Direct (non-stop) flights from Ontario (ONT) to SeaTac (SEA)
Find comprehensive flight information, schedules, and booking details for direct flights from Ontario (ONT) to SeaTac (SEA). This popular route is operated by 3 airlines, offering multiple daily departures.• Flight Duration: 2h 40m - 3h 07m (average flight time)• Distance: 962 miles (1548 km) (air miles between airports)• Daily Flights: 4-9 flights (scheduled departures per day)
Ontario (ONT)
SeaTac (SEA)
FLIGHT TIME
2h 40m - 3h 07m
FLIGHT DISTANCE
962 miles (1548 km)
2h 53m - 3h 4m
06:00
19:21
962 miles (1548 km)
April
3 (Show)
52
Flight Schedule
December 2025
Airlines with direct flights from Ontario (ONT) to SeaTac (SEA)
Route Insights
Duration variability: Flight duration on this route can vary based on aircraft type, wind conditions, and airline scheduling. Average duration is 2h 40m - 3h 07m.
Pricing patterns: April typically offers lower prices due to reduced demand outside peak travel seasons.
Best departure times: Peak departure times are 6:00, 10:00, 11:00, offering more flight options and potentially better connections.
Ontario (ONT) - SeaTac (SEA) flight price statistics
$249
ApproximateThe numbers are average prices found based on user searches for direct flights between the airports. It's calculated from the cheapest prices found per month for a round-trip with 1 adult and can vary depending on the amount of data we have for this particular route.
$196
Jan$438
Feb$217
Mar$158
Apr$158
May$398
Jun$311
Jul$258
Aug$198
Sep$198
Oct$218
Nov$238
DecRelated Information
Airports: ONT • SEA Airport
Airlines operating this route: Alaska Airlines (AS), Delta Air Lines, Frontier Airlines
Frequently Asked Questions
How many flights operate from ONT to SEA?
There are 8 direct flights operating from ONT to SEA. Approximately 4-9 flights daily.
Which airlines operate flights from ONT to SEA?
3 airlines operate on this route: Alaska Airlines, Delta Air Lines, Frontier Airlines.
How long is the flight from ONT to SEA?
The flight duration from ONT to SEA is approximately 2h 40m - 3h 07m.
What is the distance from ONT to SEA?
The distance from ONT to SEA is 962 miles (1548 km).
What is the flight time range for this route?
Flight times on this route range from 2h 53m - 3h 4m.
What are the earliest and latest flight departure times?
The earliest flight departs at 06:00 and the latest flight departs at 19:21.
What is the cheapest month to fly from ONT to SEA?
April is typically the cheapest month to fly on this route.
How many flights operate per week on this route?
Approximately 52 flights operate per week from ONT to SEA.
What types of aircraft operate on this route?
This route is served by Boeing 737-800 (winglets) Passenger/BBJ2, Embraer 175 (Enhanced Winglets), Boeing 737-900 (winglets) Passenger/BBJ3, Boeing 737MAX 9 Passenger, Airbus A321.
What is the average flight price from ONT to SEA?
The average flight price for a round-trip ticket from ONT to SEA is approximately $249 USD. Prices can vary based on booking time, season, and airline.
When is the best time to book flights from ONT to SEA for the lowest prices?
April is typically the cheapest month to fly from ONT to SEA. Booking in advance and avoiding peak travel seasons can help you find better deals.
How many airlines offer flights from ONT to SEA?
3 airlines offer direct flights from ONT to SEA, providing travelers with multiple options for scheduling and pricing.
How far is SEA from ONT?
The distance from ONT to SEA is 962 miles (1548 km). This is a long-haul flight route.
How long does it take to fly from ONT to SEA?
The flight time from ONT to SEA is approximately 2h 40m - 3h 07m. Actual flight duration may vary based on weather conditions, aircraft type, and routing.