How far is O'Fallon, MO from La Monte, MO?

The driving distance from O'Fallon, MO to La Monte, MO is about 170.8 miles (274.9 km), with a travel time of about 03h 21m by car.

  • The straight-line flight distance is about 146.8 miles (236.2 km).
  • For a round trip, plan for roughly 06h 43m of driving time before adding stops, traffic, or weather delays.
  • A comfortable departure window is usually 6:00 AM to 8:00 AM CDT.
Trip Tools

Reverse, save, or send this route

This drive is better planned with a longer stop or an overnight stay. Copy the route link, send it to another device, or print a clean version before you head out.

Reverse Route
Quick Snapshot
Road
170.83 mi
03h 21m
Flight
146.79 mi
236.23 km direct

This drive is better planned with a longer stop or an overnight stay.

Learn Distance

Choose another destination from O'Fallon.

Flight Distance

Direct air line
146.79 mi
Kilometers
236.23 km
Flight Time
00h 17m

Driving Distance

Road route
170.83 mi
Kilometers
274.93 km
Drive Time
03h 21m

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 03h 21m.

Arrival Snapshot
Arrive in La Monte
Sun, Apr 19, 10:13 AM CDT
Return by in O'Fallon
Sun, Apr 19, 1:34 PM CDT
Useful when you're deciding between a quick errand, a day trip, or a longer stop.
Leave O'Fallon
2026-04-19T06:51
Arrive La Monte
Sun, Apr 19, 10:13 AM CDT
Route Timing
03h 21m
One way by road
Best Departure Window
6:00 AM to 8:00 AM CDT
Leave early for more breathing room
Arrive between
9:22 AM to 11:22 AM CDT

An early departure helps you fit a real stop into the day without turning the return into a late-night drive.

Leave by
10:16 AM CDT
Keeps a same-day return open with about 04h 00m at the destination.
Back in O'Fallon
9:00 PM CDT
Early departure recommended

This departure sits inside the recommended comfort window for the route.

Halfway Point

A useful midpoint for breaks, coffee, or meeting in the middle.

Mid-route stop
Columbia
MO

The most populous city in the state of Missouri.

From O'Fallon
85.3 mi
01h 40m
To La Monte
85.6 mi
01h 40m

Route Weather Snapshot

Check the forecast at both ends before you head out.

Origin
63°F
Sunday

Sunny

Starts
Sun, Apr 19 6:00 AM CDT
Wind
12 mph W
Destination
66°F
Sunday

Sunny

Starts
Sun, Apr 19 6:00 AM CDT
Wind
6 to 12 mph W

Driving Route Map

The map below follows the saved road route between O'Fallon and La Monte.

Turn-by-Turn Driving Directions

Step-by-step road directions between O'Fallon and La Monte.

  1. 1

    Start on the route

    8 m · 7 sec

  2. 2

    Turn left onto South Main Street

    3116 ft · 2 min · South Main Street

  3. 3

    Turn left onto I 70 East

    10 m · 6 sec

  4. 4

    Turn sharp left onto South Main Street

    87 m · 11 sec · South Main Street

  5. 5

    Turn left onto West Terra Lane

    576 ft · 12 sec · West Terra Lane

  6. 6

    Take the ramp straight toward I 70 West

    146 m · 7 sec

  7. 7

    Merge slight left

    139.5 mi · 2 hr 40 min

  8. 8

    Take the exit slight right toward US 65 South: Sedalia

    1094 ft · 37 sec

  9. 9

    Merge slight left

    18.6 mi · 23 min

  10. 10

    Turn right onto West Broadway Boulevard

    10.8 mi · 14 min · West Broadway Boulevard

  11. 11

    Take the exit right

    26 m · 4 sec

  12. 12

    Turn right onto Front Street

    678 ft · 19 sec · Front Street

  13. 13

    Turn left onto South Main Street

    1.2 km · 1 min · South Main Street

  14. 14

    Turn left onto West Pine Street

    67 m · 10 sec · West Pine Street

  15. 15

    Arrive at your destination

    0 m · 1 sec · West Pine Street

Car Route Details

A richer read on the saved driving route between O'Fallon and La Monte.

OSRM road route
Drive Character

Highway-focused drive

Most of the mileage stays on named highways, so the important moments are ramps, exits, merges, and the final local approach.

Directions
15 steps
8 turns on the saved route
Ramps & Exits
5
2 merges, 3 ramps or exits
Navigation Density
8.8 / 100 mi
Decision points by distance
Main Roads
I 70 West
140 mi · 82%
US 65 South
18.8 mi · 11%
West Broadway Boulevard
10.8 mi · 6%
South Main Street
1.39 mi · 1%
Front Street
0.13 mi
West Terra Lane
0.11 mi
Longest Stretch

I 70 West

Merge slight left

139 mi · 02h 40m

Route Summary

A quick read on whether this route feels easy, ambitious, or worth planning around.

Trip Read

A longer out-and-back drive

This is still possible in one day, but it becomes a long driving day. Leaving early and planning your stop window matters more here.

Drive Time
03h 21m
Long day trip
Same-Day Return
06h 44m
Round-trip wheel time
Road vs Air
+24 mi
146.8 mi direct line
Halfway Stop
Columbia
01h 40m from O'Fallon
Leave By
10:16 AM CDT
Early departure recommended
Weather Watch

Sunny leaving O'Fallon and Sunny near La Monte.

Trip Questions

Direct answers travelers usually want before committing to the drive.

How long does it take to drive from O'Fallon to La Monte?

The road trip is about 170.8 miles (274.9 km) and usually takes 03h 21m in normal driving conditions.

Is this a same-day trip or an overnight route?

This is still possible in one day, but it becomes a long driving day. Leaving early and planning your stop window matters more here.

What is the halfway point on this route?

Columbia is a useful midpoint, sitting about 85.3 miles from O'Fallon and 85.6 miles from La Monte.

How much longer is the road route than the straight-line distance?

The direct path is about 146.8 miles (236.2 km), while the road route adds roughly 24 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 6:00 AM to 8:00 AM CDT. If you want a more comfortable same-day return, try to leave by 10:16 AM CDT.

How much will gas cost for this route?

Using about 28.3 MPG, regular gas is estimated at $22.74 one way or $45.48 round trip. Estimated CO2 is about 53.6 kg one way.

What should you check before leaving?

Before you leave, expect Sunny around O'Fallon and Sunny near La Monte.

Stop Ideas Near Columbia

Useful break, food, and waypoint ideas within about 15 miles of the route midpoint.

Mid-route Guidance
Local place coverage is thin around Columbia, so nearby transit and meeting points are shown instead.
Reviewed stop coverage is still thin around this midpoint, so practical transit waypoints are shown on the right.

Transit and Meeting Points

Useful pickup, handoff, or rendezvous points close to Columbia.

RAIL

Jefferson City

44 mi away
101 Jefferson Street
RAIL

Sedalia

82 mi away
100 block of Main Street, through parking lot
RAIL

Hermann

83 mi away
Wharf & Gutenberg Sts.

Flight Path Map

This map shows the direct air route between O'Fallon and La Monte. Straight-line distance: 146.79 mi (236.23 km).

O'Fallon

#1 O'Fallon

The most populous city in St.

Population89,769
Coordinates38.8106100, -90.6998500
Altitude165
CountryUnited States
La Monte

#2 La Monte

City in Pettis County, Missouri, United States

Population1,137
Coordinates38.7741800, -93.4252100
Altitude262
CountryUnited States
Start: O'Fallon (-90.69985, 38.81061)
End: La Monte (-93.42521, 38.77418)

Estimated Travel Time

Distance: 275 km by road

SpeedTime
30 mph (48.3 km/h)05h 41m
40 mph (64.37 km/h)04h 16m
50 mph (80.47 km/h)03h 24m
60 mph (96.56 km/h)02h 50m
70 mph (112.65 km/h)02h 26m
80 mph (129 km/h)02h 07m

Fuel, Round Trip and CO2

Estimated fuel cost and emissions for this route.

One-way fuel
6.03 gal
22.82 L · about $22.74
Round trip
$45.48
12.06 gal · 45.64 L
Estimated CO2
53.6 kg one way
Round trip: 107.2 kg / 236 lb CO2, using regular gasoline.
Fuel$/galOne wayRound trip
Regular gas $3.77 $22.74 $45.48
Mid-grade $4.25 $25.65 $51.29
Premium $4.65 $28.06 $56.13
Diesel $5.30 $31.98 $63.97

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 19, 2026

There is no time difference between O'Fallon and La Monte. The current time is 06:51:28.

Distance to Other Cities

Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.

How did we calculate? Place names are translated into coordinates. The Haversine formula calculates straight-line distance; driving distance uses road network data.