How far is Marion, MO from O'Fallon, MO?
The driving distance from Marion, MO to O'Fallon, MO is about 114.4 miles (184.1 km), with a travel time of about 01h 52m by car.
- The straight-line flight distance is about 90.2 miles (145.1 km).
- For a round trip, plan for roughly 03h 44m of driving time before adding stops, traffic, or weather delays.
- A comfortable departure window is usually 8:00 AM to 10:00 AM CDT.
Reverse, save, or send this route
This route works well as a day trip with time at the destination. Copy the route link, send it to another device, or print a clean version before you head out.
This route works well as a day trip with time at the destination.
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 01h 52m.
A morning start gives you useful time at the destination and keeps the return out of the late evening.
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 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 Marion and O'Fallon.
Turn-by-Turn Driving Directions
Step-by-step road directions between Marion and O'Fallon.
-
1
Start on the route
2.3 mi · 3 min
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2
Turn straight
9.8 mi · 14 min
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3
Turn left onto West Main Street
2.4 mi · 5 min · West Main Street
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4
Continue on West Main Street
1154 ft · 39 sec · West Main Street
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5
Take the ramp left toward US 54 East, US 63 North: Fulton, Columbia
122 m · 10 sec
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6
Merge slight left
29.4 mi · 32 min
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7
Take the exit slight right toward I 70 East, US 40 East: Saint Louis
1220 ft · 15 sec
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8
Merge slight left onto Dwight D. Eisenhower Highway
69.2 mi · 1 hr 20 min · Dwight D. Eisenhower Highway
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9
Take the exit slight right toward MO K: O'Fallon
1765 ft · 43 sec
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10
Turn straight onto Drennen Parkway
46 m · 3 sec · Drennen Parkway
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11
Keep slight right to continue on Drennen Parkway
51 m · 6 sec · Drennen Parkway
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12
Turn slight left onto MO K: O'Fallon
19 m · 3 sec
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13
Continue on South Main Street
3115 ft · 2 min · South Main Street
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14
Turn right
8 m · 2 sec
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15
Arrive at your destination
0 m · 1 sec
Car Route Details
A richer read on the saved driving route between Marion 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
Merge slight left onto Dwight D. Eisenhower Highway
69.2 mi · 01h 20m
Route Summary
A quick read on whether this route feels easy, ambitious, or worth planning around.
A comfortable day-trip route
This route works well as a day trip. You can leave in the morning, spend meaningful time at the destination, and still return the same day.
Sunny leaving Marion and Sunny near O'Fallon.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from Marion to O'Fallon?
The road trip is about 114.4 miles (184.1 km) and usually takes 01h 52m in normal driving conditions.
Is this a same-day trip or an overnight route?
This route works well as a day trip. You can leave in the morning, spend meaningful time at the destination, and still return the same day.
What is the halfway point on this route?
Montgomery City is a useful midpoint, sitting about 57.3 miles from Marion and 57.1 miles from O'Fallon.
How much longer is the road route than the straight-line distance?
The direct path is about 90.2 miles (145.1 km), while the road route adds roughly 24.2 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 8:00 AM to 10:00 AM CDT. If you want a more comfortable same-day return, try to leave by 2:46 PM CDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $15.23 one way or $30.47 round trip. Estimated CO2 is about 35.9 kg one way.
What should you check before leaving?
Before you leave, expect Sunny around Marion and Sunny near O'Fallon.
Stop Ideas Near Montgomery City
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 Montgomery City.
Hermann
Washington
Jefferson City
Kirkwood
Flight Path Map
This map shows the direct air route between Marion and O'Fallon. Straight-line distance: 90.17 mi (145.12 km).
#1 Marion
Human settlement in United States of America
| Population | 2,164 |
| Coordinates | 38.6908700, -92.3663000 |
| Altitude | 177 |
| 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: 184 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 03h 48m |
| 40 mph (64.37 km/h) | 02h 51m |
| 50 mph (80.47 km/h) | 02h 17m |
| 60 mph (96.56 km/h) | 01h 54m |
| 70 mph (112.65 km/h) | 01h 38m |
| 80 mph (129 km/h) | 01h 25m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.77 | $15.23 | $30.47 |
| Mid-grade | $4.25 | $17.18 | $34.36 |
| Premium | $4.65 | $18.80 | $37.60 |
| Diesel | $5.30 | $21.43 | $42.86 |
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 · May 02, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.