How far is Troy, MO from O'Fallon, MO?
The driving distance from Troy, MO to O'Fallon, MO is about 24.3 miles (39.1 km), with a travel time of about 00h 26m by car.
- The straight-line flight distance is about 19.1 miles (30.7 km).
- For a round trip, plan for roughly 00h 52m of driving time before adding stops, traffic, or weather delays.
- A comfortable departure window is usually 7:00 AM to 7:00 PM CDT.
Reverse, save, or send this route
This is an easy same-day return drive. Copy the route link, send it to another device, or print a clean version before you head out.
This is an easy same-day return drive.
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 26m.
This is a short drive, so your comfort window is wide. Traffic and current weather matter more than the clock.
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.
Route Weather Snapshot
Check the forecast at both ends before you head out.
Showers And Thunderstorms
Showers And Thunderstorms
Driving Route Map
The map below follows the saved road route between Troy and O'Fallon.
Turn-by-Turn Driving Directions
Step-by-step road directions between Troy and O'Fallon.
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1
Start on the route
30 m · 12 sec
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2
At the end of the road, turn left onto 2nd Street
30 m · 7 sec · 2nd Street
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3
Turn right onto East Cherry Street
1042 ft · 21 sec · East Cherry Street
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4
Enter the roundabout and take exit 1 toward East Cherry Street
35 m · 3 sec · East Cherry Street
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5
Exit the roundabout onto East Cherry Street
2215 ft · 50 sec · East Cherry Street
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6
Turn left onto North Lincoln Drive
1177 ft · 24 sec · North Lincoln Drive
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7
Turn slight right
63 m · 8 sec
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8
Turn slight right
837 ft · 21 sec
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9
Take the ramp slight right toward US 61 South: Saint Louis
1011 ft · 15 sec
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10
Merge slight left onto Avenue of the Saints
15.1 mi · 19 min · Avenue of the Saints
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11
Take the exit slight left toward I 70 East: Saint Louis
2705 ft · 51 sec
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12
Merge slight left onto Dwight D Eisenhower Highway
6.4 mi · 8 min · Dwight D Eisenhower Highway
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13
Take the exit slight right toward MO K: O'Fallon
1765 ft · 43 sec
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14
Turn straight onto Drennen Parkway
46 m · 3 sec · Drennen Parkway
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15
Keep slight right to continue on Drennen Parkway
51 m · 6 sec · Drennen Parkway
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16
Turn slight left onto MO K: O'Fallon
19 m · 3 sec
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17
Continue on South Main Street
3115 ft · 2 min · South Main Street
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18
Turn right
8 m · 2 sec
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19
Arrive at your destination
0 m · 1 sec
Car Route Details
A richer read on the saved driving route between Troy and O'Fallon.
Turn-heavy local drive
The route has frequent decision points for its length, so lane choice and turn timing will matter more than cruising speed.
Avenue of the Saints
Merge slight left onto Avenue of the Saints
15.1 mi · 00h 19m
Route Summary
A quick read on whether this route feels easy, ambitious, or worth planning around.
A short regional drive
This route is short enough to handle as a quick errand, commute, or easy same-day return without much planning overhead.
Showers And Thunderstorms leaving Troy and Showers And Thunderstorms near O'Fallon.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from Troy to O'Fallon?
The road trip is about 24.3 miles (39.1 km) and usually takes 00h 26m in normal driving conditions.
Is this a same-day trip or an overnight route?
This route is short enough to handle as a quick errand, commute, or easy same-day return without much planning overhead.
What is the halfway point on this route?
Wentzville is a useful midpoint, sitting about 12.1 miles from Troy and 12.2 miles from O'Fallon.
How much longer is the road route than the straight-line distance?
The direct path is about 19.1 miles (30.7 km), while the road route adds roughly 5.2 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 7:00 AM to 7:00 PM CDT. If you want a more comfortable same-day return, try to leave by 7:38 PM CDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $3.24 one way or $6.49 round trip. Estimated CO2 is about 7.6 kg one way.
What should you check before leaving?
Before you leave, expect Showers And Thunderstorms around Troy and Showers And Thunderstorms near O'Fallon.
Stop Ideas Near Wentzville
Useful break, food, and waypoint ideas within about 15 miles of the route midpoint.
City Hall Park
City of O'Fallon
Transit and Meeting Points
Useful pickup, handoff, or rendezvous points close to Wentzville.
Washington
Kirkwood
Hermann
Gateway Transportation Center
Flight Path Map
This map shows the direct air route between Troy and O'Fallon. Straight-line distance: 19.08 mi (30.71 km).
#1 Troy
City in Lincoln County, Montana, USA
| Population | 13,341 |
| Coordinates | 38.9794900, -90.9807000 |
| Altitude | 165 |
| 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: 39 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 00h 48m |
| 40 mph (64.37 km/h) | 00h 36m |
| 50 mph (80.47 km/h) | 00h 29m |
| 60 mph (96.56 km/h) | 00h 24m |
| 70 mph (112.65 km/h) | 00h 20m |
| 80 mph (129 km/h) | 00h 18m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.77 | $3.24 | $6.49 |
| Mid-grade | $4.25 | $3.66 | $7.32 |
| Premium | $4.65 | $4.00 | $8.00 |
| Diesel | $5.30 | $4.56 | $9.12 |
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 24, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.