Distance between cities › USA › Idaho › Downey, ID › Distance from Downey to Roy Book Hotels

Distance from Downey, ID to Roy, MT

Distance

483 mi

Time

9 hours 43 mins

Gas Cost

$45 - $87

There are 372.55 miles from Downey to Roy in northeast direction and 483 miles (777.31 kilometers) by car, following the US-191 and US-287 route.

Downey and Roy are 9 hours 43 mins far apart, if you drive non-stop .

This is the fastest route from Downey, ID to Roy, MT. The halfway point is Big Sky, MT.

Downey, ID and Roy, MT are in the same time zone (MDT). Current time in both locations is 10:15 pm.

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Lowest Price Rental Cars in Downey, ID

Planning on renting a car to go from Downey, ID to Roy, MT? Here there are some offers to rent a car in Downey, ID

Small

From $14

Intermediate

From $18

Full-size

From $24

SUVs

From $28

Vans

From $40

Compare rental car prices in Downey »

Gas Consumption and Emissions

A car with a fuel efficiency of MPG will need 19.39 gallons of gas to cover the route between Downey, ID and Roy, MT.

The estimated cost of gas to go from Downey to Roy is $63.25.

During the route, an average car will release 379.87 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 $3.26 per gallon of regular gas. Price last updated on March 12, 2026.
Read more about our CO₂ calculation.

Halfway Point Between Downey, ID and Roy, MT

If you want to meet halfway between Downey, ID and Roy, MT or just make a stop in the middle of your trip, the exact coordinates of the halfway point of this route are 45.337288 and -111.189590, or 45º 20' 14.2368" N, 111º 11' 22.524" W. This location is 241.39 miles away from Downey, ID and Roy, MT and it would take approximately 4 hours 51 mins to reach the halfway point from both locations.

Closest City or Town to Halfway Point

The closest town to the halfway point is Big Sky, MT, situated 247 miles from Downey, ID and 243 miles from Roy, MT. It would take 4 hours 22 mins to go from Downey to Big Sky and 5 hours 6 mins to go from Roy to Big Sky.