Distance between cities › USA › Montana › Boulder, MT › Distance from Boulder to Portland International Airport Book Hotels

Distance from Boulder, MT to PDX Airport

Distance

688 mi

Time

12 hours 30 mins

Gas Cost

$65 - $126

Helpful Inaccurate

There are 505.11 miles from Boulder to Portland International Airport (PDX) in west direction and 688 miles (1,107.23 kilometers) by car, following the US-12 route.

Boulder and PDX Airport are 12 hours 30 mins far apart, if you drive non-stop .

This is the fastest route from Boulder, MT to PDX Airport. The halfway point is Spokane, WA.

Please note the time difference between Boulder, MT and PDX Airport is 1 hour. The current time in Boulder is 1:35 am and the current time in PDX Airport is 12:35 am.

Any questions or tips to share?

Share with fellow travellers any question or tips about the route from Boulder, MT to PDX Airport:

Lowest Price Rental Cars in Boulder, MT

Planning on renting a car to go from Boulder, MT to PDX Airport? Here there are some offers to rent a car in Boulder, MT

Small

From $14

Intermediate

From $18

Full-size

From $24

SUVs

From $28

Vans

From $40

Compare rental car prices in Boulder »

Gas Consumption and Emissions

A car with a fuel efficiency of MPG will need 27.64 gallons of gas to cover the route between Boulder, MT and PDX Airport.

The estimated cost of gas to go from Boulder to PDX Airport is $90.97.

During the route, an average car will release 541.57 pounds of CO₂ to the atmosphere. The carbon footprint would be 0.79 pounds of CO₂ per mile.

Average USA gas price used for calculation is $3.29 per gallon of regular gas. Price last updated on March 13, 2026.
Read more about our CO₂ calculation.

Halfway Point Between Boulder, MT and PDX Airport

If you want to meet halfway between Boulder, MT and PDX Airport or just make a stop in the middle of your trip, the exact coordinates of the halfway point of this route are 47.652889 and -117.363663, or 47º 39' 10.4004" N, 117º 21' 49.1868" W. This location is 344.15 miles away from Boulder, MT and PDX Airport and it would take approximately 6 hours 15 mins to reach the halfway point from both locations.

Closest City or Town to Halfway Point

The closest and also the major city is Spokane, WA, situated 339.96 miles from Boulder, MT and 338.82 miles from PDX Airport. It would take 5 hours 1 min to go from Boulder to Spokane and 5 hours 22 mins to go from PDX to Spokane.