How far is O'Fallon, MO from Lake Saint Louis, MO?
The driving distance from O'Fallon, MO to Lake Saint Louis, MO is about 6.5 miles (10.5 km), with a travel time of about 00h 11m by car.
- The straight-line flight distance is about 4.7 miles (7.6 km).
- For a round trip, plan for roughly 00h 23m 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 11m.
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.
City in Saint Charles 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 Lake Saint Louis.
Turn-by-Turn Driving Directions
Step-by-step road directions between O'Fallon and Lake Saint Louis.
-
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 I 70 East
10 m · 6 sec
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4
Turn sharp left onto South Main Street
87 m · 11 sec · South Main Street
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5
Turn left onto West Terra Lane
576 ft · 12 sec · West Terra Lane
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6
Take the ramp straight toward I 70 West
146 m · 7 sec
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7
Merge slight left
3.5 mi · 4 min
-
8
Take the exit slight right toward Lake Saint Louis Boulevard
878 ft · 27 sec
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9
Turn left onto Lake Saint Louis Boulevard
132 m · 12 sec · Lake Saint Louis Boulevard
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10
Enter the roundabout and take exit 1 toward Veterans Memorial Parkway
26 m · 2 sec · Veterans Memorial Parkway
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11
Exit the roundabout onto Veterans Memorial Parkway
1.2 mi · 2 min · Veterans Memorial Parkway
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12
Turn left onto De Loire Drive
1517 ft · 1 min · De Loire Drive
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13
At the end of the road, turn left onto Savoy Drive
2289 ft · 1 min · Savoy Drive
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14
Arrive at your destination
0 m · 1 sec · Savoy Drive
Car Route Details
A richer read on the saved driving route between O'Fallon and Lake Saint Louis.
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.
I 70 West
Merge slight left
3.46 mi · 00h 04m
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.
Sunny leaving O'Fallon and Sunny near Lake Saint Louis.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from O'Fallon to Lake Saint Louis?
The road trip is about 6.5 miles (10.5 km) and usually takes 00h 11m 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?
Dardenne Prairie is a useful midpoint, sitting about 3.2 miles from O'Fallon and 3.2 miles from Lake Saint Louis.
How much longer is the road route than the straight-line distance?
The direct path is about 4.7 miles (7.6 km), while the road route adds roughly 1.8 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 7:00 AM to 7:00 PM CDT. If you want a more comfortable same-day return, try to leave by 8:06 PM CDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $0.87 one way or $1.73 round trip. Estimated CO2 is about 2 kg one way.
What should you check before leaving?
Before you leave, expect Sunny around O'Fallon and Sunny near Lake Saint Louis.
Stop Ideas Near Dardenne Prairie
Useful break, food, and waypoint ideas within about 15 miles of the route midpoint.
City Hall Park
City of O'Fallon
Swingley Ridge @ Chesterfield City Hall SB
Transit and Meeting Points
Useful pickup, handoff, or rendezvous points close to Dardenne Prairie.
Washington
Kirkwood
Gateway Transportation Center
Alton
Flight Path Map
This map shows the direct air route between O'Fallon and Lake Saint Louis. Straight-line distance: 4.71 mi (7.58 km).
#1 O'Fallon
The most populous city in St.
| Population | 89,769 |
| Coordinates | 38.8106100, -90.6998500 |
| Altitude | 165 |
| Country | United States |
#2 Lake Saint Louis
City in Saint Charles County, Missouri, United States
| Population | 17,186 |
| Coordinates | 38.7975500, -90.7856800 |
| Altitude | 172 |
| Country | United States |
End: Lake Saint Louis (-90.78568, 38.79755)
Estimated Travel Time
Distance: 10 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 00h 13m |
| 40 mph (64.37 km/h) | 00h 09m |
| 50 mph (80.47 km/h) | 00h 07m |
| 60 mph (96.56 km/h) | 00h 06m |
| 70 mph (112.65 km/h) | 00h 05m |
| 80 mph (129 km/h) | 00h 04m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.77 | $0.87 | $1.73 |
| Mid-grade | $4.25 | $0.98 | $1.96 |
| Premium | $4.65 | $1.07 | $2.14 |
| Diesel | $5.30 | $1.22 | $2.44 |
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 20, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.