Embark on a 607.4-mile journey from Heyburn, ID, to Post Falls, ID, that will take approximately 9 hours and 57 minutes to complete. This long-distance drive is primarily on major interstates, with 98% of the route utilizing highways like I-86 and I-90. Given the duration, it's best split over two days to avoid fatigue. Your estimated fuel cost for this trip is around $87. Both your origin and destination are within the Mountain West region, offering a consistent feel throughout the drive.
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
303.7 miles from Heyburn, ID
A natural place for your longest stop of the day
, about 4h 48m into the drive
.
Main Roads
Road
Distance
Duration
I 90
285.8 mi
4h 49m
I 15 BUS
244.5 mi
3h 49m
I 86
62.7 mi
59m
Vietnam Veterans Memorial Highway
10.3 mi
9m
I 84 Business
1.1 mi
1m
18th Street
0.7 mi
1m
North Spokane Street
0.3 mi
1m
ID 24
0.2 mi
<1m
Longest stretch:
I 90
— 285.8 mi, about 4h 49m
Traffic on I-90
Hour-of-day weekday pattern from 58 FHWA count stations on your route.
Peak
4 PM
~981 veh/hr typical
· worst 1,230
Quietest
2 AM
~52 veh/hr
Peak-to-quiet ratio
18.9×
busier at peak than in the quiet hours
12a6anoon6p11p
Averaged across 52 weeks of 2023 FHWA Travel Monitoring Analysis System data. Weekday hours only (Mon–Fri).
Turn-by-Turn Driving Directions
Step-by-step road directions between Heyburn, ID and Post Falls, ID.
1
Start on O Street
44 ft·6 sec·O Street
2
Turn left onto 18th Street
0.7 mi·1 min·18th Street
3
Turn left onto I 84 Business; US 30
0.6 mi·56 sec·I 84 Business; US 30
4
Continue on ID 24
0.2 mi·22 sec·ID 24
5
Take the ramp
0.2 mi·25 sec
6
Continue on I 84 Business; US 30
0.5 mi·1 min·I 84 Business; US 30
7
Merge onto I 84; US 30
10 mi·9 min·Vietnam Veterans Memorial Highway
8
Continue on I 86; US 30
63 mi·59 min·I 86; US 30
9
Keep slight left at fork
0.6 mi·40 sec
Toward Idaho Falls
10
Merge onto I 15 BUS
244 mi·3 hr 49 min·I 15 BUS
11
Take the exit
0.5 mi·1 min
Toward I 90 West: Missoula
12
Merge onto I 90
286 mi·4 hr 49 min·I 90
Toward I 90 West: Missoula
13
Take the exit
0.4 mi·50 sec
Toward Spokane Street
14
Turn right onto I 90 Bus
0.3 mi·1 min·North Spokane Street
15
Turn left onto West 10th Avenue
0.2 mi·38 sec·West 10th Avenue
16
Arrive at destination
West 10th Avenue
Trip Plan
To make the most of this 607.4-mile drive, plan to depart early to maximize daylight hours. With a total duration of nearly 10 hours, splitting the trip over two days is highly recommended, allowing for restful overnight stops. You'll have two designated stops for breaks and refueling, which should be strategically placed. Pay attention to the longest stretch of 285.8 miles on I-90; ensure you have adequate fuel before entering this segment to manage your $87 fuel budget effectively.
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 303.7 miles from Heyburn, ID, or about 4h 48m 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 134 miles or 2h 8m in
Use this first pause for coffee, a restroom break, and a quick traffic check ahead.
Halfway reset
Around 303.7 miles or 4h 48m 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 303.7 miles or 4h 48m
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 8h 55m
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 Heyburn, 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 Heyburn, ID
Aim for roughly 304 miles and 5 hours of wheel time on this day.
Day 2
Finish the approach into Post Falls, ID
Aim for roughly 304 miles and 5 hours of wheel time on this day.
Your first comfortable stop window is around 134 miles from Heyburn, 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 11
5 decision points cluster between mile 0 and 320.8 — GPS handles the exact turns, but know they're coming. Your lane choice matters more than the turn itself.
4
0 mi into trip|~0m in|18th Street
Turn left onto 18th Street
Navigation decision point
4
1.5 mi into trip|~3m in
Take the ramp
Navigation decision point
5
75.2 mi into trip|~1h 13m in
Keep slight left at fork toward Idaho Falls
Highway fork - watch signs carefully
Toward Idaho Falls
4
320.3 mi into trip|~5h 4m in
Take the exit toward I 90 West: Missoula
Exit ramp - move to the correct lane early
Toward I 90 West: Missoula
4
320.8 mi into trip|~5h 5m in|I 90
Merge onto I 90 toward I 90 West: Missoula
Merge point - match speed before joining
Toward I 90 West: Missoula
Fuel & Cost
Regular Gas
$94.67 one way
$189.35 round trip
$3.96/gal25.4 MPG avg213 kg CO2
Fuel Type
$/gal
One Way
Round Trip
midgrade
$4.17
$99.79
$199.58
premium
$4.47
$106.99
$213.98
diesel
$4.80
$114.69
$229.38
No toll roads detected on this route.
Estimated Trip Cost (one way, 1 person)
Fuel
$95
Hotel (1n)
$80–$140
Meals
$50–$100
Total
$225–$335
Rough estimate based on US averages. Hotel $80–$140/night, meals $25–$50/day.
Estimated CO2 emission: 212.5 kg one way.
Prices: EIA weekly data, 2026-07-13.
Driving Electric?
About $64 in charging
· 2 stops
· 67% less CO2
Vehicle Type
kWh
Stops
DC Fast
Home Charge
Average EV
182.2
2
$63.78
$29.16
Efficient EV
151.9
1
$53.15
$24.30
EV Truck/SUV
243
3
$85.04
$38.87
Gas CO2
213 kg
EV CO2
71 kg (67% less)
Plan for 2 charging stops, roughly every 270 miles. Allow 25-40 minutes per stop at a DC fast charger.
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 Jul 16, 2026
Origin
Heyburn, ID
Evening
in Heyburn on Saturday
Local time
7:29 PM
MDT
Current temp
94°F
Chance Showers And Thunderstorms
SSW 6 mph26% chanceLive forecast
Flash Flood Warning
Flash Flood Warning issued July 16 at 2:23PM MDT until July 16 at 5:30PM MDT by NWS Pocatello ID
Red Flag Warning
Red Flag Warning issued July 16 at 1:11PM MDT until July 16 at 9:00PM MDT by NWS Boise ID
Destination
Post Falls, ID
Evening
in Post Falls on Saturday
Local time
6:29 PM
PDT
Current temp
100°F
Slight Chance Showers And Thunderstorms
E 3 mph39% chanceLive forecast
Flash Flood Warning
Flash Flood Warning issued July 16 at 2:23PM MDT until July 16 at 5:30PM MDT by NWS Pocatello ID
Red Flag Warning
Red Flag Warning issued July 16 at 1:11PM MDT until July 16 at 9:00PM MDT by NWS Boise ID
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
6 degrees warmer at arrival
A meaningful temperature swing is a good cue to rethink layers, water, and how soon you want to arrive.
Road read
9h 57m 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 predominantly highway-focused experience on this route, with the vast majority of your travel occurring on interstates. You'll encounter a longest uninterrupted stretch of 285.8 miles on I-90, so be prepared for extended periods of consistent driving. The profile is best described as a long-distance drive, meaning the focus is on covering ground efficiently rather than frequent scenic detours. The road character remains largely consistent, making it a straightforward, albeit lengthy, interstate cruise.
98% highway — fuel and pacing are the main things to plan.
16 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 is a straightforward highway drive that stays mostly on I 90 and I 15 BUS. There are only a few real navigation decisions along the way. The trickiest moment comes early in the drive near 18th Street.
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 9h 57m, endurance matters. Plan breaks every 2-3 hours. The 11 decision points are all manageable with basic attention.
Where does it get tricky?
The main spots that need attention: near the start (18th Street): Navigation decision point; at 1.5 miles: Navigation decision point; at 75.2 miles: Highway fork - watch signs carefully.
Elevation Profile
High-altitude sections with notable climbs
6,176 ft2,179 ft
Total Climb
2,559 ft
Total Descent
4,532 ft
Highest Point
6,176 ft
~216.9 mi in
Elevation Range
3,997 ft
Notable High Points
6,176 ft at ~216.9 miles+869 ft prominence
5,618 ft at ~303.7 miles+465 ft prominence
Towns Mentioned on Route Signs
Based on OSRM destination-sign hints, not a full list of every settlement the road passes.
On the drive from Heyburn, ID to Post Falls, ID, road signs begin pointing toward Idaho Falls 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 304 miles on day one.
Yes — we found about 30 rest areas or service plazas within a short detour of the route (from OpenStreetMap). See the Rest Stops tab under Nearby Places for locations and mile markers. Plan to stretch, use the bathroom, and top off fluids every 2–3 hours on longer drives.
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. There are 30 rest areas along the route for bathroom stops.
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 (18th Street): Navigation decision point; at 1.5 miles: Navigation decision point; at 75.2 miles: Highway fork - watch signs carefully.
Not recommended in a single day. At 10.0 hours each way, a round trip means 19.9 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.
