Cheap Flight Tickets from Seattle (SEA) to Ontario (ONT), Starting at $226

Good to Know: Cheapest and Fastest SEA - ONT Flights

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

Cheapest Round Trip Flight

$341

WN Southwest Airlines • 1 stop • 12h 30m

Nov 20 – Nov 22

The cheapest round trip flight from Seattle to Ontario (SEA-ONT-SEA) is currently $341

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Cheapest One way Flight

$226

F9 Frontier Airlines • 1 stop • 15h 48m

Oct 15

The cheapest one way flight from Seattle to Ontario (SEA-ONT) is currently $226

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Cheapest Direct Flight

$228

F9 Frontier Airlines • nonstop • 4h 8m

Nov 20

The cheapest nonstop flight from Seattle to Ontario (SEA-ONT) is currently $228

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Fastest Flight

3h 52m

The fastest nonstop flight from Seattle to Ontario (SEA-ONT) takes 3h 52m

Top Airlines Flying from Seattle to Ontario

Delta Airline, DL

Delta Airlines

Southwest Airlines-WN

Southwest Airlines

United Airlines, UA

United Airlines

Sun Country Airlines (SY)

Sun Country Airlines

American Airlines, AA

American Airlines

Alaska Airlines -AS

Alaska Airlines

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

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

Nov 20 - Nov 22, Economy
WN
Seattle → Ontario
12h 30m
6:15 AM - 2:05 PM • 1 stop
WN
Seattle → Ontario
15h 45m
1:20 PM - 11:05 PM • 1 stop
$341
Southwest Airlines
Nov 20 - Nov 22, Economy
AS
Seattle → Ontario
3h 55m
12:30 PM - 3:05 PM • nonstop
AS
Seattle → Ontario
4h 17m
6:00 AM - 8:57 AM • nonstop
$352
Alaska Airlines
Nov 20 - Nov 22, Economy
AS
Seattle → Ontario
3h 53m
8:58 PM - 11:31 PM • nonstop
AS
Seattle → Ontario
4h 17m
6:00 AM - 8:57 AM • nonstop
$352
Alaska Airlines
Nov 20 - Nov 22, Economy
F9
Seattle → Ontario
4h 8m
10:18 AM - 1:06 PM • nonstop
F9
Seattle → Ontario
5h 3m
11:40 AM - 12:37 PM • 2 stops
$410
Frontier Airlines
Nov 20 - Nov 22, Economy
UA
Seattle → Ontario
7h 20m
1:16 PM - 5:56 PM • 1 stop
UA
Seattle → Ontario
7h 21m
6:37 PM - 11:18 PM • 1 stop
$518
United Airlines
Nov 20 - Nov 22, Economy
AS
Seattle → Ontario
10h 26m
10:45 AM - 5:11 PM • 1 stop
AS
Seattle → Ontario
6h 47m
10:41 AM - 2:48 PM • 1 stop
$866
Alaska Airlines

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

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

FAQs on Seattle to Ontario Flights

What are the airports in Seattle?
SEA
What’s the most popular airline flying from SEA to ONT?
The most popular airline flying from Seattle to Ontario are
Can I fly from SEA to ONT non-stop?
Yes, you can fly SEA to ONT non-stop on
Which airlines fly nonstop between Seattle and Ontario?
The non-stop flights between Seattle and Ontario are .
What’s the earliest departure time from SEA to ONT Airport?
The earliest flight leaves SEA at 6:15 am and lands in ONT - Ontario International
What are the airports in Ontario?
ONT
Can I make changes to my Seattle to Ontario 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 SEA to ONT?
Read the fare rules of the Seattle to Ontario 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 Seattle and Ontario?
operate flights between Seattle and Ontario
How long does a flight from Seattle to Ontario take?
It takes approximately 3 hour to fly non-stop from SEA to ONT, which is 956.13 miles by air.
Which airlines provide the cheapest flights from Seattle (SEA) to Ontario (ONT) ?
In the past couple of days, the cheapest tickets to ONT from SEA were found on F9 : USD 226
Do I need a passport to fly between SEA and ONT?
No
What’s the latest departure time from SEA to ONT ?
The last flight leaves SEA at 9:16 pm

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

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

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