How far is Sullivan, MO from Saint Peters, MO?

The driving distance from Sullivan, MO to Saint Peters, MO is about 78 miles (125.5 km), with a travel time of about 01h 12m by car.

  • The straight-line flight distance is about 50.1 miles (80.6 km).
  • For a round trip, plan for roughly 02h 25m 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
77.97 mi
01h 12m
Flight
50.08 mi
80.59 km direct

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

Learn Distance

Choose another destination from Sullivan.

Flight Distance

Direct air line
50.08 mi
Kilometers
80.59 km
Flight Time
00h 06m

Driving Distance

Road route
77.97 mi
Kilometers
125.48 km
Drive Time
01h 12m

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 12m.

Arrival Snapshot
Arrive in Saint Peters
Thu, Apr 23, 1:29 AM CDT
Return by in Sullivan
Thu, Apr 23, 2:42 AM CDT
Useful when you're deciding between a quick errand, a day trip, or a longer stop.
Leave Sullivan
2026-04-23T00:16
Arrive Saint Peters
Thu, Apr 23, 1:29 AM CDT
Route Timing
01h 12m
One way by road
Best Departure Window
8:00 AM to 10:00 AM CDT
Aim for a morning departure
Arrive between
9:13 AM to 11:13 AM CDT

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

Leave by
4:04 PM CDT
Keeps a same-day return open with about 03h 00m at the destination.
Back in Sullivan
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
Gray Summit
MO

Census designated place

From Sullivan
31.6 mi
00h 36m
To Saint Peters
46.4 mi
00h 36m

Route Weather Snapshot

Check the forecast at both ends before you head out.

Origin
80°F
Thursday

Mostly Sunny

Starts
Thu, Apr 23 6:00 AM CDT
Wind
6 to 15 mph S
Destination
82°F
Thursday

Mostly Sunny

Starts
Thu, Apr 23 6:00 AM CDT
Wind
6 to 16 mph S

Driving Route Map

The map below follows the saved road route between Sullivan and Saint Peters.

Turn-by-Turn Driving Directions

Step-by-step road directions between Sullivan and Saint Peters.

  1. 1

    Start on the route

    17 m · 6 sec

  2. 2

    Turn right onto West Washington Street

    35 m · 3 sec · West Washington Street

  3. 3

    Enter the roundabout and take exit 3 toward West Vine Street

    54 m · 7 sec · West Vine Street

  4. 4

    Exit the roundabout onto West Vine Street

    635 ft · 23 sec · West Vine Street

  5. 5

    Turn left onto South Church Street

    1965 ft · 56 sec · South Church Street

  6. 6

    At the end of the road, turn right onto West Springfield Road

    1.3 km · 1 min · West Springfield Road

  7. 7

    Turn left

    990 ft · 23 sec

  8. 8

    Take the ramp right toward I 44 East: Saint Louis

    842 ft · 21 sec

  9. 9

    Merge slight left

    27.1 mi · 29 min

  10. 10

    Take the exit slight right toward I 44 Business, MO 100 East: Gray Summit

    970 ft · 28 sec

  11. 11

    Turn left onto Manchester Road

    13.4 mi · 19 min · Manchester Road

  12. 12

    Take the exit slight right toward MO 109

    1108 ft · 31 sec

  13. 13

    Enter the roundabout and take exit 3 toward the route

    68 m · 4 sec

  14. 14

    Exit the roundabout

    157 m · 11 sec

  15. 15

    Enter the roundabout and take exit 1 toward the route

    30 m · 2 sec

  16. 16

    Exit the roundabout

    2129 ft · 45 sec

  17. 17

    Enter the roundabout and take exit 2 toward the route

    29 m · 2 sec

  18. 18

    Exit the roundabout

    4.3 mi · 7 min

  19. 19

    Enter the roundabout and take exit 2 toward South Eatherton Road

    29 m · 1 sec · South Eatherton Road

  20. 20

    Exit the roundabout onto South Eatherton Road

    2.4 mi · 5 min · South Eatherton Road

  21. 21

    Continue on Olive Street Road

    1.5 km · 2 min · Olive Street Road

  22. 22

    Take the ramp left toward Chesterfield Airport Road

    1.1 km · 1 min · Chesterfield Airport Road

  23. 23

    Merge slight left onto Avenue of the Saints

    2.7 mi · 3 min · Avenue of the Saints

  24. 24

    Take the exit slight right toward MO 94: Defiance, Saint Charles

    1013 ft · 16 sec

  25. 25

    Keep slight right to continue on MO 94 East: Saint Charles

    95 m · 5 sec

  26. 26

    Merge slight left

    3.4 mi · 5 min

  27. 27

    Keep slight right to continue on Mid Rivers Mall Drive, Pitman Hill Road

    1056 ft · 22 sec

  28. 28

    Turn left onto Mid Rivers Mall Drive

    4.7 mi · 10 min · Mid Rivers Mall Drive

  29. 29

    Take the ramp straight toward I 70 West: Wentzville

    1419 ft · 20 sec

  30. 30

    Merge slight left

    146 m · 7 sec

  31. 31

    Arrive at your destination

    0 m · 1 sec

Car Route Details

A richer read on the saved driving route between Sullivan and Saint Peters.

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
31 steps
16 turns on the saved route
Ramps & Exits
20
4 merges, 16 ramps or exits
Navigation Density
39.7 / 100 mi
Decision points by distance
Main Roads
I 44 East
27.3 mi · 35%
Manchester Road
13.4 mi · 17%
MO 109
5.06 mi · 6%
Mid Rivers Mall Drive
4.93 mi · 6%
MO 94 East
3.5 mi · 4%
Avenue of the Saints
2.71 mi · 3%
Longest Stretch

I 44 East

Merge slight left

27.1 mi · 00h 29m

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 12m
Day trip friendly
Same-Day Return
02h 26m
Round-trip wheel time
Road vs Air
+27.9 mi
50.1 mi direct line
Halfway Stop
Gray Summit
00h 36m from Sullivan
Leave By
4:04 PM CDT
Morning start is best
Weather Watch

Mostly Sunny leaving Sullivan and Mostly Sunny near Saint Peters.

Trip Questions

Direct answers travelers usually want before committing to the drive.

How long does it take to drive from Sullivan to Saint Peters?

The road trip is about 78 miles (125.5 km) and usually takes 01h 12m 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?

Gray Summit is a useful midpoint, sitting about 31.6 miles from Sullivan and 46.4 miles from Saint Peters.

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

The direct path is about 50.1 miles (80.6 km), while the road route adds roughly 27.9 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 4:04 PM CDT.

How much will gas cost for this route?

Using about 28.3 MPG, regular gas is estimated at $10.37 one way or $20.74 round trip. Estimated CO2 is about 24.4 kg one way.

What should you check before leaving?

Before you leave, expect Mostly Sunny around Sullivan and Mostly Sunny near Saint Peters.

Stop Ideas Near Gray Summit

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

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

RAIL

Washington

19 mi away
301 West Front St.
RAIL

Kirkwood

37 mi away
110 West Argonne Dr.
RAIL

Gateway Transportation Center

55 mi away
551 South 16th St.
RAIL

Hermann

59 mi away
Wharf & Gutenberg Sts.

Flight Path Map

This map shows the direct air route between Sullivan and Saint Peters. Straight-line distance: 50.08 mi (80.59 km).

Sullivan

#1 Sullivan

City in Missouri

Population7,117
Coordinates38.2081000, -91.1604200
Altitude299
CountryUnited States
Saint Peters

#2 Saint Peters

The most populous city in St.

Population58,043
Coordinates38.8003300, -90.6265100
Altitude134
CountryUnited States
Start: (-91.160313, 38.208093)
End: I 70 West (-90.626511, 38.800311)

Estimated Travel Time

Distance: 125 km by road

SpeedTime
30 mph (48.3 km/h)02h 35m
40 mph (64.37 km/h)01h 56m
50 mph (80.47 km/h)01h 33m
60 mph (96.56 km/h)01h 17m
70 mph (112.65 km/h)01h 06m
80 mph (129 km/h)00h 58m

Fuel, Round Trip and CO2

Estimated fuel cost and emissions for this route.

One-way fuel
2.75 gal
10.41 L · about $10.37
Round trip
$20.74
5.5 gal · 20.82 L
Estimated CO2
24.4 kg one way
Round trip: 48.9 kg / 108 lb CO2, using regular gasoline.
Fuel$/galOne wayRound trip
Regular gas $3.77 $10.37 $20.74
Mid-grade $4.25 $11.70 $23.39
Premium $4.65 $12.80 $25.60
Diesel $5.30 $14.59 $29.17

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 23, 2026

There is no time difference between Sullivan and Saint Peters. The current time is 00:16:55.

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.