How far is Helena, MT from Boulder, MT?
The driving distance from Helena, MT to Boulder, MT is about 29.9 miles (48.1 km), with a travel time of about 00h 32m by car.
- The straight-line flight distance is about 24.9 miles (40.1 km).
- For a round trip, plan for roughly 01h 05m of driving time before adding stops, traffic, or weather delays.
- A comfortable departure window is usually 7:00 AM to 7:00 PM MDT.
Reverse, save, or send this route
This is an easy same-day return drive. Copy the route link, send it to another device, or print a clean version before you head out.
This is an easy same-day return drive.
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 00h 32m.
This is a short drive, so your comfort window is wide. Traffic and current weather matter more than the clock.
This departure sits inside the recommended comfort window for the route.
Halfway Point
A useful midpoint for breaks, coffee, or meeting in the middle.
Census designated place
Route Weather Snapshot
Check the forecast at both ends before you head out.
Sunny
Driving Route Map
The map below follows the saved road route between Helena and Boulder.
Turn-by-Turn Driving Directions
Step-by-step road directions between Helena and Boulder.
-
1
Start on Cruse Avenue
50 m · 8 sec · Cruse Avenue
-
2
Turn left onto 11th Avenue
1.4 mi · 4 min · 11th Avenue
-
3
Turn straight onto Prospect Avenue
835 ft · 22 sec · Prospect Avenue
-
4
Take the exit slight right toward I 15 South: Butte
1984 ft · 49 sec
-
5
Merge slight left onto First Special Service Force Memorial Highway
26.8 mi · 25 min · First Special Service Force Memorial Highway
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6
Take the exit slight right toward MT 69: Boulder
1242 ft · 37 sec
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7
Turn left
1.3 km · 1 min
-
8
Turn right onto West Centennial Avenue
112 m · 16 sec · West Centennial Avenue
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9
Arrive at your destination
0 m · 1 sec · West Centennial Avenue
Car Route Details
A richer read on the saved driving route between Helena and Boulder.
Turn-heavy local drive
The route has frequent decision points for its length, so lane choice and turn timing will matter more than cruising speed.
First Special Service Force Memorial Highway
Merge slight left onto First Special Service Force Memorial Highway
26.8 mi · 00h 25m
Route Summary
A quick read on whether this route feels easy, ambitious, or worth planning around.
A short regional drive
This route is short enough to handle as a quick errand, commute, or easy same-day return without much planning overhead.
Sunny leaving Helena and Sunny near Boulder.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from Helena to Boulder?
The road trip is about 29.9 miles (48.1 km) and usually takes 00h 32m in normal driving conditions.
Is this a same-day trip or an overnight route?
This route is short enough to handle as a quick errand, commute, or easy same-day return without much planning overhead.
What is the halfway point on this route?
Clancy is a useful midpoint, sitting about 14.9 miles from Helena and 15 miles from Boulder.
How much longer is the road route than the straight-line distance?
The direct path is about 24.9 miles (40.1 km), while the road route adds roughly 5 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 7:00 AM to 7:00 PM MDT. If you want a more comfortable same-day return, try to leave by 7:24 PM MDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $4.09 one way or $8.18 round trip. Estimated CO2 is about 9.3 kg one way.
What should you check before leaving?
Before you leave, expect Sunny around Helena and Sunny near Boulder.
Stop Ideas Near Clancy
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 Clancy.
Butte, MT
Bozeman, MT
Flight Path Map
This map shows the direct air route between Helena and Boulder. Straight-line distance: 24.94 mi (40.13 km).
#1 Helena
State capital of Montana, United States and seat of Lewis and Clark County
| Population | 33,737 |
| Coordinates | 46.5927100, -112.0361100 |
| Altitude | 1237 |
| Country | United States |
#2 Boulder
Town in Montana
| Population | 1,291 |
| Coordinates | 46.2365900, -112.1208300 |
| Altitude | 1496 |
| Country | United States |
End: Boulder (-112.12083, 46.23659)
Estimated Travel Time
Distance: 48 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 00h 59m |
| 40 mph (64.37 km/h) | 00h 44m |
| 50 mph (80.47 km/h) | 00h 35m |
| 60 mph (96.56 km/h) | 00h 29m |
| 70 mph (112.65 km/h) | 00h 25m |
| 80 mph (129 km/h) | 00h 22m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.89 | $4.09 | $8.18 |
| Mid-grade | $4.23 | $4.44 | $8.89 |
| Premium | $4.55 | $4.78 | $9.55 |
| Diesel | $5.41 | $5.68 | $11.37 |
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 18, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.