Cheap Flight Tickets from Ontario (ONT) to Seattle (SEA), Starting at $180

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

$280

F9 Frontier Airlines • 1 stop • 45h 17m

Jul 30 – Aug 07

The cheapest round trip flight from Ontario to Seattle (ONT-SEA-ONT) is currently $280

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Cheapest Direct Flight

$180

DL Delta Airlines • nonstop • 4h 11m

Jul 30

The cheapest nonstop flight from Ontario to Seattle (ONT-SEA) is currently $180

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Fastest Flight

4h

The fastest nonstop flight from Ontario to Seattle (ONT-SEA) takes 4h

Top Airlines Flying from Ontario to Seattle

Southwest Airlines-WN

Southwest Airlines

Delta Airline, DL

Delta Airlines

United Airlines, UA

United Airlines

American Airlines, AA

American Airlines

Alaska Airlines -AS

Alaska Airlines

Hawaiian Airlines-HA

Hawaiian Airlines

Aeromexico Airline (AM)

Aeromexico

Sun Country Airlines (SY)

Sun Country Airlines

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.

Jul 30 - Aug 07, Economy
F9
Ontario → Seattle
45h 17m
6:00 AM - 9:17 AM • 1 stop
F9
Ontario → Seattle
18h 30m
8:53 PM - 8:03 AM • 1 stop
$280
Frontier Airlines
Jul 07 - Jul 30, Economy
AS
Ontario → Seattle
4h 9m
7:00 AM - 11:53 AM • 1 stop
F9
Ontario → Seattle
4h 11m
11:54 AM - 2:45 PM • nonstop
$368
Alaska Airlines
Jul 07 - Jul 30, Economy
UA
Ontario → Seattle
7h 37m
1:50 PM - 6:47 PM • 1 stop
UA
Ontario → Seattle
8h 32m
7:00 AM - 12:12 PM • 1 stop
$481
United Airlines
Jul 31 - Aug 08, Economy
B6
Ontario → Seattle
97h 28m
11:51 PM - 10:39 AM • 3 stops
F9
Ontario → Seattle
4h 15m
12:19 PM - 3:14 PM • nonstop
$750
JetBlue Airways
Jul 07 - Jul 30, Economy
AS
Ontario → Seattle
7h 35m
5:32 PM - 10:27 PM • 1 stop
AS
Ontario → Seattle
32h 29m
11:57 PM - 7:46 PM • 2 stops
$1343
Alaska Airlines
Jul 31 - Aug 08, Economy
AS
Ontario → Seattle
12h 23m
7:00 AM - 2:43 PM • 1 stop
AS
Ontario → Seattle
32h 29m
11:57 PM - 7:46 PM • 2 stops
$1382
Alaska 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 AS : USD 1343
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 11:51 pm

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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