Seattle (SEA) to Denver (DEN) flights: who flies it

Seattle to Denver flight schedule

Scheduled nonstop departures for SEA to DEN 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 Denver (DEN)
Date	Flight	Airline	Departs SEA	Arrives DEN	Duration	Aircraft
Fri, Oct 23	UA 2601	United Airlines	05:00	08:45	2h 45m	Airbus A321neo family
Fri, Oct 23	AS 682	Alaska Airlines, Inc.	07:08	11:02	2h 54m	Boeing 737-900
Fri, Oct 23	UA 1505	United Airlines	08:30	12:22	2h 52m	Boeing 737-800
Fri, Oct 23	DL 1358	Delta Air Lines	09:05	12:49	2h 44m	Airbus A220-300
Fri, Oct 23	AS 535	Alaska Airlines, Inc.	10:13	14:08	2h 55m	Boeing 737-900
Fri, Oct 23	UA 2033	United Airlines	12:43	16:34	2h 51m	Airbus A321neo family
Fri, Oct 23	AS 602	Alaska Airlines, Inc.	13:16	16:59	2h 43m	Boeing 737-900
Fri, Oct 23	DL 2543	Delta Air Lines	13:55	17:47	2h 52m	Airbus A220-300
Fri, Oct 23	UA 333	United Airlines	14:27	18:17	2h 50m	Boeing 737 MAX 8
Fri, Oct 23	UA 757	United Airlines	15:55	19:45	2h 50m	Boeing 737 MAX 9
Fri, Oct 23	F9 3406	Frontier Airlines	16:27	20:17	2h 50m	Airbus A321neo family
Fri, Oct 23	UA 1218	United Airlines	18:05	21:49	2h 44m	Airbus A321neo family
Fri, Oct 23	AS 310	Alaska Airlines, Inc.	18:54	22:37	2h 43m	Boeing 737-900
Fri, Oct 23	DL 2851	Delta Air Lines	20:00	23:55	2h 55m	Airbus A220-300
Sat, Oct 24	UA 2601	United Airlines	05:00	08:45	2h 45m	Airbus A321neo family
Sat, Oct 24	AS 682	Alaska Airlines, Inc.	07:08	11:02	2h 54m	Boeing 737 MAX 9
Sat, Oct 24	UA 1505	United Airlines	08:30	12:22	2h 52m	Boeing 737-800
Sat, Oct 24	DL 1358	Delta Air Lines	09:05	12:49	2h 44m	Airbus A220-300
Sat, Oct 24	AS 535	Alaska Airlines, Inc.	10:13	14:08	2h 55m	Boeing 737 MAX 9
Sat, Oct 24	AS 602	Alaska Airlines, Inc.	13:16	16:59	2h 43m	Boeing 737-900
Sat, Oct 24	DL 2543	Delta Air Lines	13:55	17:47	2h 52m	Airbus A220-300
Sat, Oct 24	UA 757	United Airlines	15:55	19:45	2h 50m	Boeing 737 MAX 9
Sat, Oct 24	F9 3406	Frontier Airlines	16:27	20:17	2h 50m	Airbus A321neo family
Sat, Oct 24	AS 310	Alaska Airlines, Inc.	18:54	22:37	2h 43m	Boeing 737-900
Sat, Oct 24	DL 2851	Delta Air Lines	20:00	23:55	2h 55m	Airbus A220-300
Sun, Oct 25	AS 682	Alaska Airlines, Inc.	07:08	11:02	2h 54m	Boeing 737-900
Sun, Oct 25	UA 1505	United Airlines	08:30	12:22	2h 52m	Boeing 737-800
Sun, Oct 25	DL 1358	Delta Air Lines	09:05	12:49	2h 44m	Airbus A220-300
Sun, Oct 25	AS 535	Alaska Airlines, Inc.	10:13	14:08	2h 55m	Boeing 737 MAX 9
Sun, Oct 25	UA 1534	United Airlines	12:44	16:35	2h 51m	Airbus A321neo family
Sun, Oct 25	AS 602	Alaska Airlines, Inc.	13:16	16:59	2h 43m	Boeing 737-900
Sun, Oct 25	DL 2543	Delta Air Lines	13:55	17:47	2h 52m	Airbus A220-300
Sun, Oct 25	UA 725	United Airlines	15:02	18:43	2h 41m	Boeing 737-900
Sun, Oct 25	UA 1194	United Airlines	15:51	19:35	2h 44m	Boeing 737-800
Sun, Oct 25	UA 757	United Airlines	15:54	19:45	2h 51m	Boeing 737 MAX 8
Sun, Oct 25	F9 3406	Frontier Airlines	16:27	20:17	2h 50m	Airbus A321neo family
Sun, Oct 25	AS 310	Alaska Airlines, Inc.	18:54	22:37	2h 43m	Boeing 737-900
Sun, Oct 25	UA 1218	United Airlines	19:04	22:45	2h 41m	Boeing 737-800
Sun, Oct 25	DL 2851	Delta Air Lines	20:00	23:55	2h 55m	Airbus A220-300
Mon, Oct 26	AS 682	Alaska Airlines, Inc.	07:08	11:02	2h 54m	Boeing 737-900

Showing the first 40 of 89 scheduled SEA to DEN 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 DEN date on the interactive map

Aircraft on the Seattle to Denver nonstop

In the schedule table on this page, United Airlines flies the Airbus A321neo family, the Boeing 737-800, the Boeing 737 MAX 8, the Boeing 737 MAX 9, and the Boeing 737-900. Alaska Airlines flies the Boeing 737-900 and the Boeing 737 MAX 9. Delta Air Lines flies the Airbus A220-300. Frontier Airlines flies the Airbus A321neo family. Each linked aircraft page shows where that airline schedules it. Airlines can swap aircraft up to departure.

Confirmed upgrade & award space on SEA to DEN 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 Denver 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 Denver departures from October 19 to November 1. Alaska Airlines had space open on 9 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 DEN 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 DEN on the interactive route map, with schedules, connections, and route statistics.

Airlines flying Seattle to Denver nonstop

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

See SEA to DEN on the interactive map →

Frequently asked questions about SEA to DEN

How long is the flight from Seattle (SEA) to Denver (DEN)?

Scheduled flight times from Seattle (SEA) to Denver (DEN) run from 2h 41m to 2h 55m across the departures in the schedule table on this page. The nonstop covers about 1,022 miles, and airlines adjust scheduled times by season, so confirm with the airline before you book.

Which airlines fly nonstop from SEA to DEN?

United Airlines, Alaska Airlines, Delta Air Lines, and Frontier Airlines fly SEA to DEN 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 DEN?

About 84 nonstop flights a week run between Seattle (SEA) and Denver (DEN) in the current schedule, operated by United Airlines, 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 DEN depart?

Scheduled SEA to DEN nonstops in the next 7 days with service leave between 05:00 and 20:00, 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 DEN nonstop?

The schedule table on this page lists 17 flight numbers for SEA to DEN nonstops, including UA 757 and UA 1505 on United Airlines; AS 535, AS 602, and AS 682 on Alaska Airlines; DL 1358 and DL 2543 on Delta Air Lines; and F9 3406 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 DEN?

Open the SEA to DEN 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.