How long is the flight?

The flight is approximately 2 hours and 30 minutes.

Amtrak's California Zephyr serves Denver, but it is a long, scenic journey.

A car is recommended if you plan to explore the mountains outside Denver.

What is the best time to visit?

Summer for hiking and winter for skiing.

There are some toll roads in the Denver area, such as E-470.

Renton

Denver

Flight Driving

Renton to Denver

Updated: 28 May 2026

The distance from Renton to Denver is approximately 2,100 kilometers. Flying from Seattle-Tacoma International Airport to Denver International Airport is the most efficient method, taking about two and a half hours. Driving is a major journey, requiring 20 to 22 hours of driving time through Idaho, Utah, and Wyoming. Most travelers prefer flying to avoid the long drive across the Rockies. If you drive, be prepared for high-altitude driving and variable weather conditions.

Total Distance: 2,100 km driving distance, 1,650 km straight-line air distance.

Fastest Way

A direct flight from SEA to DEN is the fastest way to reach Denver.

Cheapest Way

Flying is generally the most cost-effective option when considering the time and fuel costs of driving.

Compare Renton to Denver Routes

	Flight Direct	Driving Direct
Duration	2 hours 30 mins	21 hours
Avg Price	$100-$250	$280-$400 in fuel
Operator	United Airlines	Personal Vehicle
Route	SEA to DEN	I-90 to I-80 through Montana and Wyoming.
Tip	The A-Line train connects Denver International Airport to downtown Union Station.	Be prepared for high winds and sudden snowstorms in Wyoming.

Travel Tips

Altitude
Denver is a mile high; drink plenty of water to help your body adjust to the altitude.
Weather
Mountain weather changes quickly; always dress in layers.
Airport Transit
The A-Line train is the most convenient way to get from the airport to downtown.
Sun Protection
The sun is stronger at higher altitudes; wear sunscreen.
Rental Cars
If you plan to visit the mountains, rent a vehicle with all-wheel drive.

Safety Tips

Mountain Driving
If driving, be cautious on mountain roads and check for winter storm warnings.
Hydration
Stay hydrated to prevent altitude sickness.
Emergency Prep
Keep a winter emergency kit in your car if you are driving in the mountains.
Sun Safety
Protect your skin from the intense mountain sun.