Denver to Seattle Flight Time & Schedules

How Much Time Should You Allow for a Flight from Denver to Seattle?

A nonstop flight from Denver International Airport (DEN) to Seattle-Tacoma International Airport (SEA) generally takes around 3 hours to 3 hours 11 minutes on current schedules. The route covers approximately 1,020 miles (about 1,640 km).

Travelers have a good selection of direct services. Alaska Airlines, Delta Air Lines, Frontier Airlines, Southwest Airlines and United Airlines currently operate nonstop flights between Denver and Seattle. American Airlines is listed to begin service later in 2026, so it is not included here as a current operator.

Connecting flights are also available. Some relatively quick one-stop combinations are listed at approximately 4 hours 20 minutes via Idaho Falls, 4 hours 32 minutes through Kalispell, and 4 hours 35 minutes through Spokane. These options involve airline combinations and availability can vary by date.

Since nonstop services are frequent on DEN–SEA, flying directly will normally keep the overall journey shorter. When comparing options, check the complete elapsed time, departure schedule and layover rather than judging an itinerary only by the individual flight segments.

Usual Nonstop Journey Length Between Denver and Seattle

Most direct Denver-to-Seattle flights take about three hours.
Current schedules list approximately 3 hours with United Airlines and Southwest Airlines, 3 hours 1 minute with Alaska Airlines, 3 hours 6 minutes with Frontier Airlines and 3 hours 11 minutes with Delta Air Lines on representative nonstop services. Southwest separately reports an average flight time of 2 hours 58 minutes.

A nonstop flight between Denver International Airport (DEN) and Seattle-Tacoma International Airport (SEA) typically takes around 3 hours to 3 hours 11 minutes, depending on the carrier and individual schedule.

The two airports are separated by roughly 1,020 miles (1,640 km). FlightConnections gives the distance as 1,021 miles (1,643 km), while other route databases calculate a slightly different figure, so the mileage is best treated as approximate.

Nonstop service is currently provided by Alaska Airlines, Delta Air Lines, Frontier Airlines, Southwest Airlines and United Airlines.

FlightsFrom shows multiple daily departures with several of these carriers.

For passengers mainly concerned with reducing travel time, a direct DEN–SEA flight is normally the simplest choice because it removes the need to change aircraft along the way.

One possible indirect routing connects through Idaho Falls Regional Airport (IDA).

Current route listings show some DEN–IDA–SEA combinations taking approximately 4 hours 20 minutes overall. These itineraries can combine United Airlines and Alaska Airlines services.

This makes Idaho Falls one of the shorter one-stop alternatives currently listed between Denver and Seattle.

Even so, the journey adds more than an hour compared with many nonstop options, so travelers should check whether the connection offers a meaningful advantage in price or departure time.

Another possible route involves a transfer at Glacier Park International Airport (FCA) near Kalispell.
Certain DEN–FCA–SEA itineraries are listed at approximately 4 hours 32 minutes in total.

Travelers may also connect through Spokane International Airport (GEG). Some DEN–GEG–SEA combinations take approximately 4 hours 35 minutes, depending on the available flights.

These connecting journeys can involve United Airlines and Alaska Airlines. The total duration changes according to the specific departure and the waiting time between flights.

Passengers who do not choose a nonstop flight can find several alternative connecting routes.

Published schedules include transfer possibilities through Idaho Falls, Kalispell, Spokane, Redmond, Portland, Salt Lake City, Medford, Pasco, Bozeman, Missoula, Las Vegas and other western U.S. airports.

Some representative journey times include:

DEN–IDA–SEA: around 4 hrs 20 mins
DEN–FCA–SEA: around 4 hrs 32 mins
DEN–GEG–SEA: around 4 hrs 35 mins
DEN–RDM–SEA: around 4 hrs 38 mins
DEN–PDX–SEA: around 4 hrs 50 mins on some Alaska itineraries
DEN–SLC–SEA: around 4 hrs 59 mins on some Delta itineraries

These times represent particular published route combinations rather than fixed durations for every flight.

For connecting travel, layover length can make a substantial difference to the complete journey. A short connection may keep the trip below five hours, while another itinerary using the same airport could take much longer.

Denver to Seattle Travel Time by Route

Departure Airport	Arrival Airport	Route Code	Estimated Flight Time
Denver International Airport (DEN)	Seattle-Tacoma International Airport (SEA)	DEN–SEA	Around 3 hrs–3 hrs 11 mins nonstop
Denver International Airport (DEN)	Seattle-Tacoma International Airport (SEA)	DEN–IDA–SEA	Around 4 hrs 20 mins with one stop
Denver International Airport (DEN)	Seattle-Tacoma International Airport (SEA)	DEN–FCA–SEA	Around 4 hrs 32 mins with one stop
Denver International Airport (DEN)	Seattle-Tacoma International Airport (SEA)	DEN–GEG–SEA	Around 4 hrs 35 mins with one stop
Denver International Airport (DEN)	Seattle-Tacoma International Airport (SEA)	DEN–RDM–SEA	Around 4 hrs 38 mins with one stop
Denver International Airport (DEN)	Seattle-Tacoma International Airport (SEA)	DEN–PDX–SEA	Around 4 hrs 50 mins with one stop
Denver International Airport (DEN)	Seattle-Tacoma International Airport (SEA)	DEN–SLC–SEA	Around 4 hrs 59 mins with one stop

Current route information places the quickest nonstop journey at about three hours, while the faster one-stop combinations begin at approximately 4 hours 20 minutes.
The figures above are planning estimates rather than guaranteed arrival times. Weather, winds, air-traffic conditions, airport delays and the amount of time between connecting flights

Which Airlines Currently Fly Nonstop from Denver to Seattle?

United Airlines

Alaska Airlines

Delta Air Lines

Southwest Airlines

Frontier Airlines

How Does Seattle's Local Time Compare with Denver?

Seattle is one hour behind Denver.
Denver follows the Mountain Time Zone, while Seattle observes Pacific Time. During daylight saving time, Denver uses MDT at UTC−6 and Seattle uses PDT at UTC−7, maintaining a one-hour difference.

For example, when it is 3:00 PM in Denver, it is 2:00 PM in Seattle.

Both cities generally move between standard time and daylight saving time according to the same U.S. schedule, so the one-hour difference normally remains unchanged throughout the year.

The time-zone shift also affects how a flight looks on an itinerary. A journey lasting about three hours may appear to arrive only around two hours after departure when comparing the local clock times because Seattle is already one hour behind Denver.

Explore More Flight Times & Routes

Planning beyond this route? Explore more flight times, distances, and travel durations using our tools below.

Start with our Flight Time Calculator to estimate journey times worldwide, or browse average travel times from your departure city using the Denver Flight Times.