Cheap Flight Tickets from Ontario (ONT) to Seattle (SEA), Starting at $222

Good to Know: Cheapest and Fastest ONT - SEA Flights

Useful information for finding best airline tickets from Ontario International to Seattle Tacoma International on your next trip.

Cheapest Round Trip Flight

$227

WN Southwest Airlines • 1 stop • 10h 40m

Aug 09 – Aug 16

The cheapest round trip flight from Ontario to Seattle (ONT-SEA-ONT) is currently $227

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Cheapest One way Flight

$323

WN Southwest Airlines • 1 stop • 8h 20m

Aug 11

The cheapest one way flight from Ontario to Seattle (ONT-SEA) is currently $323

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Cheapest Direct Flight

$222

F9 Frontier Airlines • nonstop • 4h 9m

Aug 09

The cheapest nonstop flight from Ontario to Seattle (ONT-SEA) is currently $222

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Fastest Flight

3h 59m

The fastest nonstop flight from Ontario to Seattle (ONT-SEA) takes 3h 59m

Top Airlines Flying from Ontario to Seattle

Southwest Airlines-WN

Southwest Airlines

Delta Airline, DL

Delta Airlines

Alaska Airlines -AS

Alaska Airlines

United Airlines, UA

United Airlines

American Airlines, AA

American Airlines

Aeromexico Airline (AM)

Aeromexico

Latest Flight Deals from Ontario (ONT) to Seattle (SEA)

Compare and book low fare round-trip air tickets from Ontario to Seattle. Ideal for travelers with confirmed return itineraries.

Aug 09 - Aug 16, Economy
WN
Ontario → Seattle
10h 40m
6:10 PM - 12:50 AM • 1 stop
WN
Ontario → Seattle
10h
7:10 AM - 1:10 PM • 1 stop
$227
Southwest Airlines
Aug 09 - Aug 16, Economy
WN
Ontario → Seattle
17h
2:30 PM - 12:50 AM • 1 stop
WN
Ontario → Seattle
10h
7:10 AM - 1:10 PM • 1 stop
$227
Southwest Airlines
Aug 09 - Aug 16, Economy
AS
Ontario → Seattle
4h 9m
9:20 PM - 11:59 PM • nonstop
F9
Ontario → Seattle
4h 15m
8:53 PM - 8:03 AM • 1 stop
$502
Alaska Airlines
Aug 09 - Aug 16, Economy
DL
Ontario → Seattle
14h 19m
1:06 PM - 10:05 PM • 1 stop
DL
Ontario → Seattle
4h 14m
8:22 AM - 11:16 AM • nonstop
$746
Delta Airlines
Aug 09 - Aug 16, Economy
DL
Ontario → Seattle
42h 24m
1:06 PM - 2:50 PM • 1 stop
DL
Ontario → Seattle
4h 14m
8:22 AM - 11:16 AM • nonstop
$746
Delta Airlines
Aug 09 - Aug 16, Economy
DL
Ontario → Seattle
8h 20m
5:05 PM - 10:05 PM • 1 stop
DL
Ontario → Seattle
45h 7m
5:45 AM - 8:52 AM • 1 stop
$765
Delta Airlines

Fly from Ontario to Seattle with the Best Airfare Deals on FareLeaders

Looking for a cheap last-minute deal or the best round-trip flight from Ontario to Seattle? Find the biggest savings on one-way and round-trip tickets right here.

FAQs on Ontario to Seattle Flights

What are the airports in Ontario?
ONT
What’s the most popular airline flying from ONT to SEA?
The most popular airline flying from Ontario to Seattle are
Can I fly from ONT to SEA non-stop?
Yes, you can fly ONT to SEA non-stop on
Which airlines fly nonstop between Ontario and Seattle?
The non-stop flights between Ontario and Seattle are .
What’s the earliest departure time from ONT to SEA Airport?
The earliest flight leaves ONT at 6:00 am and lands in SEA - Seattle Tacoma International
What are the airports in Seattle?
SEA
Can I make changes to my Ontario to Seattle flight tickets or cancel them on FareLeaders.com?
No. We are an airfare comparison site. All the tickets are booked by the travel agent offering the flight deal and any changes or cancellations to be made are directly done directly by them or the airlines.
Can I cancel my flight tickets from ONT to SEA?
Read the fare rules of the Ontario to Seattle air tickets booked. Some airlines allow you to cancel the tickets within a stipulated time period with a cancellation fee.
Which airline alliances offer flights from Ontario and Seattle?
operate flights between Ontario and Seattle
How long does a flight from Ontario to Seattle take?
It takes approximately 3 hour to fly non-stop from ONT to SEA, which is 956.13 miles by air.
Which airlines provide the cheapest flights from Ontario (ONT) to Seattle (SEA) ?
In the past couple of days, the cheapest tickets to SEA from ONT were found on DL : USD 353
Do I need a passport to fly between ONT and SEA?
No
What’s the latest departure time from ONT to SEA ?
The last flight leaves ONT at 9:20 pm

Essential Information for Booking Flights from Ontario (ONT) - AI Insights

What's the cheapest airline from ont to sea?
Frontier Airlines offers luxury First Class cabins on flights from Ontario International Airport (ONT) to Seattle Tacoma International Airport (SEA), providing a high-end travel experience. Due to its non-stop flight schedule, you can enjoy seamless journey with no layovers. Booking in advance is recommended as early bookings often result in lower fares and savings.
What's the popular airline to fly from ont to sea?
You can fly from Ontario International Airport (ONT) to Seattle Tacoma International Airport (SEA) on Southwest Airlines. This is a direct flight with no stops, making it convenient for your one-way trip. Booking in advance will help you secure the best airfare and enjoy the luxury amenities available in their First cabin.
What's the cheapest day of the week to fly from ont to sea?
The cheapest day to fly from Ontario International Airport (ONT) to Seattle Tacoma International Airport (SEA) is Sunday. Flying on Sundays can result in budget-friendly flights, making it a great option for travelers looking for low fares. For a first-class ticket with suites and fine dining, booking at least 37 days in advance may be necessary to secure the best airfare.
What's the cheapest month to fly from ont to sea?
The cheapest month to fly from Ontario (ONT) to Seattle Tacoma International (SEA) is September. Flying in this month can help you find budget-friendly flights, as it's considered an off-peak season for air travel. This can result in savings on your airfare.
Which airline/airlines fly from ont to sea?
Several airlines operate flights from Ontario International Airport (ONT) to Seattle Tacoma International Airport (SEA), including Aeromexico, Frontier Airlines, Avianca, JetBlue Airways, Southwest Airlines, Delta Airlines, United Airlines, American Airlines, and Volaris Airline. For a first-class experience with suites and fine dining, consider booking with one of these airlines for your 3-passenger group. It's recommended to book at least 37 days in advance to secure the best airfares. You can find affordable airfares on websites like fareleaders.com, which compares airfares from various airlines to help you find the cheapest flights.
What is the cheapest airfare from Ontario International to Seattle Tacoma International for a one-way trip?
You can find the cheapest flights on airlines like Frontier Airlines (F9) or Southwest Airlines (WN), with prices starting from $200 for a one-way trip.
How many advance booking days do I need to book my flight to get the best airfares on airlines?
To get the best airfares, it's recommended to book your flight at least 37 days in advance, as per the given trip details.
Can I find flights with awesome amenities like fine dining and suites in First cabin?
Yes, you can find flights with such amenities on airlines like Frontier Airlines (F9), which offers luxury cabins with suites and fine dining options.
Is it possible to book cheap flights for weekend getaways via fareleaders.com website?
Yes, fareleaders.com is a great platform to find affordable flights for weekend getaways. Use keywords like 'cheapflights' or 'cheapestflights' to find the best deals.
What are some busco tips to find the cheapest flights on airlines?
To find the cheapest flights, use busco tips like booking in advance (at least 37 days), being flexible with travel dates, and using fareleaders.com website for the best deals.

Ontario (ONT) to Seattle (SEA): Airport Information

Origin Airport Ontario International , Ontario, US
Destination Airport Seattle Tacoma International , Seattle, US
Distance 956 miles

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