$53 Find Cheap Flights from Seattle to Ontario - Compare and Save

These are the earliest and latest flight times available from Seattle to Ontario:

• Earliest: departs at 7:30 am and lands at 10:14 am
• Latest: departs at 9:20 pm and lands at 12:04 am.

The flight takes about 2h 44m.

Four cabin classes are available on flights from Seattle to Ontario:

• Economy Class
• Premium Economy Class
• Business Class
• First Class

Prices vary by airline.

A nonstop flight from Seattle to Ontario takes 2h 44m, covering 956 miles.

No, a passport is not required for this domestic route, but you will need a real ID-compliant driver's license, a state ID or another TSA-accepted form of identification.

Round-trip flights from Seattle to Ontario range from $207 to $387, with an average of $295 over the past 12 months. Anything below $207 counts as a good deal.

Last-minute fares on this route (booked within two weeks of departure) run 37% above the $295 route average. Book 15 weeks before departure for the lowest fares.

On this route, layover flights are cheaper than nonstop options on average. Layover fares average $279 round-trip via Sacramento Intl (SMF), compared to $296 for nonstop.

There is no standard. Checked-bag policies vary by airline on this route. Most carriers charge $35–$100 for the first checked bag in economy. Premium fares and elite-status bookings typically include a free checked bag.

The Boeing 737-800 Passenger/BBJ2 (winglets) family is used most often on this route, operated mainly by Alaska Airlines. Other aircraft seen on the route include Airbus A321neo variants.

Morning is the busiest departure period on Seattle to Ontario flights, with 43% of flights leaving in that window. Afternoon departures account for 29%, evening flights for 28%, and night flights for 0%.

Two airlines offer in-flight Wi-Fi on Seattle to Ontario flights:

• Alaska Airlines
• Delta

Pricing varies by airline and fare class. Some plans are included with the ticket or loyalty program; others are paid add-ons priced by flight length.

One-way fares from Seattle to Ontario are currently lower than usual. Average one-way flight prices are about $85, which is 56% below the typical average for this route.

Ontario Airport (ONT) hosts 5 major car rental companies, with daily rates starting from around $18 for economy cars. Top options include:

• Fox
• Thrifty
• Europcar
• Dollar
• Alamo

Flights from Seattle to Ontario usually depart from Seattle/Tacoma Intl (SEA) and arrive at Ontario (ONT).

One-stop flights from Seattle to Ontario most commonly connect through:

• Denver Intl (DEN) - 43% of one-stop connections
• Sacramento Intl (SMF) - 32% of one-stop connections
• San Francisco (SFO) - 11% of one-stop connections
• Las Vegas Harry Reid Intl (LAS) - 7% of one-stop connections

Yes. Flexible dates can save you up to 22% on flights from Seattle to Ontario. Wednesday is the cheapest departure day at $270 round-trip on average, while Sunday is the most expensive at $345, a difference of $75.

KAYAK's flexible dates feature shows options up to 3 days before and after your selected dates, making it easier to compare nearby fares.

3 airlines operate flights between Seattle and Ontario. The airlines offering nonstop flights on this route include:

• Alaska Airlines
• Delta
• Frontier

Flying via Portland (PDX) gives the shortest average 1-stop total travel time at 4h 36m, compared with 4h 40m via Sacramento Intl (SMF) and 4h 56m via San Francisco (SFO).

Some of the most popular sights in Ontario are Ontario Convention Center and Cucamonga-Guasti Regional Park. These are among the most viewed places in Ontario on KAYAK.

Among airlines operating Seattle to Ontario flights:

• Frontier: offers free seat selection
• Alaska Airlines: offers free seat selection
• Delta: offers extra legroom; offers free seat selection

Extra legroom and free seat selection availability depends on fare class and route.

Here are some options for this route, based on selected ticket types and cabin classes:

• Frontier: a cabin bag and a checked bag in Economy Class
• Alaska Airlines: a cabin bag and a checked bag in Business Class
• Delta: a cabin bag and a checked bag in First Class

Bag allowance can vary by ticket type, cabin class, route and airline, so always check the fare details before booking.

Yes, public bus and rail transportation is available from Ontario Airport. Omnitrans buses stop at the airport every 15 minutes on weekdays and every 30 minutes on weekends.

Yes, SEA offers the Sunflower Lanyard Program for travelers with hidden disabilities who may need extra help while traveling. Lanyards can be requested at the pre-security ticketing-level information desk between checkpoints 4 and 5, the pre-security baggage-claim-level information desk in Gina Marie Lindsey Arrivals Hall or the post-security information desk in Concourse A.

Yes, Ontario Airport has pet relief areas inside and outside the terminals. Outdoor areas are at the far end of the terminal buildings and indoor areas are near gates 210 and 410. Waste disposal bags and bins are provided for cleanup.

Yes, the ONT USO lounge gives military members and their families a place to relax. Free internet, entertainment, food and drinks are available. It is located across from parking lot F.