How far is St. Louis, MO from Union, MO?

The driving distance from St. Louis, MO to Union, MO is about 50.3 miles (81 km), with a travel time of about 01h 05m by car.

  • The straight-line flight distance is about 45.5 miles (73.2 km).
  • For a round trip, plan for roughly 02h 10m of driving time before adding stops, traffic, or weather delays.
  • A comfortable departure window is usually 8:00 AM to 10:00 AM CDT.
Trip Tools

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.

Reverse Route
Quick Snapshot
Road
50.35 mi
01h 05m
Flight
45.48 mi
73.2 km direct

This route works well as a day trip with time at the destination.

Learn Distance

Choose another destination from St. Louis.

Flight Distance

Direct air line
45.48 mi
Kilometers
73.2 km
Flight Time
00h 05m

Driving Distance

Road route
50.35 mi
Kilometers
81.03 km
Drive Time
01h 05m

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 05m.

Arrival Snapshot
Arrive in Union
Sat, May 2, 1:59 AM CDT
Return by in St. Louis
Sat, May 2, 3:04 AM CDT
Useful when you're deciding between a quick errand, a day trip, or a longer stop.
Leave St. Louis
2026-05-02T00:54
Arrive Union
Sat, May 2, 1:59 AM CDT
Route Timing
01h 05m
One way by road
Best Departure Window
8:00 AM to 10:00 AM CDT
Aim for a morning departure
Arrive between
9:05 AM to 11:05 AM CDT

A morning start gives you useful time at the destination and keeps the return out of the late evening.

Leave by
4:20 PM CDT
Keeps a same-day return open with about 03h 00m at the destination.
Back in St. Louis
9:30 PM CDT
Morning start is best

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.

Mid-route stop
Sherman
MO

Unincorporated community in St.

From St. Louis
25.2 mi
00h 32m
To Union
25.2 mi
00h 32m

Route Weather Snapshot

Check the forecast at both ends before you head out.

Origin
63°F
Saturday

Mostly Sunny

Starts
Sat, May 2 6:00 AM CDT
Wind
2 to 9 mph NW
Destination
63°F
Saturday

Mostly Sunny

Starts
Sat, May 2 6:00 AM CDT
Wind
0 to 5 mph NW

Driving Route Map

The map below follows the saved road route between St. Louis and Union.

Turn-by-Turn Driving Directions

Step-by-step road directions between St. Louis and Union.

  1. 1

    Start on Market Street

    1.6 km · 2 min · Market Street

  2. 2

    Turn left onto South Jefferson Avenue

    1.2 mi · 3 min · South Jefferson Avenue

  3. 3

    Take the ramp straight toward I 44 West

    1051 ft · 17 sec

  4. 4

    Merge slight left onto Officer David Haynes Memorial Highway

    2.3 mi · 3 min · Officer David Haynes Memorial Highway

  5. 5

    Continue on Officer Michael Barwick Memorial Highway

    3.5 mi · 4 min · Officer Michael Barwick Memorial Highway

  6. 6

    Continue on Police Officer Robert Stanze Memorial Highway

    2.7 mi · 3 min · Police Officer Robert Stanze Memorial Highway

  7. 7

    Continue on Police Officer Ernest M. Brockman Sr. Memorial Highway

    3.5 mi · 4 min · Police Officer Ernest M. Brockman Sr. Memorial Highway

  8. 8

    Continue on Henry Shaw Ozark Corridor

    29.9 mi · 34 min · Henry Shaw Ozark Corridor

  9. 9

    Take the exit slight right toward US 50 West: Union, Jefferson City

    1271 ft · 27 sec

  10. 10

    Merge slight left

    4.8 mi · 7 min

  11. 11

    Turn right

    157 m · 15 sec

  12. 12

    Turn left onto East Main Street

    1641 ft · 50 sec · East Main Street

  13. 13

    Turn right onto North McKinley Avenue

    75 m · 7 sec · North McKinley Avenue

  14. 14

    Continue on North McKinley Avenue

    119 m · 15 sec · North McKinley Avenue

  15. 15

    Continue on East State Street

    159 m · 27 sec · East State Street

  16. 16

    Turn right onto North Church Street

    984 ft · 39 sec · North Church Street

  17. 17

    Turn left onto East Park Avenue

    900 ft · 31 sec · East Park Avenue

  18. 18

    Turn left

    19 m · 5 sec

  19. 19

    Arrive at your destination

    0 m · 1 sec

Car Route Details

A richer read on the saved driving route between St. Louis and Union.

OSRM road route
Drive Character

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.

Directions
19 steps
7 turns on the saved route
Ramps & Exits
4
2 merges, 2 ramps or exits
Navigation Density
37.7 / 100 mi
Decision points by distance
Main Roads
Henry Shaw Ozark Corridor
29.9 mi · 59%
US 50 West
5.07 mi · 10%
Police Officer Ernest M. Brockman Sr. Memorial H
3.53 mi · 7%
Officer Michael Barwick Memorial Highway
3.46 mi · 7%
Police Officer Robert Stanze Memorial Highway
2.75 mi · 5%
Officer David Haynes Memorial Highway
2.28 mi · 5%
Longest Stretch

Henry Shaw Ozark Corridor

Continue on Henry Shaw Ozark Corridor

29.9 mi · 00h 34m

Route Summary

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

Trip Read

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.

Drive Time
01h 05m
Day trip friendly
Same-Day Return
02h 10m
Round-trip wheel time
Road vs Air
+4.8 mi
45.5 mi direct line
Halfway Stop
Sherman
00h 32m from St. Louis
Leave By
4:20 PM CDT
Morning start is best
Weather Watch

Mostly Sunny leaving St. Louis and Mostly Sunny near Union.

Trip Questions

Direct answers travelers usually want before committing to the drive.

How long does it take to drive from St. Louis to Union?

The road trip is about 50.3 miles (81 km) and usually takes 01h 05m 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?

Sherman is a useful midpoint, sitting about 25.2 miles from St. Louis and 25.2 miles from Union.

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

The direct path is about 45.5 miles (73.2 km), while the road route adds roughly 4.8 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 8:00 AM to 10:00 AM CDT. If you want a more comfortable same-day return, try to leave by 4:20 PM CDT.

How much will gas cost for this route?

Using about 28.3 MPG, regular gas is estimated at $6.71 one way or $13.42 round trip. Estimated CO2 is about 15.8 kg one way.

What should you check before leaving?

Before you leave, expect Mostly Sunny around St. Louis and Mostly Sunny near Union.

Stop Ideas Near Sherman

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

Mid-route Guidance
Local place coverage is thin around Sherman, 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 Sherman.

RAIL

Kirkwood

17 mi away
110 West Argonne Dr.
RAIL

Gateway Transportation Center

35 mi away
551 South 16th St.
RAIL

Washington

37 mi away
301 West Front St.
RAIL

Alton

57 mi away
3400 College Ave.

Flight Path Map

This map shows the direct air route between St. Louis and Union. Straight-line distance: 45.48 mi (73.2 km).

St. Louis

#1 St. Louis

The second most populous city in Missouri and the center of the St.

Population315,685
Coordinates38.6272700, -90.1978900
Altitude142
CountryUnited States
Union

#2 Union

City in and county seat of Franklin County, Missouri, United States

Population12,094
Coordinates38.4500500, -91.0084800
Altitude162
CountryUnited States
Start: St. Louis (-90.19789, 38.62727)
End: Union (-91.00848, 38.45005)

Estimated Travel Time

Distance: 81 km by road

SpeedTime
30 mph (48.3 km/h)01h 40m
40 mph (64.37 km/h)01h 15m
50 mph (80.47 km/h)01h 00m
60 mph (96.56 km/h)00h 50m
70 mph (112.65 km/h)00h 43m
80 mph (129 km/h)00h 37m

Fuel, Round Trip and CO2

Estimated fuel cost and emissions for this route.

One-way fuel
1.78 gal
6.73 L · about $6.71
Round trip
$13.42
3.56 gal · 13.46 L
Estimated CO2
15.8 kg one way
Round trip: 31.6 kg / 70 lb CO2, using regular gasoline.
Fuel$/galOne wayRound trip
Regular gas $3.77 $6.71 $13.42
Mid-grade $4.25 $7.57 $15.14
Premium $4.65 $8.28 $16.57
Diesel $5.30 $9.44 $18.88

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 · May 02, 2026

There is no time difference between St. Louis and Union. The current time is 00:54:02.

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.