How far is Eureka, MO from O'Fallon, MO?
The driving distance from Eureka, MO to O'Fallon, MO is about 112.6 miles (181.2 km), with a travel time of about 01h 50m by car.
- The straight-line flight distance is about 94 miles (151.3 km).
- For a round trip, plan for roughly 03h 40m 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 50m.
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.
Route Weather Snapshot
Check the forecast at both ends before you head out.
Mostly Sunny then Chance Showers And Thunderstorms
Mostly Sunny then Chance Showers And Thunderstorms
Driving Route Map
The map below follows the saved road route between Eureka and O'Fallon.
Turn-by-Turn Driving Directions
Step-by-step road directions between Eureka and O'Fallon.
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1
Start on the route
2.5 mi · 6 min
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2
Turn right
7.1 mi · 11 min
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3
Enter the roundabout and take exit 2 toward North Kingshighway Street
39 m · 2 sec · North Kingshighway Street
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4
Exit the roundabout onto North Kingshighway Street
2.4 mi · 4 min · North Kingshighway Street
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5
Continue on North King's Highway
2.8 mi · 4 min · North King's Highway
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6
Turn left
2816 ft · 1 min
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7
Take the ramp right toward I 55 North: Saint Louis
1135 ft · 28 sec
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8
Merge slight left
59.4 mi · 1 hr 4 min
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9
Continue on Rosa Parks Highway
1.3 mi · 2 min · Rosa Parks Highway
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10
Take the exit slight right toward I 270 West, I 255 East: Kansas City, Chicago
1279 ft · 27 sec
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11
Keep slight left to continue on I 270 West: Kansas City
118 m · 8 sec
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12
Continue on I 270 West
1.2 km · 1 min
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13
Merge slight left
18.1 mi · 23 min
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14
Take the exit slight right toward I 70: Kansas City, Saint Louis, Saint Louis Lambert International Airport
1 mi · 1 min
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15
Keep slight left to continue on I 70 West: Kansas City
645 ft · 11 sec
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16
Continue on I 70 West: Kansas City
1 km · 57 sec
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17
Merge slight left
13.6 mi · 17 min
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18
Take the exit slight right toward MO K: O'Fallon, Main Street
119 m · 8 sec
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19
Turn straight onto East Terra Lane
1.4 km · 2 min · East Terra Lane
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20
Turn right onto South Main Street
2830 ft · 1 min · South Main Street
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21
Turn right
8 m · 2 sec
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22
Arrive at your destination
0 m · 1 sec
Car Route Details
A richer read on the saved driving route between Eureka 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.
I 55 North
Merge slight left
59.4 mi · 01h 04m
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.
Mostly Sunny then Chance Showers And Thunderstorms leaving Eureka and Mostly Sunny then Chance 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 Eureka to O'Fallon?
The road trip is about 112.6 miles (181.2 km) and usually takes 01h 50m 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?
Festus is a useful midpoint, sitting about 56.2 miles from Eureka and 56.4 miles from O'Fallon.
How much longer is the road route than the straight-line distance?
The direct path is about 94 miles (151.3 km), while the road route adds roughly 18.6 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 2:50 PM CDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $14.97 one way or $29.94 round trip. Estimated CO2 is about 35.3 kg one way.
What should you check before leaving?
Before you leave, expect Mostly Sunny then Chance Showers And Thunderstorms around Eureka and Mostly Sunny then Chance Showers And Thunderstorms near O'Fallon.
Stop Ideas Near Festus
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 Festus.
Kirkwood
Gateway Transportation Center
Washington
Alton
Flight Path Map
This map shows the direct air route between Eureka and O'Fallon. Straight-line distance: 94.04 mi (151.34 km).
#1 Eureka
City located in St.
| Population | 11,323 |
| Coordinates | 37.6789400, -89.7370500 |
| Altitude | 195 |
| 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: 181 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 03h 45m |
| 40 mph (64.37 km/h) | 02h 48m |
| 50 mph (80.47 km/h) | 02h 15m |
| 60 mph (96.56 km/h) | 01h 52m |
| 70 mph (112.65 km/h) | 01h 36m |
| 80 mph (129 km/h) | 01h 24m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.77 | $14.97 | $29.94 |
| Mid-grade | $4.25 | $16.88 | $33.77 |
| Premium | $4.65 | $18.48 | $36.95 |
| Diesel | $5.30 | $21.06 | $42.11 |
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 17, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.