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 57 times a week. With Alaska Airlines running most of the schedule, the shape of a week is predictable, which makes an open premium seat on a given date easy to spot and quick to lose. 2LNR tracks confirmed upgrade and award space on Alaska Airlines and Delta Air Lines, on every SEA to ONT departure, so you know which flights have space before you book.

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

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57
Nonstop flights a week
957 mi
Nonstop distance
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Seattle to Ontario flight schedule

Scheduled nonstop departures for SEA to ONT, last checked against our schedule feed on September 6, 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
DL 4070Delta Air Lines08:2011:142h 54mE7W
AS 1364Alaska Airlines, Inc.08:2311:162h 53m73H
AS 571Alaska Airlines, Inc.11:2914:162h 47m73J
F9 2276Frontier Airlines11:5414:452h 51m32N
DL 4031Delta Air Lines14:2917:192h 50mE7W
AS 592Alaska Airlines, Inc.16:2219:032h 41m73H
DL 3884Delta Air Lines19:5022:402h 50mE7W
AS 489Alaska Airlines, Inc.20:3323:112h 38m7M9
DL 4070Delta Air Lines08:2011:142h 54mE7W
AS 1364Alaska Airlines, Inc.08:2311:162h 53m73H
F9 2276Frontier Airlines10:5313:452h 52m32N
AS 571Alaska Airlines, Inc.11:2914:162h 47m73J
DL 4031Delta Air Lines14:2917:192h 50mE7W
AS 592Alaska Airlines, Inc.16:2219:032h 41m73J
DL 3884Delta Air Lines19:5022:402h 50mE7W
AS 489Alaska Airlines, Inc.20:3323:112h 38m7M9
DL 4070Delta Air Lines08:2011:142h 54mE7W
AS 1364Alaska Airlines, Inc.08:2311:162h 53m7M9
F9 2276Frontier Airlines10:5313:452h 52m32N
AS 571Alaska Airlines, Inc.11:2914:162h 47m73J
DL 4031Delta Air Lines14:2917:192h 50mE7W
AS 592Alaska Airlines, Inc.16:2219:032h 41m73J
DL 3884Delta Air Lines19:5022:402h 50mE7W
AS 489Alaska Airlines, Inc.20:4323:242h 41m73H
DL 4070Delta Air Lines08:2011:142h 54mE7W
AS 1364Alaska Airlines, Inc.08:2311:162h 53m73H
F9 2276Frontier Airlines10:5313:452h 52m32N
AS 571Alaska Airlines, Inc.11:2914:162h 47m73J
DL 4031Delta Air Lines14:2917:192h 50mE7W
AS 592Alaska Airlines, Inc.16:2219:032h 41m7M9
DL 3884Delta Air Lines19:5022:402h 50mE7W
AS 489Alaska Airlines, Inc.20:4323:242h 41m73J
DL 4070Delta Air Lines08:2011:14—E7W
AS 1364Alaska Airlines, Inc.08:2311:16—73J
F9 2276Frontier Airlines10:5313:452h 52m32N
AS 571Alaska Airlines, Inc.11:2914:16—73J
DL 4031Delta Air Lines14:2917:192h 50mE7W
AS 592Alaska Airlines, Inc.16:2219:032h 41m73J
DL 3884Delta Air Lines19:5022:402h 50mE7W
AS 489Alaska Airlines, Inc.20:3323:112h 38m7M9

Showing the first 40 of 56 scheduled SEA to ONT departures across the next 7 days with service. 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 has not filed that value in the schedule data we hold. Aircraft are IATA equipment codes as filed, and can change up to departure.

See every SEA to ONT date on the interactive map

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.

See real availability

Confirmed upgrade and award seats on each SEA to ONT departure, checked against live inventory so you know what is open before you book.

Set an alert

Premium inventory turns over fast. Watch this route and 2LNR notifies you when space appears on a date you are 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. 2LNR tracks confirmed upgrade and award space on each of them.

See SEA to ONT on the interactive map →

Frequently asked questions about SEA to ONT

How far is Ontario from Seattle?
SEA to ONT covers about 957 miles nonstop. Flight times vary by aircraft and season; the schedule table on this page lists each scheduled departure with its own times.
Which airlines fly nonstop from SEA to ONT?
Alaska Airlines, Delta Air Lines, and Frontier Airlines fly the route 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 57 nonstop flights a week run between Seattle and Ontario 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 08:20 and 20:43, local time at Seattle. The schedule table on this page lists every departure by date, with its arrival time 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.

Never miss SEA to ONT upgrade or award space

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

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