How far is O'Fallon, MO from Imperial, MO?
The driving distance from O'Fallon, MO to Imperial, MO is about 45.7 miles (73.5 km), with a travel time of about 00h 58m by car.
- The straight-line flight distance is about 35 miles (56.4 km).
- For a round trip, plan for roughly 01h 56m 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 00h 58m.
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.
Village in west St.
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 Imperial.
Turn-by-Turn Driving Directions
Step-by-step road directions between O'Fallon and Imperial.
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1
Start on the route
8 m · 7 sec
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2
Turn left onto South Main Street
3116 ft · 2 min · South Main Street
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3
Turn left onto Drennen Parkway
1.4 km · 1 min · Drennen Parkway
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4
Take the ramp slight left toward I 70 East: Saint Louis
133 m · 6 sec
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5
Merge slight left
13.5 mi · 17 min
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6
Take the exit slight right toward I 270: Chicago, Memphis
872 ft · 12 sec
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7
Keep slight right to continue on I 270 South: Memphis
2339 ft · 33 sec
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8
Continue on I 270 South: Memphis
723 ft · 10 sec
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9
Merge slight left
19 mi · 24 min
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10
Take the exit slight right toward I 55, US 61, US 67: Saint Louis, Memphis, Lemay Ferry Road
1911 ft · 27 sec
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11
Keep slight right to continue on I 55 South: Memphis
2031 ft · 44 sec
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12
Merge slight left onto Rosa Parks Highway
1.5 mi · 2 min · Rosa Parks Highway
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13
Continue on Officer Thomas G. Smith, Jr. Memorial Highway
1.8 mi · 2 min · Officer Thomas G. Smith, Jr. Memorial Highway
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14
Continue on Police Officer Steven Jarvis Memorial Highway
6.1 mi · 7 min · Police Officer Steven Jarvis Memorial Highway
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15
Take the exit slight right toward Imperial Main Street
1439 ft · 31 sec
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16
Turn left onto Imperial Main Street, Imperial, Kimmswick
31 m · 6 sec
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17
Turn left onto Imperial Main Street
1121 ft · 30 sec · Imperial Main Street
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18
Turn left onto Old State Road
85 m · 15 sec · Old State Road
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19
Turn right onto White Street
126 m · 18 sec · White Street
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20
Arrive at your destination
0 m · 1 sec · White Street
Car Route Details
A richer read on the saved driving route between O'Fallon and Imperial.
Highway-focused drive
Most of the mileage stays on named highways, so the important moments are ramps, exits, merges, and the final local approach.
I 270 South
Merge slight left
19 mi · 00h 24m
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 O'Fallon and Sunny near Imperial.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from O'Fallon to Imperial?
The road trip is about 45.7 miles (73.5 km) and usually takes 00h 58m 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?
Westwood is a useful midpoint, sitting about 22.9 miles from O'Fallon and 22.9 miles from Imperial.
How much longer is the road route than the straight-line distance?
The direct path is about 35 miles (56.4 km), while the road route adds roughly 10.7 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 8:00 AM to 10:00 AM CDT. If you want a more comfortable same-day return, try to leave by 4:34 PM CDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $6.07 one way or $12.14 round trip. Estimated CO2 is about 14.3 kg one way.
What should you check before leaving?
Before you leave, expect Sunny around O'Fallon and Sunny near Imperial.
Stop Ideas Near Westwood
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 Westwood.
Kirkwood
Gateway Transportation Center
Alton
Washington
Flight Path Map
This map shows the direct air route between O'Fallon and Imperial. Straight-line distance: 35.06 mi (56.42 km).
#1 O'Fallon
The most populous city in St.
| Population | 89,769 |
| Coordinates | 38.8106100, -90.6998500 |
| Altitude | 165 |
| Country | United States |
#2 Imperial
Imperial is a place in Missouri, United States.
| Population | 0 |
| Coordinates | 38.3697800, -90.3784500 |
| Altitude | 135 |
| Country | United States |
End: Imperial (-90.37845, 38.36978)
Estimated Travel Time
Distance: 74 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 01h 31m |
| 40 mph (64.37 km/h) | 01h 08m |
| 50 mph (80.47 km/h) | 00h 54m |
| 60 mph (96.56 km/h) | 00h 45m |
| 70 mph (112.65 km/h) | 00h 39m |
| 80 mph (129 km/h) | 00h 34m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.77 | $6.07 | $12.14 |
| Mid-grade | $4.25 | $6.85 | $13.69 |
| Premium | $4.65 | $7.49 | $14.99 |
| Diesel | $5.30 | $8.54 | $17.08 |
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 13, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.