Grand Mound, WA to Spokane Valley, WA is 346.5 miles and takes about 6h 32m via I 90 and I 5, with a fuel budget near $73 and enough daylight to finish in a day. This trip covers ground across Washington, starting near the Pacific Coast and ending in the eastern part of the state. With 99% highway driving, expect a straightforward, efficient trip. This route is best suited for a single day of driving, making it a practical option for moving between regions or for a quick visit.
Trip Pace
Same-day drive is realistic
A same-day return is possible, but it will make for a full day on the road.
Break Rhythm
1 planned break
Plan on a short reset every 3 to 4 hours to stay fresh behind the wheel.
Midpoint
173.3 miles from Grand Mound, WA
A natural place for your longest stop of the day
, about 3h 22m into the drive
.
Main Roads
Road
Distance
Duration
I 90
263.1 mi
4h 46m
I 5
53.1 mi
1h 3m
State Route 18
27.3 mi
34m
Old Highway 99 Southwest
1 mi
1m
US 12 West
0.3 mi
<1m
Snoqualmie Parkway
0.1 mi
<1m
North Pines Road
<0.1 mi
<1m
Longest stretch:
I 90
— 263.1 mi, about 4h 46m
Turn-by-Turn Driving Directions
Step-by-step road directions between Grand Mound, WA and Spokane Valley, WA.
1
Start on this road
292 ft·26 sec·this road
2
Turn left
99 ft·9 sec
3
Turn right onto Old Highway 99 Southwest
0.8 mi·1 min·Old Highway 99 Southwest
4
Enter roundabout onto Old Highway 99 Southwest
82 ft·4 sec·Old Highway 99 Southwest
5
Continue on Old Highway 99 Southwest
0.1 mi·17 sec·Old Highway 99 Southwest
6
Turn right onto US 12
0.3 mi·48 sec·US 12 West
Use the right lane.
7
Take the ramp
0.2 mi·24 sec
Toward I 5 North
8
Merge onto I 5
45 mi·53 min·I 5
Use the straight / slight right lanes.
9
Keep slight right at fork onto I 5
8.2 mi·10 min·I 5
Use the slight right lane.
10
Take the exit
0.5 mi·1 min
Exit 142AToward WA 18 East: Auburn, Muckleshoot ReservationUse the straight / slight right lanes.
11
Merge onto WA 18
27 mi·34 min·State Route 18
Use the straight / slight right lanes.
12
Continue on WA 18
0.1 mi·8 sec·Snoqualmie Parkway
13
Take the exit
0.6 mi·1 min
Toward I 90 East: Spokane
14
Merge onto I 90
252 mi·4 hr 32 min·I 90
Use the straight / slight right lanes.
15
Merge onto I 90; US 2; US 395
11 mi·14 min·I 90; US 2; US 395
16
Take the exit
0.4 mi·51 sec
Toward WA 27
17
Turn left onto WA 27
148 ft·11 sec·North Pines Road
Use the straight / left lanes.
18
Arrive at destination
WA 27
Trip Plan
Given the 6h 32m estimated drive time, starting early from Grand Mound is advisable to maximize daylight. The longest stretch without exits is over 260 miles on I 90, so ensure you have adequate fuel before beginning this segment. Plan for one main stop to stretch your legs and refuel, as the drive is manageable in a single day. The fuel cost is estimated at $73, so factor this into your budget. Keep an eye on traffic conditions, especially around major population centers, although this route is predominantly rural.
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.
You can normally do this drive in one day.
Plan roughly 1 meaningful break for fuel, food, and rest.
The halfway point lands around 173.3 miles from Grand Mound, WA, or about 3h 22m into the drive.
The longest continuous stretch on this route runs about 263.1 miles.
This is a comfortable same-day trip.
Departure
Before you leave
Start with fuel, water, and navigation already sorted so the first hour feels easy.
First stop
Around 76 miles or 1h 35m in
Use this first pause for coffee, a restroom break, and a quick traffic check ahead.
Halfway reset
Around 173.3 miles or 3h 22m in
This is the best place for your longest stop, a real meal, and a full fuel check.
Final approach
Final hour starts around 5h 25m
Traffic, exits, and arrival timing usually matter more near Spokane Valley, WA than in the middle of the route.
Before You Leave
+
Open the route before leaving Grand Mound, WA 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.
Day 1
Settle into the route from Grand Mound, WA
This is one driving day of about 346.5 miles and 6h 32m.
Your first comfortable stop window is around 76 miles from Grand Mound, WA.
This route can stay practical as a one-day drive if traffic stays reasonable.
Plan about 1 real break rather than only quick fuel stops.
The longest stretch is on I 90 for about 263.1 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 14
5 decision points cluster between mile 0.1 and 54.6 — GPS handles the exact turns, but know they're coming. Your lane choice matters more than the turn itself.
5
0.1 mi into trip|~0m in
Turn left
Navigation decision point
5
1 mi into trip|~2m in|US 12 / US 12 West
Turn right onto US 12 / US 12 West
Lane positioning matters here
Use the right lane.
5
1.4 mi into trip|~3m in
Take the ramp toward I 5 North
Navigation decision point
Toward I 5 North
6
46.4 mi into trip|~57m in|I 5
Keep slight right at fork onto I 5
Highway fork - watch signs carefully. Lane positioning matters here
Use the slight right lane.
8
54.6 mi into trip|~1h 7m in
Take the exit toward WA 18 East: Auburn, Muckleshoot Reservation
Exit ramp - move to the correct lane early. Lane positioning matters here. Multiple destination signs - pick the right one
Use the straight / slight right lanes.
Exit 142A
Toward WA 18 East: Auburn, Muckleshoot Reservat...
Fuel & Cost
Regular Gas
$72.52 one way
$145.04 round trip
$5.32/gal25.4 MPG avg121 kg CO2
Fuel Type
$/gal
One Way
Round Trip
midgrade
$5.58
$76.05
$152.11
premium
$5.77
$78.69
$157.37
diesel
$5.61
$76.50
$153.01
No toll roads detected on this route.
Estimated Trip Cost (one way, 1 person)
Fuel
$73
Meals
$25–$50
Total
$98–$123
Rough estimate based on US averages. Hotel $80–$140/night, meals $25–$50/day.
Estimated CO2 emission: 121.2 kg one way.
Prices: EIA weekly data, 2026-04-13.
Driving Electric?
About $36 in charging
· 1 stop
· 66% less CO2
Vehicle Type
kWh
Stops
DC Fast
Home Charge
Average EV
104
1
$36.38
$16.63
Efficient EV
86.6
0
$30.32
$13.86
EV Truck/SUV
138.6
1
$48.51
$22.18
Gas CO2
121 kg
EV CO2
41 kg (66% 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 20, 2026
Origin
Grand Mound, WA
Late night
in Grand Mound on Tuesday
Local time
4:48 AM
PDT
Current temp
67°F
Unavailable
Live forecast
Destination
Spokane Valley, WA
Late night
in Spokane Valley on Tuesday
Local time
4:48 AM
PDT
Current temp
77°F
Partly Sunny
E 2 mph1% chanceLive forecast
Flood Warning
Flood Warning issued April 20 at 9:24AM PDT by NWS Spokane WA
67°F
Monroe, WA
173 mi in
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.
Time zone
Same local time
Origin and destination are on the same clock, so arrival timing is easier to judge at a glance.
Temperature spread
10 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
6h 32m on the road
Start early — leave by 6-7 AM to arrive at a reasonable hour.
Weather data from the National Weather Service. Conditions may change; check closer to your travel date.
National Parks Near This Route
Worth a detour if your schedule allows.
Klondike Gold Rush - Seattle Unit National Historical Park
National Historical Park
Seattle flourished during and after the Klondike Gold Rush. Merchants supplied people from around the world passing through this port city on their way to a remarkable adventure in the Yukon Territory...
19 mi from route
~48 min detour
Free
near mile 71.7
Park data from the National Park Service API. Alerts update every 2 hours.
More Details
What kind of drive is this?
This drive is almost entirely highway, with 99% of the 346.5 miles on major routes like I 90 and I 5. You'll encounter a significant stretch of 263.1 miles on I 90 without needing to exit. Expect mostly highway cruising, with the final segment likely transitioning to surface roads as you approach Spokane Valley.
99% highway — fuel and pacing are the main things to plan.
18 navigation steps total — most of the decisions cluster near the start and finish.
Longest single stretch: 263.1 mi on I 90.
How Hard Is This Drive?
8/10
This is a straightforward highway drive that stays mostly on I 90 and I 5. This route has several spots where lane changes, forks, or exits need your full attention. The trickiest moment comes around 0.1 miles in.
Driving Effort8/10
Demanding - plan breaks and stay ahead of the key maneuvers
Balances navigation complexity with total wheel time.
This is a demanding drive. With 14 significant decision points across 346.5 miles, you will need to stay alert - especially through interchange areas and urban stretches. Consider splitting it into segments if you are not comfortable with fast highway navigation.
Where does it get tricky?
The main spots that need attention: at 0.1 miles: Navigation decision point; at 1 miles (US 12 / US 12 West): Lane positioning matters here; at 1.4 miles: Navigation decision point.
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 Grand Mound, WA to Spokane Valley, WA, road signs begin pointing toward Muckleshoot Reservation along the way.
Muckleshoot Reservation
54.6 mi in|~1h 7m
Who Is This Route For?
Weekend Trip
Doable as a same-day drive at 6h 32m. Total distance: 346.5 miles.
Family Friendly
Moderate complexity with 1 natural rest stops along the way.
Solo Traveler
6h 32m drive, plan rest stops for pacing.
Frequently Asked Questions
The longest stretch is about 263.1 miles on I 90. The full list of main roads is in the Roads section above.
Yes — we found about 27 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 route has a higher-than-average number of complex decision points, which get harder in the dark. If the last hour of the trip is on surface roads or mountain grades, aim to arrive at Spokane Valley, WA 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 1 meaningful breaks. There are 27 rest areas along the route for bathroom stops.
The main spots that need attention: at 0.1 miles: Navigation decision point; at 1 miles (US 12 / US 12 West): Lane positioning matters here; at 1.4 miles: Navigation decision point.
Yes — Klondike Gold Rush - Seattle Unit National Historical Park. See the National Parks section for detour distances and tips on detours.
Not recommended in a single day. At 6.5 hours each way, a round trip means 13.1 hours of driving — that is an unsafe level of fatigue for most drivers. Plan at least one night at Spokane Valley, WA before the return drive.
