Distance between cities › USA › South Dakota › Dewey, SD › Distance from Dewey to Riley Book Hotels

Distance from Dewey, SD to Riley, OR

Distance

1,124 mi

Time

20 hours 1 min

Gas Cost

$105 - $204

There are 773.40 miles from Dewey to Riley in west direction and 1,124 miles (1,808.90 kilometers) by car, following the I-80 and US-30 and WY 789 route.

Dewey and Riley are 20 hours 1 min far apart, if you drive non-stop .

This is the fastest route from Dewey, SD to Riley, OR. The halfway point is Evanston, WY.

Please note the time difference between Dewey, SD and Riley, OR is 1 hour. The current time in Dewey is 12:16 pm and the current time in Riley is 11:16 am.

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Lowest Price Rental Cars in Dewey, SD

Planning on renting a car to go from Dewey, SD to Riley, OR? Here there are some offers to rent a car in Dewey, SD

Small

From $14

Intermediate

From $18

Full-size

From $24

SUVs

From $28

Vans

From $40

Compare rental car prices in Dewey »

Gas Consumption and Emissions

A car with a fuel efficiency of MPG will need 45.16 gallons of gas to cover the route between Dewey, SD and Riley, OR.

The estimated cost of gas to go from Dewey to Riley is $147.31.

During the route, an average car will release 884.75 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 Dewey, SD and Riley, OR

If you want to meet halfway between Dewey, SD and Riley, OR or just make a stop in the middle of your trip, the exact coordinates of the halfway point of this route are 41.249569 and -111.058113, or 41º 14' 58.4484" N, 111º 3' 29.2068" W. This location is 562.22 miles away from Dewey, SD and Riley, OR and it would take approximately 10 hours to reach the halfway point from both locations.

Closest City or Town to Halfway Point

The closest town to the halfway point is Evanston, WY, situated 580 miles from Dewey, SD and 588 miles from Riley, OR. It would take 8 hours 21 mins to go from Dewey to Evanston and 9 hours 30 mins to go from Riley to Evanston.