Cheap Flight Tickets from Seattle (SEA) to Ontario (ONT), Starting at $139

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

$287

DL Delta Airlines • nonstop • 4h 14m

Jan 02 – Jan 09

The cheapest round trip flight from Seattle to Ontario (SEA-ONT-SEA) is currently $287

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Cheapest One way Flight

$139

AS Alaska Airlines • nonstop • 4h 5m

Oct 30

The cheapest one way flight from Seattle to Ontario (SEA-ONT) is currently $139

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Cheapest Direct Flight

$267

DL Delta Airlines • nonstop • 4h 6m

Nov 13

The cheapest nonstop flight from Seattle to Ontario (SEA-ONT) is currently $267

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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

Alaska Airlines -AS

Alaska Airlines

United Airlines, UA

United 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.

Jan 02 - Jan 09, Economy
DL
Seattle → Ontario
4h 14m
8:25 AM - 11:19 AM • nonstop
DL
Seattle → Ontario
5h
9:59 AM - 12:59 PM • nonstop
$287
Delta Airlines
Jan 02 - Jan 09, Economy
DL
Seattle → Ontario
4h 8m
2:10 PM - 4:58 PM • nonstop
DL
Seattle → Ontario
4h 14m
5:35 PM - 8:29 PM • nonstop
$287
Delta Airlines
Jan 02 - Jan 09, Economy
DL
Seattle → Ontario
10h
5:59 PM - 11:59 PM • 1 stop
DL
Seattle → Ontario
4h 14m
5:35 PM - 8:29 PM • nonstop
$327
Delta Airlines
Nov 13 - Nov 16, Economy
AS
Seattle → Ontario
11h 42m
10:17 AM - 5:19 PM • 1 stop
AS
Seattle → Ontario
11h 46m
2:59 PM - 10:05 PM • 1 stop
$332
Alaska Airlines
Nov 13 - Nov 16, Economy
AS
Seattle → Ontario
8h 37m
12:02 PM - 5:19 PM • 1 stop
AS
Seattle → Ontario
10h 21m
9:20 AM - 3:41 PM • 1 stop
$332
Alaska Airlines
Nov 13 - Nov 16, Economy
WN
Seattle → Ontario
9h 5m
11:10 AM - 4:55 PM • 1 stop
WN
Seattle → Ontario
13h 25m
10:35 AM - 6:40 PM • 1 stop
$346
Southwest 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 8:25 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 DL : USD 412
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 8:11 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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