Distance between cities › USA › South Dakota › Harrison, SD › Distance from Harrison to Great Falls Book Hotels

Distance from Harrison, SD to Great Falls, MT

Distance

809 mi

Time

14 hours 29 mins

Gas Cost

$75 - $147

There are 677.88 miles from Harrison to Great Falls in northwest direction and 809 miles (1,301.96 kilometers) by car, following the I-90 route.

Harrison and Great Falls are 14 hours 29 mins far apart, if you drive non-stop .

This is the fastest route from Harrison, SD to Great Falls, MT.

Please note the time difference between Harrison, SD and Great Falls, MT is 1 hour. The current time in Harrison is 3:37 am and the current time in Great Falls is 2:37 am.

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Lowest Price Rental Cars in Harrison, SD

Planning on renting a car to go from Harrison, SD to Great Falls, MT? Here there are some offers to rent a car in Harrison, SD

Small

From $14

Intermediate

From $18

Full-size

From $24

SUVs

From $28

Vans

From $40

Compare rental car prices in Harrison »

Gas Consumption and Emissions

A car with a fuel efficiency of MPG will need 32.49 gallons of gas to cover the route between Harrison, SD and Great Falls, MT.

The estimated cost of gas to go from Harrison to Great Falls is $105.98.

During the route, an average car will release 636.50 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 Harrison, SD and Great Falls, MT

If you want to meet halfway between Harrison, SD and Great Falls, MT or just make a stop in the middle of your trip, the exact coordinates of the halfway point of this route are 45.290555 and -105.071561, or 45º 17' 25.998" N, 105º 4' 17.6196" W. This location is 404.48 miles away from Harrison, SD and Great Falls, MT and it would take approximately 7 hours 14 mins to reach the halfway point from both locations.

Closest City or Town to Halfway Point

The closest town to the halfway point is Boyes, MT, situated 403 miles from Harrison, SD and 406 miles from Great Falls, MT. It would take 7 hours 1 min to go from Harrison to Boyes and 7 hours 28 mins to go from Great Falls to Boyes.