How far is O'Fallon, MO from Mountain Grove, MO?
The driving distance from O'Fallon, MO to Mountain Grove, MO is about 176.7 miles (284.3 km), with a travel time of about 03h 42m by car.
- The straight-line flight distance is about 144 miles (231.7 km).
- For a round trip, plan for roughly 07h 24m of driving time before adding stops, traffic, or weather delays.
- A comfortable departure window is usually 6:00 AM to 8:00 AM CDT.
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 03h 42m.
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 Phelps County, Missouri, United States
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 O'Fallon and Mountain Grove.
Turn-by-Turn Driving Directions
Step-by-step road directions between O'Fallon and Mountain Grove.
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1
Start on the route
8 m · 7 sec
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2
Turn left onto South Main Street
2865 ft · 1 min · South Main Street
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3
Continue straight
3.1 mi · 6 min
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4
Continue straight
3.4 mi · 5 min
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5
Take the ramp slight right toward I 64 East, US 40 East, US 61 South
1523 ft · 22 sec
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6
Merge slight left onto Avenue of the Saints
3.7 mi · 5 min · Avenue of the Saints
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7
Take the exit slight right toward Chesterfield Airport Road
2700 ft · 58 sec
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8
Continue on Chesterfield Airport Road
110 m · 7 sec · Chesterfield Airport Road
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9
Turn right onto Olive Street Road
64 m · 5 sec
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10
Turn right onto Olive Street Road
1.5 km · 2 min · Olive Street Road
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11
Continue on North Eatherton Road
2.4 mi · 5 min · North Eatherton Road
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12
Enter the roundabout and take exit 2 toward the route
21 m · 1 sec
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13
Exit the roundabout
4.3 mi · 7 min
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14
Enter the roundabout and take exit 2 toward the route
29 m · 2 sec
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15
Exit the roundabout
2098 ft · 45 sec
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16
Enter the roundabout and take exit 2 toward MO 100 West: Gray Summit
23 m · 2 sec
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17
Exit the roundabout onto MO 100 West: Gray Summit
1202 ft · 33 sec
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18
Merge slight left
13.3 mi · 19 min
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19
Take the exit slight right toward I 44 West, US 50 West: St. Clair
1157 ft · 14 sec
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20
Merge slight left
67.3 mi · 1 hr 12 min
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21
Take the exit slight right toward MO E: Rolla
910 ft · 19 sec
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22
Enter the roundabout and take exit 4 toward Tim Bradley Way
90 m · 6 sec · Tim Bradley Way
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23
Exit the roundabout onto Tim Bradley Way
2010 ft · 49 sec · Tim Bradley Way
-
24
Turn slight right onto North Bishop Avenue
9 m · 1 sec · North Bishop Avenue
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25
Keep slight right to continue on North Bishop Avenue
44 m · 3 sec · North Bishop Avenue
-
26
Continue on North Bishop Avenue
64.3 mi · 1 hr 20 min · North Bishop Avenue
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27
Turn right
1.1 km · 1 min
-
28
Turn left onto South Elm Street
1028 ft · 21 sec · South Elm Street
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29
Continue on Peabody Avenue
1637 ft · 36 sec · Peabody Avenue
-
30
Take the ramp right toward US 60 West: Mountain Grove
857 ft · 21 sec
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31
Merge slight left
5.1 mi · 6 min
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32
Take the exit slight right toward US 60 Business, MO MM: Mountain Grove
1264 ft · 36 sec
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33
Turn left
4.3 mi · 7 min
-
34
Turn left onto North Main Street
31 m · 2 sec · North Main Street
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35
Arrive at your destination
0 m · 1 sec · North Main Street
Car Route Details
A richer read on the saved driving route between O'Fallon and Mountain Grove.
Interchange-aware route
The drive includes several ramps, exits, or merges, so checking the next few maneuvers before busy interchanges is useful.
I 44 West
Merge slight left
67.3 mi · 01h 12m
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.
Sunny leaving O'Fallon and Sunny near Mountain Grove.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from O'Fallon to Mountain Grove?
The road trip is about 176.7 miles (284.3 km) and usually takes 03h 42m 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?
Saint James is a useful midpoint, sitting about 88.4 miles from O'Fallon and 88.4 miles from Mountain Grove.
How much longer is the road route than the straight-line distance?
The direct path is about 144 miles (231.7 km), while the road route adds roughly 32.7 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 CDT. If you want a more comfortable same-day return, try to leave by 9:36 AM CDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $23.49 one way or $46.99 round trip. Estimated CO2 is about 55.4 kg one way.
What should you check before leaving?
Before you leave, expect Sunny around O'Fallon and Sunny near Mountain Grove.
Stop Ideas Near Saint James
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 Saint James.
Jefferson City
Hermann
Washington
Flight Path Map
This map shows the direct air route between O'Fallon and Mountain Grove. Straight-line distance: 143.97 mi (231.69 km).
#1 O'Fallon
The most populous city in St.
| Population | 89,769 |
| Coordinates | 38.8106100, -90.6998500 |
| Altitude | 165 |
| Country | United States |
#2 Mountain Grove
City in Missouri
| Population | 4,705 |
| Coordinates | 37.1306100, -92.2634900 |
| Altitude | 451 |
| Country | United States |
End: Mountain Grove (-92.26349, 37.13061)
Estimated Travel Time
Distance: 284 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 05h 53m |
| 40 mph (64.37 km/h) | 04h 25m |
| 50 mph (80.47 km/h) | 03h 32m |
| 60 mph (96.56 km/h) | 02h 56m |
| 70 mph (112.65 km/h) | 02h 31m |
| 80 mph (129 km/h) | 02h 12m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.77 | $23.49 | $46.99 |
| Mid-grade | $4.25 | $26.50 | $52.99 |
| Premium | $4.65 | $28.99 | $57.99 |
| Diesel | $5.30 | $33.04 | $66.09 |
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 Missouri · Apr 19, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.