How far is Smithville, MO from O'Fallon, MO?
The driving distance from Smithville, MO to O'Fallon, MO is about 237.7 miles (382.6 km), with a travel time of about 03h 34m by car.
- The straight-line flight distance is about 211.9 miles (341 km).
- For a round trip, plan for roughly 07h 09m 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 34m.
An early departure helps you fit a real stop into the day without turning the return into a late-night drive.
This departure sits inside the recommended comfort window for the route.
Halfway Point
A useful midpoint for breaks, coffee, or meeting in the middle.
City in Cooper County, Missouri, USA
Route Weather Snapshot
Check the forecast at both ends before you head out.
Showers And Thunderstorms Likely
Mostly Sunny
Driving Route Map
The map below follows the saved road route between Smithville and O'Fallon.
Turn-by-Turn Driving Directions
Step-by-step road directions between Smithville and O'Fallon.
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1
Start on the route
21 m · 11 sec
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2
Turn left onto West Main Street
1042 ft · 41 sec · West Main Street
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3
Turn left
5.4 mi · 8 min
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4
Take the exit slight right toward I 435 East: Saint Louis
1534 ft · 53 sec
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5
Merge slight left
21.1 mi · 23 min
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6
Keep slight right to continue on I 70, US 24 West, US 40: Saint Louis, Kansas City, Sports Complex
1500 ft · 23 sec
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7
Keep slight left to continue on I 70 East: Saint Louis
1.2 mi · 2 min
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8
Keep slight left to continue on I 70 East: Saint Louis
143 m · 12 sec
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9
Merge slight left onto George Brett Super Highway
2213 ft · 29 sec · George Brett Super Highway
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10
Continue on Truman/Eisenhower Presidential Highway
2.9 mi · 3 min · Truman/Eisenhower Presidential Highway
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11
Continue on Clifton J. Scott Memorial Highway
1.8 mi · 2 min · Clifton J. Scott Memorial Highway
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12
Continue on Truman/Eisenhower Presidential Highway
2.6 mi · 3 min · Truman/Eisenhower Presidential Highway
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13
Continue on Dwight D. Eisenhower Highway
52.5 mi · 57 min · Dwight D. Eisenhower Highway
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14
Continue on U.S. Submarine Veterans' Memorial Highway
32 mi · 34 min · U.S. Submarine Veterans' Memorial Highway
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15
Keep slight left to continue on U.S. Submarine Veterans' Memorial Highway
22.4 mi · 24 min · U.S. Submarine Veterans' Memorial Highway
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16
Continue on Dwight D. Eisenhower Highway
1.8 mi · 2 min · Dwight D. Eisenhower Highway
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17
Continue on Highway Patrol Sgt. Benjamin Booth Memorial Highway
1.6 mi · 2 min · Highway Patrol Sgt. Benjamin Booth Memorial Highway
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18
Continue on Sheriff Roger I. Wilson Memorial Highway
1.9 mi · 2 min · Sheriff Roger I. Wilson Memorial Highway
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19
Continue on Dwight D. Eisenhower Highway
88.2 mi · 1 hr 44 min · Dwight D. Eisenhower Highway
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20
Take the exit slight right toward MO K: O'Fallon
1765 ft · 43 sec
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21
Turn straight onto Drennen Parkway
46 m · 3 sec · Drennen Parkway
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22
Keep slight right to continue on Drennen Parkway
51 m · 6 sec · Drennen Parkway
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23
Turn slight left onto MO K: O'Fallon
19 m · 3 sec
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24
Continue on South Main Street
3115 ft · 2 min · South Main Street
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25
Turn right
8 m · 2 sec
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26
Arrive at your destination
0 m · 1 sec
Car Route Details
A richer read on the saved driving route between Smithville and O'Fallon.
Highway-focused drive
Most of the mileage stays on named highways, so the important moments are ramps, exits, merges, and the final local approach.
Dwight D. Eisenhower Highway
Continue on Dwight D. Eisenhower Highway
88.2 mi · 01h 44m
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.
Showers And Thunderstorms Likely leaving Smithville and Mostly Sunny near O'Fallon.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from Smithville to O'Fallon?
The road trip is about 237.7 miles (382.6 km) and usually takes 03h 34m 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?
Boonville is a useful midpoint, sitting about 118.7 miles from Smithville and 119 miles from O'Fallon.
How much longer is the road route than the straight-line distance?
The direct path is about 211.9 miles (341 km), while the road route adds roughly 25.8 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 9:50 AM CDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $31.64 one way or $63.28 round trip. Estimated CO2 is about 74.6 kg one way.
What should you check before leaving?
Before you leave, expect Showers And Thunderstorms Likely around Smithville and Mostly Sunny near O'Fallon.
Stop Ideas Near Boonville
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 Boonville.
Sedalia
Jefferson City
Warrensburg
Hermann
Flight Path Map
This map shows the direct air route between Smithville and O'Fallon. Straight-line distance: 211.87 mi (340.97 km).
#1 Smithville
City in Tennessee
| Population | 11,011 |
| Coordinates | 39.3869400, -94.5810700 |
| Altitude | 248 |
| Country | United States |
#2 O'Fallon
The most populous city in St.
| Population | 89,769 |
| Coordinates | 38.8106100, -90.6998500 |
| Altitude | 165 |
| Country | United States |
End: (-90.699849, 38.810674)
Estimated Travel Time
Distance: 383 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 07h 55m |
| 40 mph (64.37 km/h) | 05h 56m |
| 50 mph (80.47 km/h) | 04h 45m |
| 60 mph (96.56 km/h) | 03h 57m |
| 70 mph (112.65 km/h) | 03h 23m |
| 80 mph (129 km/h) | 02h 57m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.77 | $31.64 | $63.28 |
| Mid-grade | $4.25 | $35.68 | $71.37 |
| Premium | $4.65 | $39.05 | $78.09 |
| Diesel | $5.30 | $44.50 | $89.00 |
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 23, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.