Flight time: Seattle to Denver

Route details

Distance breakdown: Seattle to Denver

The 1,645-km great-circle distance between Seattle (47.45°N, 122.31°W) and Denver (39.86°N, 104.67°W) spans 7.6° of latitude and 17.6° of longitude, trending primarily east. In miles, this is 1,022 mi or 888 nautical miles. The great-circle path — the shortest distance over Earth's curved surface — is calculated using the Haversine formula from the two airports' precise coordinates.

Cruise speed and flight phases

At 1,645 km, this medium-haul route falls in the operational sweet spot where aircraft reach cruise altitude for a meaningful portion of the flight. Effective cruise speeds of 780–850 km/h are typical, with narrow-body aircraft (A320neo, 737 MAX) handling the lower end and wide-body aircraft achieving speeds at the upper end. The 2h 26m to 2h 57m estimate accounts for approximately 20 minutes of combined climb and descent, with the remainder at efficient cruise altitude.

Ground time and routing overhead

Our 30–50 minutes overhead allowance covers: taxi-out at SEA, takeoff and initial climb, descent and approach at DEN, and taxi-in to the gate. SEA is a major international hub where taxi times of 15–25 minutes are common during peak periods. At DEN, arrival taxi and gate assignment can add 10–20 minutes, especially during busy arrival banks. Continental air traffic corridors between Seattle and Denver may add 3–8% beyond the great-circle distance. Standard instrument departures and arrivals at both airports use predefined routing that adds distance but ensures safe separation.

Return flight: Denver → Seattle

The return flight from Denver to Seattle is generally similar in duration to the outbound — typically within 10–20 minutes. Continental routes like this one are less affected by the jet stream asymmetry that makes oceanic east-west routes so uneven. The main variables affecting any difference are: prevailing winds at these latitudes (modest effect), different standard instrument departures/arrivals at each airport (minor effect), and air traffic congestion patterns that vary by time of day and direction.

Seasonal variation in flight times

Flight times between Seattle and Denver vary modestly by season — typically 10–20 minutes. Upper-level wind patterns shift with the seasons: winter generally brings stronger westerly winds at these latitudes, while summer patterns are more variable. Thunderstorm activity along the route corridor peaks in summer months, occasionally causing routing diversions that add distance. Winter operations may include de-icing delays at SEA, which extend the overall gate-to-gate time.

Airport information

Seattle-Tacoma International Airport (SEA) is a major international hub in Seattle, United States. As a tier-1 airport, it handles high traffic volumes, which means longer average taxi times but also higher flight frequency and competition that can benefit travelers on pricing. Denver International Airport (DEN) is a major international hub in Denver, United States. As a tier-1 airport, it handles high traffic volumes, which means longer average taxi times but also higher flight frequency and competition that can benefit travelers on pricing.

Flight times from Seattle to other destinations

Flight time FAQ: Seattle to Denver