Airlines, and Delta are some of the carriers that may have flexible cancellation policies. You can use our site to filter for other airlines that may also have this kind of flexibility.

What airports do I use to fly from Ontario to Seattle?

If you wish to fly to Seattle from Ontario, then you need to book flights from Ontario to Seattle/Tacoma Intl. There are 7 flights from Ontario (ONT) to Seattle/Tacoma Intl (SEA) per day to choose from. Flights to Seattle from Ontario are available from 8 different airlines, which means you should have some options if you want to compare airfare deals. 2h 30m is how long a nonstop flight from Ontario to Seattle/Tacoma Intl typically takes.

Can I find flights from Ontario to Seattle for under $200 on Cheapflights?

Yes, there are multiple flights from Ontario to Seattle for under $200. The cheapest flight booked recently is on Alaska Airlines for just $107, but on average you can expect to pay $134.

Are there nonstop flights from Ontario to Seattle for under $200 on Cheapflights?

Cheapflights has at least 20 direct flights from Ontario to Seattle under $200. A good price for a nonstop flight from Ontario to Seattle is less than $147.

Are there last-minute flights available from Ontario to Seattle for under $200?

There are currently 20+ open flights from Ontario to Seattle within the next 7 days for less than $200.

What days are nonstop flights available from Ontario to Seattle?

Nonstop flights are available for this route on the following days: Monday, Tuesday, Wednesday, Thursday, Friday, Saturday.

How popular is this flight route?

This flight path from Ontario to Seattle/Tacoma Intl was viewed by 846 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

How many flights depart from Ontario to Seattle on average per day?

On average, you can expect to see 8 flights from Ontario to Seattle/Tacoma Intl a day.
Morning (6am - Noon) - 50% of flight departures
Afternoon (Noon - 6pm) - 50% of flight departures

Does it rain more in Ontario or Seattle?

When traveling, we recommend packing in preparation to handle common weather conditions. The rainfall in Ontario is typically less than Seattle. We can gather that this will continue over the next 1 days.

Is Ontario weather warmer or cooler than Seattle?

Our data indicates that the weather will be 95 °F on average in the month of July. The temperature in Seattle is typically colder than in Ontario. If you're traveling when the temperature is at its warmest, push to plan early, as flight price and availability will have an impact on your travels. For the best results, search for flights well in advance or after peak season.

How long is the flight from Ontario to Seattle?

Departing from Ontario to Seattle will take you 2h 35m. There are 962 mi between Ontario and Seattle. Both multi-stop and nonstop flights can be found to your destination and back.

What are the cheapest airlines flying from Ontario to Seattle round-trip?

According to our current data, Alaska Airlines ($107), Frontier ($130), and Delta ($146) offers the cheapest pricing from Ontario to Seattle. These flights start at 46% lower than the current average price 3 months from now.

What are the cheapest airlines to fly from Ontario to Seattle one-way?

The cheapest airline one-way is Alaska Airlines, with whom users have recently found tickets for as low as $42. However, be on the lookout for offers from Frontier and United Airlines, as they are both options that can get you from Ontario to Seattle for a low price.

COVID Restrictions

View COVID Travel Restrictions for Seattle, WA

Do I need a COVID test to fly to Seattle from Ontario?

Information is based on travel restrictions for travel to Seattle/Tacoma Intl within the United States

Most visitors from Ontario need to provide a negative COVID-19 test result and/or quarantine to enter Seattle/Tacoma Intl.

COVID-19 testing requirements
Visitors from Ontario must present a negative RT-PCR (NAAT) or Antigen (quick-test) test taken 72 hours before departing to Seattle/Tacoma Intl.

Quarantine requirements
Visitors from Ontario are not required to quarantine after entering Seattle/Tacoma Intl.

Do I need a test to fly back to Ontario from Seattle?

Returning to Ontario from Seattle/Tacoma Intl

COVID-19 testing requirements
Visitors from Seattle/Tacoma Intl must present a negative RT-PCR (NAAT) or Antigen (quick-test) test taken 72 hours before departing to Ontario.

Quarantine requirements
Visitors from Seattle/Tacoma Intl are not required to quarantine after entering Ontario.

Hide COVID Travel Restrictions for Seattle, WA

Alternative routes for Ontario to Seattle

See prices for flight routes from nearby airports that may be better suited for you.

Destination information for Seattle

Things to know before you go - useful duration and weather info for your trip from Ontario to Seattle.
Flight duration
2h 35m
Average temperature for August in Seattle
77.0 °F
Avg rainfall for August in Seattle
1.1 ″

Airports servicing Ontario

Airports servicing Seattle

Top 7 airlines flying from Ontario to Seattle

The chart below displays the airlines Cheapflights users traveling from Ontario to Seattle choose most often. Cheapest and average prices are based on aggregated data from the past 12 months.
Airline Cheapest Average Flexibility On-time COVID-19 safety
Frontier
$106 $192 No cancel fee 62%
United Airlines
$77 $221 No cancel fee 69%
Alaska Airlines
$98 $223 No cancel fee 75%
JetBlue
$71 $225 No cancel fee 62%
Delta
$87 $226 No cancel fee N/A
Spirit Airlines
$149 $276 No cancel fee 65%
American Airlines
$94 $282 No cancel fee 71%

Hourly flight availability from Ontario to Seattle

See what time of day planes typically take off from Ontario towards Seattle.
Morning 6 AM to noon 38% of ONT to SEA departures
Early morning Midnight to 6 AM 28% of ONT to SEA departures
Afternoon Noon to 6 PM 21% of ONT to SEA departures
Evening 6 PM to midnight 13% of ONT to SEA departures
Midnight
6 AM
Noon
6 PM
Weekly flight availability
from Ontario to Seattle
See how many times per day planes take to the skies headed from Ontario to Seattle.
Sunday
8 daily flights
Monday
8 daily flights
Tuesday
7 daily flights
Wednesday
7 daily flights
Thursday
7 daily flights
Friday
7 daily flights
Saturday
7 daily flights
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