--- title: "Seattle (SEA) to Ontario (ONT) flights: who flies it" description: "Alaska Airlines, Delta Air Lines and Frontier Airlines fly nonstop from SEA to ONT, about 56 flights a week. Upgrade and award space by date on 2LNR, next 14 days free." canonical: "https://2lnr.com/routes/sea-ont" url: "https://2lnr.com/routes/sea-ont.md" date_modified: "2026-10-18T05:10:47Z" --- # 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 October 18, 2026. Departure times come from 2LNR's schedule data; confirm with the airline before you book. Updated October 24, 2026. See SEA to ONT on the interactive map [Get started free](https://2lnr.com/login) 56 Flights a week, 4-week average 2h 32m to 2h 51m Scheduled flight time 957 mi Nonstop distance Free To get started ## 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. Scheduled nonstop departures from Seattle (SEA) to Ontario (ONT) | Date | Flight | Airline | Departs SEA | Arrives ONT | Duration | Aircraft | | :--- | :--- | :--- | :--- | :--- | :--- | :--- | | Fri, Oct 23 | AS 476 | Alaska Airlines, Inc. | 07:30 | 10:17 | 2h 47m | [Boeing 737-900](https://2lnr.com/seatmaps/as/737-900.md) | | Fri, Oct 23 | DL 4070 | Delta Air Lines | 08:25 | 11:16 | 2h 51m | [Embraer E175](https://2lnr.com/seatmaps/dl/e175.md) | | Fri, Oct 23 | AS 571 | Alaska Airlines, Inc. | 10:31 | 13:16 | 2h 45m | [Boeing 737 MAX 9](https://2lnr.com/seatmaps/as/737-max-9.md) | | Fri, Oct 23 | F9 2276 | Frontier Airlines | 10:53 | 13:43 | 2h 50m | [Airbus A320neo](https://2lnr.com/seatmaps/f9/a320neo.md) | | Fri, Oct 23 | DL 4031 | Delta Air Lines | 14:30 | 17:12 | 2h 42m | Embraer E175 | | Fri, Oct 23 | AS 592 | Alaska Airlines, Inc. | 15:28 | 18:00 | 2h 32m | Boeing 737 MAX 9 | | Fri, Oct 23 | DL 3987 | Delta Air Lines | 19:56 | 22:43 | 2h 47m | Embraer E175 | | Fri, Oct 23 | AS 489 | Alaska Airlines, Inc. | 21:06 | 23:42 | 2h 36m | Boeing 737-900 | | Sat, Oct 24 | AS 476 | Alaska Airlines, Inc. | 07:30 | 10:17 | 2h 47m | [Boeing 737-800](https://2lnr.com/seatmaps/as/737-800.md) | | Sat, Oct 24 | AS 571 | Alaska Airlines, Inc. | 10:31 | 13:16 | 2h 45m | Boeing 737 MAX 9 | | Sat, Oct 24 | F9 2276 | Frontier Airlines | 11:15 | 14:03 | 2h 48m | [Airbus A321](https://2lnr.com/seatmaps/f9/a321.md) | | Sat, Oct 24 | DL 4031 | Delta Air Lines | 14:30 | 17:12 | 2h 42m | Embraer E175 | | Sat, Oct 24 | AS 592 | Alaska Airlines, Inc. | 15:28 | 18:00 | 2h 32m | Boeing 737 MAX 9 | | Sat, Oct 24 | DL 3987 | Delta Air Lines | 19:56 | 22:43 | 2h 47m | Embraer E175 | | Sat, Oct 24 | AS 489 | Alaska Airlines, Inc. | 21:06 | 23:45 | 2h 39m | Boeing 737-900 | | Sun, Oct 25 | AS 476 | Alaska Airlines, Inc. | 07:30 | 10:17 | 2h 47m | Boeing 737-900 | | Sun, Oct 25 | DL 4070 | Delta Air Lines | 08:25 | 11:16 | 2h 51m | Embraer E175 | | Sun, Oct 25 | F9 2276 | Frontier Airlines | 10:03 | 12:53 | 2h 50m | Airbus A320neo | | Sun, Oct 25 | AS 571 | Alaska Airlines, Inc. | 10:31 | 13:16 | 2h 45m | Boeing 737-900 | | Sun, Oct 25 | DL 4031 | Delta Air Lines | 14:30 | 17:12 | 2h 42m | Embraer E175 | | Sun, Oct 25 | AS 592 | Alaska Airlines, Inc. | 15:28 | 18:00 | 2h 32m | Boeing 737 MAX 9 | | Sun, Oct 25 | DL 3987 | Delta Air Lines | 19:56 | 22:43 | 2h 47m | Embraer E175 | | Sun, Oct 25 | AS 489 | Alaska Airlines, Inc. | 21:06 | 23:42 | 2h 36m | Boeing 737 MAX 9 | | Mon, Oct 26 | AS 476 | Alaska Airlines, Inc. | 07:30 | 10:17 | 2h 47m | [Boeing 737-700](https://2lnr.com/seatmaps/as/737-700.md) | | Mon, Oct 26 | DL 4070 | Delta Air Lines | 08:25 | 11:16 | 2h 51m | Embraer E175 | | Mon, Oct 26 | AS 571 | Alaska Airlines, Inc. | 10:31 | 13:16 | 2h 45m | Boeing 737-900 | | Mon, Oct 26 | F9 2276 | Frontier Airlines | 10:53 | 13:43 | 2h 50m | Airbus A320neo | | Mon, Oct 26 | DL 4031 | Delta Air Lines | 14:30 | 17:12 | 2h 42m | Embraer E175 | | Mon, Oct 26 | AS 592 | Alaska Airlines, Inc. | 15:28 | 18:00 | 2h 32m | Boeing 737 MAX 9 | | Mon, Oct 26 | DL 3987 | Delta Air Lines | 19:56 | 22:43 | 2h 47m | Embraer E175 | | Mon, Oct 26 | AS 489 | Alaska Airlines, Inc. | 21:06 | 23:42 | 2h 36m | Boeing 737-900 | | Tue, Oct 27 | AS 476 | Alaska Airlines, Inc. | 07:30 | 10:17 | 2h 47m | Boeing 737-800 | | Tue, Oct 27 | DL 4070 | Delta Air Lines | 08:25 | 11:16 | 2h 51m | Embraer E175 | | Tue, Oct 27 | AS 571 | Alaska Airlines, Inc. | 10:31 | 13:16 | 2h 45m | Boeing 737-800 | | Tue, Oct 27 | F9 2276 | Frontier Airlines | 12:46 | 15:32 | 2h 46m | Airbus A321 | | Tue, Oct 27 | DL 4031 | Delta Air Lines | 14:30 | 17:12 | 2h 42m | Embraer E175 | | Tue, Oct 27 | AS 592 | Alaska Airlines, Inc. | 15:28 | 18:00 | 2h 32m | Boeing 737-900 | | Tue, Oct 27 | DL 3987 | Delta Air Lines | 19:56 | 22:43 | 2h 47m | Embraer E175 | | Tue, Oct 27 | AS 489 | Alaska Airlines, Inc. | 21:06 | 23:45 | 2h 39m | Boeing 737-900 | | Wed, Oct 28 | AS 476 | Alaska Airlines, Inc. | 07:30 | 10:17 | 2h 47m | Boeing 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](https://2lnr.com/seatmaps/as/737-900.md), the [Boeing 737 MAX 9](https://2lnr.com/seatmaps/as/737-max-9.md), the [Boeing 737-800](https://2lnr.com/seatmaps/as/737-800.md), and the [Boeing 737-700](https://2lnr.com/seatmaps/as/737-700.md). Delta Air Lines flies the [Embraer E175](https://2lnr.com/seatmaps/dl/e175.md). Frontier Airlines flies the [Airbus A320neo](https://2lnr.com/seatmaps/f9/a320neo.md) and the [Airbus A321](https://2lnr.com/seatmaps/f9/a321.md). 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. - [Alaska Airlines (AS) route map](https://2lnr.com/routes/airlines/as.md)\ [The aircraft AS flies](https://2lnr.com/seatmaps/as.md) - [Delta Air Lines (DL) route map](https://2lnr.com/routes/airlines/dl.md)\ [The aircraft DL flies](https://2lnr.com/seatmaps/dl.md) - [Frontier Airlines (F9) route map](https://2lnr.com/routes/airlines/f9.md)\ [The aircraft F9 flies](https://2lnr.com/seatmaps/f9.md) 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. Flying the other way? See [ONT to SEA upgrade and award space](https://2lnr.com/routes/ont-sea.md). Award seats rather than schedules? See [Alaska Airlines award availability](https://2lnr.com/awards/as.md) or [Delta Air Lines award availability](https://2lnr.com/awards/dl.md). Looking beyond this route? See [every route from Seattle (SEA)](https://2lnr.com/routes/sea.md), or [every route from Ontario (ONT)](https://2lnr.com/routes/ont.md). Nonstops to Ontario (ONT) from other airports within 150 miles of Seattle (SEA): - [Portland (PDX) to Ontario (ONT)](https://2lnr.com/routes/pdx-ont.md), 129 miles from SEA Nonstops from Seattle (SEA) to other airports within 150 miles of Ontario (ONT): - [Seattle (SEA) to Santa Ana (SNA)](https://2lnr.com/routes/sea-sna.md), 30 miles from ONT - [Seattle (SEA) to Long Beach (LGB)](https://2lnr.com/routes/sea-lgb.md), 36 miles from ONT - [Seattle (SEA) to Burbank (BUR)](https://2lnr.com/routes/sea-bur.md), 45 miles from ONT - [Seattle (SEA) to Los Angeles (LAX)](https://2lnr.com/routes/sea-lax.md), 48 miles from ONT - [Seattle (SEA) to Palm Springs (PSP)](https://2lnr.com/routes/sea-psp.md), 64 miles from ONT Distances are great-circle between the airports, not driving distance. - [How Alaska upgrades clear](https://2lnr.com/about/as/upgrades.md) - [How to read award availability by date](https://2lnr.com/guides/award-availability.md) ## Never miss SEA to ONT upgrade or award space See what's open by date on this route, the next 14 days free on every product and the full horizon on Pro. [Get started free](https://2lnr.com/login)