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

The driving distance from Union, MO to St. Louis, MO is about 50.9 miles (81.9 km), with a travel time of about 00h 54m by car.

  • The straight-line flight distance is about 45.5 miles (73.2 km).
  • For a round trip, plan for roughly 01h 49m 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
50.9 mi
00h 54m
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 Union.

Flight Distance

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

Driving Distance

Road route
50.9 mi
Kilometers
81.92 km
Drive Time
00h 54m

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 54m.

Arrival Snapshot
Arrive in St. Louis
Sat, May 2, 12:25 AM CDT
Return by in Union
Sat, May 2, 1:20 AM CDT
Useful when you're deciding between a quick errand, a day trip, or a longer stop.
Leave Union
2026-05-01T23:30
Arrive St. Louis
Sat, May 2, 12:25 AM CDT
Route Timing
00h 54m
One way by road
Best Departure Window
8:00 AM to 10:00 AM CDT
Aim for a morning departure
Arrive between
8:55 AM to 10:55 AM CDT

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

Leave by
4:40 PM CDT
Keeps a same-day return open with about 03h 00m at the destination.
Back in Union
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 Union
25.2 mi
00h 27m
To St. Louis
25.7 mi
00h 27m

Route Weather Snapshot

Check the forecast at both ends before you head out.

Origin
62°F
Friday

Mostly Sunny

Starts
Fri, May 1 6:00 AM CDT
Wind
2 to 6 mph N
Destination
62°F
Friday

Mostly Sunny

Starts
Fri, May 1 6:00 AM CDT
Wind
5 to 8 mph N

Driving Route Map

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

Turn-by-Turn Driving Directions

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

  1. 1

    Start on the route

    19 m · 7 sec

  2. 2

    Turn right onto East Park Avenue

    900 ft · 26 sec · East Park Avenue

  3. 3

    Turn right onto North Church Street

    1601 ft · 1 min · North Church Street

  4. 4

    Turn left onto East Main Street

    2119 ft · 1 min · East Main Street

  5. 5

    Turn right

    157 m · 12 sec

  6. 6

    At the end of the road, turn left

    2.4 mi · 4 min

  7. 7

    Merge slight left

    2.5 mi · 3 min

  8. 8

    Keep slight left to continue on I 44 East, US 50 East: Saint Louis

    33.6 mi · 39 min

  9. 9

    Continue on Police Officer Robert Stanze Memorial Highway

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

  10. 10

    Continue on Officer Michael Barwick Memorial Highway

    3.5 mi · 4 min · Officer Michael Barwick Memorial Highway

  11. 11

    Continue on Officer David Haynes Memorial Highway

    2.3 mi · 3 min · Officer David Haynes Memorial Highway

  12. 12

    Take the exit slight right toward Jefferson Avenue

    924 ft · 22 sec

  13. 13

    Turn left onto South Jefferson Avenue

    1.3 mi · 3 min · South Jefferson Avenue

  14. 14

    Turn right onto Market Street

    1.6 km · 2 min · Market Street

  15. 15

    Arrive at your destination

    0 m · 1 sec · Market Street

Car Route Details

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

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
7 turns on the saved route
Ramps & Exits
2
1 merges, 1 ramps or exits
Navigation Density
29.5 / 100 mi
Decision points by distance
Main Roads
I 44 East
33.6 mi · 66%
Officer Michael Barwick Memorial Highway
3.47 mi · 7%
East Main Street
2.88 mi · 6%
Police Officer Robert Stanze Memorial Highway
2.75 mi · 5%
Officer David Haynes Memorial Highway
2.3 mi · 5%
South Jefferson Avenue
1.29 mi · 3%
Longest Stretch

I 44 East

Keep slight left to continue on I 44 East, US 50 East: Saint Louis

33.6 mi · 00h 39m

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
00h 54m
Day trip friendly
Same-Day Return
01h 50m
Round-trip wheel time
Road vs Air
+5.4 mi
45.5 mi direct line
Halfway Stop
Sherman
00h 27m from Union
Leave By
4:40 PM CDT
Morning start is best
Weather Watch

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

Trip Questions

Direct answers travelers usually want before committing to the drive.

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

The road trip is about 50.9 miles (81.9 km) and usually takes 00h 54m 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 Union and 25.7 miles from St. Louis.

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 5.4 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 4:40 PM CDT.

How much will gas cost for this route?

Using about 28.3 MPG, regular gas is estimated at $6.79 one way or $13.58 round trip. Estimated CO2 is about 16 kg one way.

What should you check before leaving?

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

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 Union and St. Louis. Straight-line distance: 45.48 mi (73.2 km).

Union

#1 Union

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

Population12,094
Coordinates38.4500500, -91.0084800
Altitude162
CountryUnited States
St. Louis

#2 St. Louis

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

Population315,685
Coordinates38.6272700, -90.1978900
Altitude142
CountryUnited States
Start: (-91.008643, 38.450052)
End: Market Street (-90.197859, 38.627348)

Estimated Travel Time

Distance: 82 km by road

SpeedTime
30 mph (48.3 km/h)01h 41m
40 mph (64.37 km/h)01h 16m
50 mph (80.47 km/h)01h 01m
60 mph (96.56 km/h)00h 50m
70 mph (112.65 km/h)00h 43m
80 mph (129 km/h)00h 38m

Fuel, Round Trip and CO2

Estimated fuel cost and emissions for this route.

One-way fuel
1.8 gal
6.8 L · about $6.79
Round trip
$13.58
3.6 gal · 13.6 L
Estimated CO2
16 kg one way
Round trip: 32 kg / 71 lb CO2, using regular gasoline.
Fuel$/galOne wayRound trip
Regular gas $3.77 $6.79 $13.58
Mid-grade $4.25 $7.66 $15.31
Premium $4.65 $8.38 $16.75
Diesel $5.30 $9.55 $19.09

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 Union and St. Louis. The current time is 23:30:56.

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.