Seattle to Ontario (SEA-ONT): nonstop upgrade & award space

Alaska Airlines, Delta Air Lines, and Frontier Airlines fly nonstop between Seattle (SEA) and Ontario (ONT), roughly 56 times a week. The timetable below shows the nonstop scheduled at 2h 32m to 2h 51m for the 957 miles. 2LNR checks confirmed upgrade and award space on Alaska Airlines and Delta Air Lines flights on this route, so you can see which departures have space before you book.

Schedule last confirmed . Departure times come from 2LNR's schedule data; confirm with the airline before you book.

Updated .

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56
Flights a week, 4-week average
2h 32m to 2h 51m
Scheduled flight time
957 mi
Nonstop distance
Free
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Seattle to Ontario flight schedule

Scheduled nonstop departures for SEA to ONT starting October 23, 2026, last checked against our schedule feed on October 18, 2026. Airlines retime and cancel flights, so confirm with the airline before you book.

Schedule data dated .

Scheduled nonstop departures from Seattle (SEA) to Ontario (ONT)
Date Flight Airline Departs SEA Arrives ONT Duration Aircraft
AS 476Alaska Airlines, Inc.07:3010:172h 47mBoeing 737-900
DL 4070Delta Air Lines08:2511:162h 51mEmbraer E175
AS 571Alaska Airlines, Inc.10:3113:162h 45mBoeing 737 MAX 9
F9 2276Frontier Airlines10:5313:432h 50mAirbus A320neo
DL 4031Delta Air Lines14:3017:122h 42mEmbraer E175
AS 592Alaska Airlines, Inc.15:2818:002h 32mBoeing 737 MAX 9
DL 3987Delta Air Lines19:5622:432h 47mEmbraer E175
AS 489Alaska Airlines, Inc.21:0623:422h 36mBoeing 737-900
AS 476Alaska Airlines, Inc.07:3010:172h 47mBoeing 737-800
AS 571Alaska Airlines, Inc.10:3113:162h 45mBoeing 737 MAX 9
F9 2276Frontier Airlines11:1514:032h 48mAirbus A321
DL 4031Delta Air Lines14:3017:122h 42mEmbraer E175
AS 592Alaska Airlines, Inc.15:2818:002h 32mBoeing 737 MAX 9
DL 3987Delta Air Lines19:5622:432h 47mEmbraer E175
AS 489Alaska Airlines, Inc.21:0623:452h 39mBoeing 737-900
AS 476Alaska Airlines, Inc.07:3010:172h 47mBoeing 737-900
DL 4070Delta Air Lines08:2511:162h 51mEmbraer E175
F9 2276Frontier Airlines10:0312:532h 50mAirbus A320neo
AS 571Alaska Airlines, Inc.10:3113:162h 45mBoeing 737-900
DL 4031Delta Air Lines14:3017:122h 42mEmbraer E175
AS 592Alaska Airlines, Inc.15:2818:002h 32mBoeing 737 MAX 9
DL 3987Delta Air Lines19:5622:432h 47mEmbraer E175
AS 489Alaska Airlines, Inc.21:0623:422h 36mBoeing 737 MAX 9
AS 476Alaska Airlines, Inc.07:3010:172h 47mBoeing 737-700
DL 4070Delta Air Lines08:2511:162h 51mEmbraer E175
AS 571Alaska Airlines, Inc.10:3113:162h 45mBoeing 737-900
F9 2276Frontier Airlines10:5313:432h 50mAirbus A320neo
DL 4031Delta Air Lines14:3017:122h 42mEmbraer E175
AS 592Alaska Airlines, Inc.15:2818:002h 32mBoeing 737 MAX 9
DL 3987Delta Air Lines19:5622:432h 47mEmbraer E175
AS 489Alaska Airlines, Inc.21:0623:422h 36mBoeing 737-900
AS 476Alaska Airlines, Inc.07:3010:172h 47mBoeing 737-800
DL 4070Delta Air Lines08:2511:162h 51mEmbraer E175
AS 571Alaska Airlines, Inc.10:3113:162h 45mBoeing 737-800
F9 2276Frontier Airlines12:4615:322h 46mAirbus A321
DL 4031Delta Air Lines14:3017:122h 42mEmbraer E175
AS 592Alaska Airlines, Inc.15:2818:002h 32mBoeing 737-900
DL 3987Delta Air Lines19:5622:432h 47mEmbraer E175
AS 489Alaska Airlines, Inc.21:0623:452h 39mBoeing 737-900
AS 476Alaska Airlines, Inc.07:3010:172h 47mBoeing 737-800

Showing the first 40 of 56 scheduled SEA to ONT departures across 7 days with service, starting October 23, 2026. Every remaining date is on the interactive map.

Departure and arrival times are local at their own airport, so an arrival can fall on a different local date than the departure; the duration column is the true elapsed flying time. A dash means the airline hasn't filed that value in the schedule data we hold. Aircraft are the equipment the airline filed, named where the code pins down one type and shown as the family or the bare code where it doesn't. Swaps can happen up to departure.

See every SEA to ONT date on the interactive map

Aircraft on the Seattle to Ontario nonstop

In the schedule table on this page, Alaska Airlines flies the Boeing 737-900, the Boeing 737 MAX 9, the Boeing 737-800, and the Boeing 737-700. Delta Air Lines flies the Embraer E175. Frontier Airlines flies the Airbus A320neo and the Airbus A321. Each linked aircraft page shows where that airline schedules it. Airlines can swap aircraft up to departure.

Confirmed upgrade & award space on SEA to ONT departures

2LNR tracks confirmed upgrade and award space on Alaska Airlines and Delta Air Lines, segment by segment and date by date. Open the calendar for Seattle to Ontario to see which departures have space, the next 14 days free on every product and the full horizon on Pro.

In the 7 days to October 19, 2026, 2LNR checked award space on Seattle to Ontario departures from October 19 to November 1. Alaska Airlines had space open on 14 of 14 dates checked and Delta Air Lines on 14 of 14.

See real availability

Confirmed upgrade or award seats by date on the SEA to ONT departures 2LNR tracks, checked against live inventory so you know what's open before you book.

Set an alert

Premium inventory turns over fast. Watch this route on Pro and 2LNR notifies you when space appears on a date you're tracking.

Plan on the map

See SEA to ONT on the interactive route map, with schedules, connections, and route statistics.

Airlines flying Seattle to Ontario nonstop

Carriers operating SEA to ONT nonstop in the current schedule. Where 2LNR tracks the carrier, its departures show confirmed upgrade or award space by date.

See SEA to ONT on the interactive map →

Frequently asked questions about SEA to ONT

How long is the flight from Seattle (SEA) to Ontario (ONT)?
Scheduled flight times from Seattle (SEA) to Ontario (ONT) run from 2h 32m to 2h 51m across the departures in the schedule table on this page. The nonstop covers about 957 miles, and airlines adjust scheduled times by season, so confirm with the airline before you book.
Which airlines fly nonstop from SEA to ONT?
Alaska Airlines, Delta Air Lines, and Frontier Airlines fly SEA to ONT nonstop. 2LNR tracks confirmed upgrade and award space on Alaska Airlines and Delta Air Lines.
How many flights a week are there from SEA to ONT?
About 56 nonstop flights a week run between Seattle (SEA) and Ontario (ONT) in the current schedule, operated by Alaska Airlines, Delta Air Lines, and Frontier Airlines. Frequency shifts by season, and the schedule table on this page shows what is scheduled next.
What time do flights from SEA to ONT depart?
Scheduled SEA to ONT nonstops in the next 7 days with service leave between 07:30 and 21:06, local time at Seattle. The schedule table on this page lists every departure by date, with its arrival time and aircraft.
Which flights operate SEA to ONT nonstop?
In the schedule table on this page, SEA to ONT nonstops fly as AS 476, AS 489, AS 571, and AS 592 on Alaska Airlines; DL 3987, DL 4031, and DL 4070 on Delta Air Lines; and F9 2276 on Frontier Airlines. The table lists each departure by date with its times and aircraft.
How do I check upgrade or award availability on SEA to ONT?
Open the SEA to ONT route on the interactive map or the matrix to see confirmed upgrade and award space by date on Alaska Airlines and Delta Air Lines, the next 14 days free and the full horizon on Pro. On Pro you can also set an alert on the route and 2LNR notifies you when space opens.

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See what's open by date on this route, the next 14 days free on every product and the full horizon on Pro.

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