Cheap Flight Tickets from Seattle (SEA) to Ontario (ONT), Starting at $163

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

$192

F9 Frontier Airlines • 1 stop • 12h

Sep 25 – Sep 27

The cheapest round trip flight from Seattle to Ontario (SEA-ONT-SEA) is currently $192

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Cheapest Direct Flight

$224

F9 Frontier Airlines • nonstop • 4h 12m

Sep 25

The cheapest nonstop flight from Seattle to Ontario (SEA-ONT) is currently $224

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Fastest Flight

4h 2m

The fastest nonstop flight from Seattle to Ontario (SEA-ONT) takes 4h 2m

Top Airlines Flying from Seattle to Ontario

Southwest Airlines-WN

Southwest Airlines

Delta Airline, DL

Delta Airlines

United Airlines, UA

United Airlines

Alaska Airlines -AS

Alaska 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.

Sep 25 - Sep 27, Economy
F9
Seattle → Ontario
12h
4:27 PM - 11:47 PM • 1 stop
F9
Seattle → Ontario
21h 58m
8:24 PM - 9:42 AM • 1 stop
$192
Frontier Airlines
Sep 25 - Sep 27, Economy
F9
Seattle → Ontario
22h 4m
7:45 PM - 9:09 AM • 1 stop
F9
Seattle → Ontario
14h 13m
6:15 AM - 3:08 PM • 1 stop
$192
Frontier Airlines
Sep 25 - Sep 27, Economy
WN
Seattle → Ontario
6h 45m
6:15 PM - 10:20 PM • 1 stop
WN
Seattle → Ontario
8h 20m
3:05 PM - 8:05 PM • 1 stop
$224
Southwest Airlines
Sep 25 - Sep 27, Economy
AS
Seattle → Ontario
7h 13m
3:51 PM - 8:24 PM • 1 stop
AS
Seattle → Ontario
7h 18m
7:03 AM - 11:41 AM • 1 stop
$278
Alaska Airlines
Sep 25 - Sep 27, Economy
UA
Seattle → Ontario
8h 33m
3:18 PM - 8:31 PM • 1 stop
UA
Seattle → Ontario
4h 15m
12:55 PM - 3:50 PM • nonstop
$301
United Airlines
Sep 25 - Sep 27, Economy
DL
Seattle → Ontario
4h 10m
2:29 PM - 5:19 PM • nonstop
DL
Seattle → Ontario
4h 4m
5:55 PM - 8:39 PM • nonstop
$666
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 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 F9 : USD 192
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 9:45 pm

Essential Information for Booking Flights from Seattle (SEA) - AI Insights

What's the cheapest airline from sea to ont?
You can find the cheapest flights from Seattle to Ontario with a round trip economy ticket. Frontier Airlines offers affordable airfares for your 4-person group. Book in advance to secure the best Low Fares.
What's the popular airline to fly from sea to ont?
You can fly from Seattle Tacoma International Airport (sea) to Ontario International Airport (ont) with Alaska Airlines, a popular airline for round-trip flights. Alaska Airlines offers budget-friendly airfares and airfares on their website for your 4-passenger group. Book your flights in advance to get the best savings.
What's the cheapest day of the week to fly from sea to ont?
The cheapest day to fly from Seattle to Ontario is Tuesday. Flying on Tuesdays can result in low fares and budget-friendly flights. You can find cheap airline tickets by booking in advance, ideally 25 days prior to your trip.
What's the cheapest month to fly from sea to ont?
The cheapest month to fly from Seattle to Ontario is November. Booking in advance can help secure low fares. Consider flying via other airports or on different airlines to find the best options. November is a popular month for travel, so it's essential to book early to secure the best airfares.
Which airline/airlines fly from sea to ont?
Frontier Airlines and JetBlue Airways offer flights from Seattle Tacoma International Airport (SEA) to Ontario International Airport (ONT).
What is the cheapest airline to fly from Seattle Tacoma International to Ontario International for a group of 4 passengers?
Frontier Airlines (F9) offers affordable airfares for your group of 4 passengers.
How far in advance can I book airfares for a round trip from Seattle Tacoma International to Ontario International?
Book your round trip airfares at least 25 days in advance for the best deals.
Can I find cheap flights from Milwaukee to Ontario International airport?
Use our website to find awesome airfare deals on flights from Milwaukee to Ontario International airport.
How do I use the web to book my weekend flights?
Book your weekend flights directly on our website or use a busco search engine for more options.
What is the best way to find awesome airfare deals on the website?
Use our website to find awesome airfare deals and book your flights via our web.

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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