How far is Boise, ID from Fremont County, ID?
The driving distance from Boise, ID to Fremont County, ID is about 345.9 miles (556.6 km), with a travel time of about 05h 54m by car.
- The straight-line flight distance is about 238.7 miles (384.2 km).
- For a round trip, plan for roughly 11h 48m 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 05h 54m.
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.
City in Cassia County, Idaho, United States
Route Weather Snapshot
Check the forecast at both ends before you head out.
Mostly Sunny
Sunny
Driving Route Map
The map below follows the saved road route between Boise and Fremont County.
Turn-by-Turn Driving Directions
Step-by-step road directions between Boise and Fremont County.
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1
Start on the route
36 m · 11 sec
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2
Turn right
80 m · 21 sec
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3
Turn right onto South 6th Street
849 ft · 39 sec · South 6th Street
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4
Turn left onto West Myrtle Street
1 km · 1 min · West Myrtle Street
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5
Turn right onto South Broadway Avenue
2.8 mi · 6 min · South Broadway Avenue
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6
Take the ramp left toward I 84 East
2049 ft · 46 sec · Idaho Medal of Honor Highway
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7
Continue on Vietnam Veterans Memorial Highway
166.5 mi · 2 hr 36 min · Vietnam Veterans Memorial Highway
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8
Continue straight
62.7 mi · 59 min
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9
Keep slight left to continue on Idaho Falls
3046 ft · 40 sec
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10
Merge slight right
46.3 mi · 44 min
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11
Take the exit slight right toward US 20 East, I 15: Rigby, West Yellowstone
1434 ft · 35 sec
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12
Continue on Rigby Highway
3.1 mi · 4 min · Rigby Highway
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13
Continue on Idaho Medal of Honor Highway
15.4 mi · 16 min · Idaho Medal of Honor Highway
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14
Continue on Yellowstone Highway
17.2 mi · 18 min · Yellowstone Highway
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15
Continue on Idaho Medal of Honor Highway
25.5 mi · 29 min · Idaho Medal of Honor Highway
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16
Turn left onto South Antelope Flat Road
4.3 mi · 17 min · South Antelope Flat Road
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17
Arrive at your destination
0 m · 1 sec · South Antelope Flat Road
Car Route Details
A richer read on the saved driving route between Boise and Fremont County.
Long-distance drive
This route is long enough that fuel, rest stops, weather, and timing matter more than any single maneuver.
Vietnam Veterans Memorial Highway
Continue on Vietnam Veterans Memorial Highway
166 mi · 02h 36m
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.
Mostly Sunny leaving Boise and Sunny near Fremont County.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from Boise to Fremont County?
The road trip is about 345.9 miles (556.6 km) and usually takes 05h 54m 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?
Declo is a useful midpoint, sitting about 172.7 miles from Boise and 173.2 miles from Fremont County.
How much longer is the road route than the straight-line distance?
The direct path is about 238.7 miles (384.2 km), while the road route adds roughly 107.2 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 5:12 AM MDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $47.49 one way or $94.99 round trip. Estimated CO2 is about 108.4 kg one way.
What should you check before leaving?
Before you leave, expect Mostly Sunny around Boise and Sunny near Fremont County.
Stop Ideas Near Declo
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 Declo.
Twin Falls, Idaho
Flight Path Map
This map shows the direct air route between Boise and Fremont County. Straight-line distance: 238.76 mi (384.24 km).
#1 Boise
The capital of Idaho.
| Population | 228,959 |
| Coordinates | 43.6135000, -116.2034500 |
| Altitude | 823 |
| Country | United States |
#2 Fremont County
County in Idaho, United States
| Population | 13,099 |
| Coordinates | 44.2287900, -111.4820200 |
| Altitude | 1892 |
| Country | United States |
End: Fremont County (-111.48202, 44.22879)
Estimated Travel Time
Distance: 557 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 11h 31m |
| 40 mph (64.37 km/h) | 08h 38m |
| 50 mph (80.47 km/h) | 06h 55m |
| 60 mph (96.56 km/h) | 05h 45m |
| 70 mph (112.65 km/h) | 04h 56m |
| 80 mph (129 km/h) | 04h 18m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.89 | $47.49 | $94.99 |
| Mid-grade | $4.23 | $51.62 | $103.24 |
| Premium | $4.55 | $55.50 | $111.00 |
| Diesel | $5.41 | $66.03 | $132.05 |
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 Idaho · 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.