How far is Great Falls, MT from Dillon, MT?
The driving distance from Great Falls, MT to Dillon, MT is about 218.2 miles (351.1 km), with a travel time of about 03h 37m by car.
- The straight-line flight distance is about 170.2 miles (273.9 km).
- For a round trip, plan for roughly 07h 14m of driving time before adding stops, traffic, or weather delays.
- A comfortable departure window is usually 6:00 AM to 8:00 AM MDT.
Reverse, save, or send this route
This drive is better planned with a longer stop or an overnight stay. Copy the route link, send it to another device, or print a clean version before you head out.
This drive is better planned with a longer stop or an overnight stay.
Flight Distance
Driving Distance
Gas Cost Calculator
Leave and Arrive Planner
Pick a departure time to see your estimated arrival and same-day return window.
Drive time stays fixed at 03h 37m.
An early departure helps you fit a real stop into the day without turning the return into a late-night drive.
You are leaving earlier than the recommended window, which gives you extra margin for breaks and traffic.
Halfway Point
A useful midpoint for breaks, coffee, or meeting in the middle.
Town in Montana
Route Weather Snapshot
Check the forecast at both ends before you head out.
Snow Showers Likely
Snow Showers
Driving Route Map
The map below follows the saved road route between Great Falls and Dillon.
Turn-by-Turn Driving Directions
Step-by-step road directions between Great Falls and Dillon.
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1
Start on 4th Street South
49 m · 12 sec · 4th Street South
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2
Turn left onto 5th Avenue South
130 m · 21 sec · 5th Avenue South
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3
Turn right onto 5th Street South
1988 ft · 38 sec · 5th Street South
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4
Turn right onto 10th Avenue South
1.2 km · 1 min · 10th Avenue South
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5
Continue on Country Club Boulevard
1.3 mi · 2 min · Country Club Boulevard
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6
Keep slight left
1.2 km · 2 min
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7
Merge slight left onto First Special Service Force Memorial Highway
155.7 mi · 2 hr 33 min · First Special Service Force Memorial Highway
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8
Keep slight right to continue on I 15 South: Dillon, Idaho Falls
57.5 mi · 54 min
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9
Take the exit slight right toward I 15 Business, MT 41: Dillon, Twin Bridges
1.3 km · 2 min
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10
Turn right onto Black Tail Boulevard
2970 ft · 1 min · Black Tail Boulevard
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11
Continue on West Bannack Street
1489 ft · 43 sec · West Bannack Street
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12
Turn right onto South Idaho Street
107 m · 15 sec · South Idaho Street
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13
Arrive at your destination
0 m · 1 sec · South Idaho Street
Car Route Details
A richer read on the saved driving route between Great Falls and Dillon.
Highway-focused drive
Most of the mileage stays on named highways, so the important moments are ramps, exits, merges, and the final local approach.
First Special Service Force Memorial Highway
Merge slight left onto First Special Service Force Memorial Highway
156 mi · 02h 33m
Route Summary
A quick read on whether this route feels easy, ambitious, or worth planning around.
A longer out-and-back drive
This is still possible in one day, but it becomes a long driving day. Leaving early and planning your stop window matters more here.
Snow Showers Likely leaving Great Falls and Snow Showers near Dillon.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from Great Falls to Dillon?
The road trip is about 218.2 miles (351.1 km) and usually takes 03h 37m in normal driving conditions.
Is this a same-day trip or an overnight route?
This is still possible in one day, but it becomes a long driving day. Leaving early and planning your stop window matters more here.
What is the halfway point on this route?
Boulder is a useful midpoint, sitting about 109 miles from Great Falls and 109.2 miles from Dillon.
How much longer is the road route than the straight-line distance?
The direct path is about 170.2 miles (273.9 km), while the road route adds roughly 48 extra miles because roads do not follow the straight air line.
When is the best time to leave for this route?
A good departure window is usually 6:00 AM to 8:00 AM MDT. If you want a more comfortable same-day return, try to leave by 9:46 AM MDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $29.98 one way or $59.95 round trip. Estimated CO2 is about 68.4 kg one way.
What should you check before leaving?
Before you leave, expect Snow Showers Likely around Great Falls and Snow Showers near Dillon.
Stop Ideas Near Boulder
Useful break, food, and waypoint ideas within about 15 miles of the route midpoint.
Transit and Meeting Points
Useful pickup, handoff, or rendezvous points close to Boulder.
Butte, MT
Bozeman, MT
Flight Path Map
This map shows the direct air route between Great Falls and Dillon. Straight-line distance: 170.18 mi (273.88 km).
#1 Great Falls
Town in Cascade County, Montana, United States
| Population | 58,353 |
| Coordinates | 47.5002400, -111.3008100 |
| Altitude | 1015 |
| Country | United States |
#2 Dillon
City in Montana, United States
| Population | 4,333 |
| Coordinates | 45.2163100, -112.6375200 |
| Altitude | 1555 |
| Country | United States |
End: Dillon (-112.63752, 45.21631)
Estimated Travel Time
Distance: 351 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 07h 16m |
| 40 mph (64.37 km/h) | 05h 27m |
| 50 mph (80.47 km/h) | 04h 21m |
| 60 mph (96.56 km/h) | 03h 38m |
| 70 mph (112.65 km/h) | 03h 07m |
| 80 mph (129 km/h) | 02h 43m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.89 | $29.98 | $59.95 |
| Mid-grade | $4.23 | $32.58 | $65.16 |
| Premium | $4.55 | $35.03 | $70.05 |
| Diesel | $5.41 | $41.67 | $83.34 |
Assumes 8.3 L/100 km (about 28.3 MPG). CO2 is an estimate and varies by vehicle, fuel blend, traffic, and terrain.
Prices in Montana · Apr 16, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.