Spanning 490.8 miles across the Mountain West, this trip from Idaho Falls to Post Falls takes approximately 7 hours and 27 minutes of active driving time. While it is technically feasible as a single-day journey, the duration makes for a long day behind the wheel. You should budget about $78 for fuel to cover the distance. Navigating this route involves a heavy reliance on local roads like South Boulevard, Stonebrook Lane, and West Stone Run Lane rather than major interstates. It is a straightforward trip if you prefer a slower, more deliberate pace through Idaho’s interior.
Trip Pace
Best split across 2 days
Treat the return leg as its own travel day rather than an afterthought.
Break Rhythm
2 planned breaks
Plan on a short reset every 3 to 4 hours to stay fresh behind the wheel.
Midpoint
244.3 miles from Idaho Falls, ID
A natural place for your longest stop of the day
, about 3h 57m into the drive
.
Main Roads
Road
Distance
Duration
I 90
285.8 mi
4h 49m
Veterans Memorial Highway
198.2 mi
3h 6m
South Boulevard
1 mi
2m
South Utah Avenue
0.7 mi
1m
East 17th Street
0.6 mi
<1m
Pancheri Drive
0.4 mi
<1m
North Spokane Street
0.3 mi
1m
West Broadway Street
0.3 mi
<1m
Longest stretch:
I 90
— 285.8 mi, about 4h 49m
Turn-by-Turn Driving Directions
Step-by-step road directions between Idaho Falls, ID and Post Falls, ID.
1
Start on Charleston Lane
152 ft·8 sec·Charleston Lane
2
Turn right onto West Stone Run Lane
241 ft·15 sec·West Stone Run Lane
3
Turn left onto Stonebrook Lane
466 ft·14 sec·Stonebrook Lane
4
Continue on South Boulevard
1.0 mi·2 min·South Boulevard
5
Turn left onto East 17th Street
0.6 mi·52 sec·East 17th Street
6
Continue on Pancheri Drive
0.4 mi·47 sec·Pancheri Drive
7
Turn right onto South Utah Avenue
0.1 mi·15 sec·South Utah Avenue
8
Enter roundabout onto South Utah Avenue
222 ft·4 sec·South Utah Avenue
9
Continue on South Utah Avenue
0.5 mi·58 sec·South Utah Avenue
10
Turn left onto I 15 BUS; US 20 BUS
0.3 mi·34 sec·West Broadway Street
11
Take the ramp onto I 15 BUS; US 20
0.2 mi·27 sec·I 15 BUS; US 20
Exit 118Toward I15 North: Roberts, Butte
12
Merge onto I 15; US 20
198 mi·3 hr 6 min·Veterans Memorial Highway
13
Take the exit
0.5 mi·1 min
Toward I 90 West: Missoula
14
Merge onto I 90
286 mi·4 hr 49 min·I 90
Toward I 90 West: Missoula
15
Take the exit
0.4 mi·50 sec
Toward Spokane Street
16
Turn right onto I 90 Bus
0.3 mi·1 min·North Spokane Street
17
Turn left onto West 10th Avenue
0.2 mi·38 sec·West 10th Avenue
18
Arrive at destination
West 10th Avenue
Trip Plan
To manage the 7-hour and 27-minute duration effectively, plan for at least 2 scheduled stops to break up the intensity of the turn-heavy local roads. Departing early in the morning is your best strategy to avoid fatigue and ensure you reach Post Falls before dark. Since this route relies on local streets rather than interstates, keep a close eye on your GPS to navigate turns efficiently and stay on track. Budgeting $78 for fuel is a solid starting point, but keep a little extra set aside for potential fluctuations at local pumps along the way. Given the nature of this 490.8-mile drive, prioritize consistent hydration and regular stretching to stay alert behind the wheel.
Morning Departure
Start early — leave by 6-7 AM to arrive at a reasonable hour.
Evening Departure
This is a long drive — plan for a morning departure or consider splitting it into two days.
This drive is better paced as a 2-day trip.
Plan roughly 2 meaningful breaks for fuel, food, and rest.
The halfway point lands around 244.3 miles from Idaho Falls, ID, or about 3h 57m into the drive.
The longest continuous stretch on this route runs about 285.8 miles.
Consider an overnight stop or starting very early.
Departure
Before you leave
Start with fuel, water, and navigation already sorted so the first hour feels easy.
First stop
Around 107 miles or 1h 44m in
Use this first pause for coffee, a restroom break, and a quick traffic check ahead.
Halfway reset
Around 244.3 miles or 3h 57m in
This is the best place for your longest stop, a real meal, and a full fuel check.
Overnight split
Day 1 wrap after about 244.3 miles or 3h 57m
Stop before fatigue turns the last few hours into a grind. You want day two to start fresh, not just resumed.
Final approach
Final hour starts around 7h 4m
Traffic, exits, and arrival timing usually matter more near Post Falls, ID than in the middle of the route.
Before You Leave
+
Open the route before leaving Idaho Falls, ID so your first major turns are already loaded.
+
Leave with enough water and a charging cable within reach, not packed away.
+
Check your fuel range against the first long segment, especially if you are starting outside city service areas.
+
Pick one backup stop option before the midpoint in case traffic changes your pacing.
+
Treat this as a 2-day road trip and book the overnight stop before the busiest arrival window.
Day 1
Settle into the route from Idaho Falls, ID
Aim for roughly 244 miles and 4.1 hours of wheel time on this day.
Day 2
Finish the approach into Post Falls, ID
Aim for roughly 244 miles and 4.1 hours of wheel time on this day.
Your first comfortable stop window is around 107 miles from Idaho Falls, ID.
This route usually feels better as a 2-day drive than as one long push.
Plan about 2 real breaks rather than only quick fuel stops.
The longest stretch is on I 90 for about 285.8 miles.
Where to Stop
Rest stops, refuel points, and overnight suggestions along this route.
Place data sourced from public business listings. Hours and availability may vary.
Heads-up: tricky spots
5 of 13
5 decision points cluster between mile 0 and 3 — GPS handles the exact turns, but know they're coming. Your lane choice matters more than the turn itself.
5
0 mi into trip|~0m in|West Stone Run Lane
Turn right onto West Stone Run Lane
Navigation decision point
5
0.1 mi into trip|~0m in|Stonebrook Lane
Turn left onto Stonebrook Lane
Navigation decision point
4
1.1 mi into trip|~3m in|East 17th Street
Turn left onto East 17th Street
Navigation decision point
6
2.2 mi into trip|~5m in|South Utah Avenue
Enter roundabout onto South Utah Avenue
Roundabout - know your exit number before entering
7
3 mi into trip|~6m in|I 15 BUS; US 20
Take the ramp onto I 15 BUS; US 20 toward I15 North: Roberts, Butte
Multiple destination signs - pick the right one
Exit 118
Toward I15 North: Roberts, Butte
Fuel & Cost
Regular Gas
$77.43 one way
$154.85 round trip
$4.03/gal25.4 MPG avg171 kg CO2
Fuel Type
$/gal
One Way
Round Trip
midgrade
$4.22
$81.16
$162.32
premium
$4.53
$87.16
$174.32
diesel
$5.61
$107.88
$215.75
No toll roads detected on this route.
Estimated Trip Cost (one way, 1 person)
Fuel
$77
Hotel (1n)
$80–$140
Meals
$50–$100
Total
$207–$317
Rough estimate based on US averages. Hotel $80–$140/night, meals $25–$50/day.
Estimated CO2 emission: 171 kg one way.
Prices: EIA weekly data, 2026-04-13.
Driving Electric?
About $51 in charging
· 1 stop
· 67% less CO2
Vehicle Type
kWh
Stops
DC Fast
Home Charge
Average EV
146.6
1
$51.30
$23.45
Efficient EV
122.2
1
$42.75
$19.54
EV Truck/SUV
195.4
2
$68.40
$31.27
Gas CO2
171 kg
EV CO2
57 kg (67% less)
Plan for 1 charging stop. A 30-minute DC fast charge mid-route should be enough to complete the trip comfortably.
DC fast charging avg $0.35/kWh. Home charging avg $0.16/kWh. US grid CO2: 0.39 kg/kWh.
Travel Intel
Current conditions at both ends of the drive.
Forecast as of Apr 15, 2026
Origin
Idaho Falls, ID
Evening
in Idaho Falls on Saturday
Local time
7:08 PM
MDT
Current temp
63°F
Unavailable
Live forecast
Destination
Post Falls, ID
Evening
in Post Falls on Saturday
Local time
6:08 PM
PDT
Current temp
45°F
Unavailable
Live forecast
Seasonal Notes
Summer travel usually means heavier construction, hotter rest stops, and busier weekend traffic around major cities.
Winter travel shortens daylight, so a route that looks manageable on paper can feel much longer after dark.
Holiday weekends tend to make both departure and arrival windows slower than the raw route time suggests.
For long drives, weather on day two can matter just as much as conditions at departure, so check the whole travel window rather than only the first day.
Time zone
1 hour earlier
The destination clock does not match departure time, so double-check hotel check-in windows and late arrival plans.
Temperature spread
18 degrees cooler at arrival
A meaningful temperature swing is a good cue to rethink layers, water, and how soon you want to arrive.
Road read
8h 6m on the road
This is long enough that the arrival forecast matters almost as much as departure conditions. Recheck both ends before you roll.
Weather data from the National Weather Service. Conditions may change; check closer to your travel date.
More Details
What kind of drive is this?
Expect a turn-heavy local drive that demands your full attention, as this route contains 0% highway travel. Because you are avoiding major high-speed corridors, the journey feels more like an extended series of local connections than a standard interstate cruise. The road profile is consistently technical, requiring frequent adjustments rather than long, uninterrupted stretches of cruising. You will navigate through varied local terrain, making the drive feel intimate and grounded in the regional landscape. Prepare for a steady, hands-on experience that deviates significantly from the typical high-speed transit found on major US highways.
59% highway, the rest on surface roads — varied driving throughout.
18 navigation steps total — most of the decisions cluster near the start and finish.
Longest single stretch: 285.8 mi on I 90.
How Hard Is This Drive?
4/10
This route mixes highway mileage with some local-road sections near the start or finish. There are only a few real navigation decisions along the way. The trickiest moment comes early in the drive near West Stone Run Lane.
Driving Effort4/10
Easy - simple navigation with a manageable amount of wheel time
Balances navigation complexity with total wheel time.
The route itself is not hard, but at 8h 6m, endurance matters. Plan breaks every 2-3 hours. The 13 decision points are all manageable with basic attention.
Where does it get tricky?
The main spots that need attention: near the start (West Stone Run Lane): Navigation decision point; at 0.1 miles (Stonebrook Lane): Navigation decision point; at 1.1 miles (East 17th Street): Navigation decision point.
Who Is This Route For?
Family Friendly
Moderate complexity with 2 natural rest stops along the way.
The longest stretch is about 285.8 miles on I 90. The full list of main roads is in the Roads section above.
Yes — a 2-day pace is more comfortable than one long haul. A sensible stopping point is after roughly 244 miles on day one.
We did not find dedicated rest areas on this route. For a drive this long, plan bathroom and stretch breaks around gas stations, fast-food stops, or small-town downtowns — check the Nearby Places section for options.
It helps. This is a long drive, so arriving tired and in the dark compounds. If the last hour of the trip is on surface roads or mountain grades, aim to arrive at Post Falls, ID before sunset when you can. Check the Trip Plan for departure windows that land you in daylight.
Only with planning. This is a long drive for kids — consider splitting it into two days rather than pushing through. Plan at least 2 meaningful breaks. Dedicated rest areas are limited, so plan gas or food stops as your bathroom breaks.
Mostly yes along the main roads, but rural stretches through ID can have sparse or no coverage. Before you leave, download offline Google Maps or Apple Maps for the route, and consider downloading music or podcasts instead of streaming. If you depend on data for navigation, keep a paper backup of the turn-by-turn directions.
The main spots that need attention: near the start (West Stone Run Lane): Navigation decision point; at 0.1 miles (Stonebrook Lane): Navigation decision point; at 1.1 miles (East 17th Street): Navigation decision point.
Not recommended in a single day. At 8.1 hours each way, a round trip means 16.2 hours of driving — that is an unsafe level of fatigue for most drivers. Plan at least one night at Post Falls, ID before the return drive.
