Cheap Flight Tickets from Seattle (SEA) to Ontario (ONT), Starting at $259

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

$336

WN Southwest Airlines • 1 stop • 6h 45m

Jul 19 – Jul 23

The cheapest round trip flight from Seattle to Ontario (SEA-ONT-SEA) is currently $336

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Cheapest Direct Flight

$427

DL Delta Airlines • nonstop • 4h 11m

Jul 19

The cheapest nonstop flight from Seattle to Ontario (SEA-ONT) is currently $427

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Fastest Flight

3h 58m

The fastest nonstop flight from Seattle to Ontario (SEA-ONT) takes 3h 58m

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

American Airlines, AA

American 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.

Jul 19 - Jul 23, Economy
WN
Seattle → Ontario
6h 45m
5:00 AM - 9:05 AM • 1 stop
WN
Seattle → Ontario
15h 55m
2:00 PM - 11:55 PM • 1 stop
$336
Southwest Airlines
Jul 19 - Jul 23, Economy
DL
Seattle → Ontario
4h 11m
2:30 PM - 5:21 PM • nonstop
DL
Seattle → Ontario
4h 2m
5:45 PM - 8:27 PM • nonstop
$427
Delta Airlines
Jul 19 - Jul 23, Economy
DL
Seattle → Ontario
4h 12m
8:25 AM - 11:17 AM • nonstop
DL
Seattle → Ontario
4h 2m
5:45 PM - 8:27 PM • nonstop
$427
Delta Airlines
Jul 19 - Jul 23, Economy
DL
Seattle → Ontario
4h 13m
7:59 PM - 10:52 PM • nonstop
DL
Seattle → Ontario
4h
2:00 PM - 4:40 PM • nonstop
$427
Delta Airlines
Jul 05 - Jul 12, Economy
DL
Seattle → Ontario
4h 4m
2:35 PM - 5:19 PM • nonstop
DL
Seattle → Ontario
4h 8m
7:17 PM - 10:05 PM • nonstop
$627
Delta Airlines
Jul 05 - Jul 12, Economy
DL
Seattle → Ontario
4h 11m
7:50 PM - 10:41 PM • nonstop
DL
Seattle → Ontario
4h
2:00 PM - 4:40 PM • nonstop
$627
Delta 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 5:00 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 627
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 8:33 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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