How far is O'Fallon, MO from Brentwood, MO?
The driving distance from O'Fallon, MO to Brentwood, MO is about 29.3 miles (47.2 km), with a travel time of about 00h 40m by car.
- The straight-line flight distance is about 23.1 miles (37.2 km).
- For a round trip, plan for roughly 01h 20m 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 40m.
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 Likely
Driving Route Map
The map below follows the saved road route between O'Fallon and Brentwood.
Turn-by-Turn Driving Directions
Step-by-step road directions between O'Fallon and Brentwood.
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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
6.9 mi · 9 min
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10
Take the exit slight right toward I 64, US 40, US 61: Saint Louis, Wentzville
840 ft · 18 sec
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11
Keep slight left to continue on I 64 East, US 40 East, US 61 South: Saint Louis
1938 ft · 41 sec
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12
Continue on I 64 East, US 40 East, US 61 South: Saint Louis
1108 ft · 21 sec
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13
Keep slight left to continue on I 64, US 40, US 61: Saint Louis
920 ft · 13 sec
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14
Continue on I 64 East, US 40 East, US 61 South: Saint Louis
681 ft · 10 sec
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15
Merge slight left onto Avenue of the Saints
1.4 mi · 2 min · Avenue of the Saints
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16
Continue on Daniel Boone Expressway
2.6 mi · 3 min · Daniel Boone Expressway
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17
Take the exit slight right toward McKnight Road
960 ft · 24 sec
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18
Turn right onto South McKnight Road
1.2 km · 1 min · South McKnight Road
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19
Turn left onto Litzsinger Road
1.1 km · 2 min · Litzsinger Road
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20
Turn right
18 m · 10 sec
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21
Turn left
21 m · 5 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 O'Fallon and Brentwood.
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 East
Merge slight left
13.5 mi · 00h 17m
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 O'Fallon and Showers And Thunderstorms Likely near Brentwood.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from O'Fallon to Brentwood?
The road trip is about 29.3 miles (47.2 km) and usually takes 00h 40m 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?
Bridgeton is a useful midpoint, sitting about 14.7 miles from O'Fallon and 14.7 miles from Brentwood.
How much longer is the road route than the straight-line distance?
The direct path is about 23.1 miles (37.2 km), while the road route adds roughly 6.2 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 7:10 PM CDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $3.92 one way or $7.84 round trip. Estimated CO2 is about 9.2 kg one way.
What should you check before leaving?
Before you leave, expect Showers And Thunderstorms around O'Fallon and Showers And Thunderstorms Likely near Brentwood.
Stop Ideas Near Bridgeton
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 Bridgeton.
Kirkwood
Gateway Transportation Center
Alton
Washington
Flight Path Map
This map shows the direct air route between O'Fallon and Brentwood. Straight-line distance: 23.13 mi (37.23 km).
#1 O'Fallon
The most populous city in St.
| Population | 89,769 |
| Coordinates | 38.8106100, -90.6998500 |
| Altitude | 165 |
| Country | United States |
#2 Brentwood
Inner-ring suburb of St.
| Population | 7,953 |
| Coordinates | 38.6175500, -90.3492800 |
| Altitude | 146 |
| Country | United States |
End: Brentwood (-90.34928, 38.61755)
Estimated Travel Time
Distance: 47 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 00h 58m |
| 40 mph (64.37 km/h) | 00h 44m |
| 50 mph (80.47 km/h) | 00h 35m |
| 60 mph (96.56 km/h) | 00h 29m |
| 70 mph (112.65 km/h) | 00h 25m |
| 80 mph (129 km/h) | 00h 21m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.77 | $3.92 | $7.84 |
| Mid-grade | $4.25 | $4.42 | $8.85 |
| Premium | $4.65 | $4.84 | $9.68 |
| Diesel | $5.30 | $5.52 | $11.03 |
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 18, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.