How far is Round Rock, TX from San Antonio, TX?

The driving distance from Round Rock, TX to San Antonio, TX is about 120 miles (193.1 km), with a travel time of about 01h 45m by car.

  • The straight-line flight distance is about 89.4 miles (143.8 km).
  • For a round trip, plan for roughly 03h 31m 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
119.99 mi
01h 45m
Flight
89.38 mi
143.85 km direct

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

Learn Distance

Choose another destination from Round Rock.

Flight Distance

Direct air line
89.38 mi
Kilometers
143.85 km
Flight Time
00h 10m

Driving Distance

Road route
119.99 mi
Kilometers
193.11 km
Drive Time
01h 45m

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 45m.

Arrival Snapshot
Arrive in San Antonio
Wed, Apr 22, 8:18 PM CDT
Return by in Round Rock
Wed, Apr 22, 10:04 PM CDT
Useful when you're deciding between a quick errand, a day trip, or a longer stop.
Leave Round Rock
2026-04-22T18:33
Arrive San Antonio
Wed, Apr 22, 8:18 PM CDT
Route Timing
01h 45m
One way by road
Best Departure Window
8:00 AM to 10:00 AM CDT
Aim for a morning departure
Arrive between
9:46 AM to 11:46 AM CDT

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

Leave by
2:58 PM CDT
Keeps a same-day return open with about 03h 00m at the destination.
Back in Round Rock
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
San Marcos
TX

The most populous city in Hays County, Texas.

From Round Rock
48.7 mi
00h 52m
To San Antonio
71.3 mi
00h 52m

Route Weather Snapshot

Check the forecast at both ends before you head out.

Origin
80°F
Wednesday

Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms

Starts
Wed, Apr 22 6:00 AM CDT
Wind
5 to 10 mph SE
Destination
82°F
Wednesday

Chance Showers And Thunderstorms then Slight Chance Showers And Thunderstorms

Starts
Wed, Apr 22 6:00 AM CDT
Wind
5 mph SE

Driving Route Map

The map below follows the saved road route between Round Rock and San Antonio.

Turn-by-Turn Driving Directions

Step-by-step road directions between Round Rock and San Antonio.

  1. 1

    Start on South Mays Street

    142 m · 19 sec · South Mays Street

  2. 2

    Turn left onto West Liberty Avenue

    573 ft · 17 sec · West Liberty Avenue

  3. 3

    At the end of the road, turn right onto Round Rock Avenue

    1915 ft · 52 sec · Round Rock Avenue

  4. 4

    Turn sharp left onto North Interstate 35

    1228 ft · 20 sec · North Interstate 35

  5. 5

    Turn straight onto I 35 South

    956 ft · 23 sec

  6. 6

    Merge slight left onto Purple Heart Trail

    14.8 mi · 16 min · Purple Heart Trail

  7. 7

    Keep slight left to continue on Purple Heart Trail

    49.8 mi · 55 min · Purple Heart Trail

  8. 8

    Continue on Interstate Highway 35

    1.7 mi · 2 min · Interstate Highway 35

  9. 9

    Continue on Purple Heart Trail

    11.9 mi · 13 min · Purple Heart Trail

  10. 10

    Continue on North Pan Am Expressway

    10 mi · 12 min · North Pan Am Expressway

  11. 11

    Keep slight left to continue on North Pan Am Expressway

    6.4 mi · 8 min · North Pan Am Expressway

  12. 12

    Keep slight left to continue on North Pan Am Expressway

    2907 ft · 41 sec · North Pan Am Expressway

  13. 13

    Take the exit slight right toward Lexington Avenue, Main Avenue, San Pedro Avenue

    684 ft · 17 sec

  14. 14

    Turn straight onto East Elmira Street

    526 ft · 17 sec · East Elmira Street

  15. 15

    Turn left onto North Main Avenue

    830 ft · 19 sec · North Main Avenue

  16. 16

    Enter the roundabout and take exit 2 toward Navarro Street

    49 m · 3 sec · Navarro Street

  17. 17

    Exit the roundabout onto Navarro Street

    34 m · 2 sec · Navarro Street

  18. 18

    Keep slight right to continue on North Main Avenue

    2181 ft · 52 sec · North Main Avenue

  19. 19

    Turn right onto West Travis Street

    68 m · 11 sec · West Travis Street

  20. 20

    Turn left onto North Flores Street

    807 ft · 20 sec · North Flores Street

  21. 21

    Continue on Military Plaza

    119 m · 16 sec · Military Plaza

  22. 22

    Turn left onto Dolorosa Street

    100 m · 8 sec · Dolorosa Street

  23. 23

    Arrive at your destination

    0 m · 1 sec · Dolorosa Street

Car Route Details

A richer read on the saved driving route between Round Rock and San Antonio.

OSRM road route
Drive Character

Straightforward drive

The saved road route has a manageable number of maneuvers and should be easy to follow with normal attention to signs.

Directions
23 steps
11 turns on the saved route
Ramps & Exits
4
1 merges, 3 ramps or exits
Navigation Density
19.2 / 100 mi
Decision points by distance
Main Roads
Purple Heart Trail
76.5 mi · 64%
North Pan Am Expressway
17 mi · 14%
Interstate Highway 35
1.73 mi · 1%
North Main Avenue
0.57 mi
Round Rock Avenue
0.36 mi
North Interstate 35
0.23 mi
Longest Stretch

Purple Heart Trail

Keep slight left to continue on Purple Heart Trail

49.8 mi · 00h 55m

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 45m
Day trip friendly
Same-Day Return
03h 32m
Round-trip wheel time
Road vs Air
+30.6 mi
89.4 mi direct line
Halfway Stop
San Marcos
00h 52m from Round Rock
Leave By
2:58 PM CDT
Morning start is best
Weather Watch

Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms leaving Round Rock and Chance Showers And Thunderstorms then Slight Chance Showers And Thunderstorms near San Antonio.

Trip Questions

Direct answers travelers usually want before committing to the drive.

How long does it take to drive from Round Rock to San Antonio?

The road trip is about 120 miles (193.1 km) and usually takes 01h 45m 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?

San Marcos is a useful midpoint, sitting about 48.7 miles from Round Rock and 71.3 miles from San Antonio.

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

The direct path is about 89.4 miles (143.8 km), while the road route adds roughly 30.6 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 2:58 PM CDT.

How much will gas cost for this route?

Using about 28.3 MPG, regular gas is estimated at $15.99 one way or $31.97 round trip. Estimated CO2 is about 37.6 kg one way.

What should you check before leaving?

Before you leave, expect Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms around Round Rock and Chance Showers And Thunderstorms then Slight Chance Showers And Thunderstorms near San Antonio.

Stop Ideas Near San Marcos

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

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

RAIL

San Marcos Station

1 mi away
338 South Guadalupe St.
RAIL

Austin

46 mi away
250 North Lamar Blvd.
RAIL

San Antonio Station

73 mi away
350 Hoefgen Street
RAIL

Taylor

92 mi away
118 East First St.

Flight Path Map

This map shows the direct air route between Round Rock and San Antonio. Straight-line distance: 89.38 mi (143.85 km).

Round Rock

#1 Round Rock

The fourth most populous city in Williamson County, Texas.

Population137,575
Coordinates30.5082600, -97.6789000
Altitude224
CountryUnited States
San Antonio

#2 San Antonio

The seventh most populous city in the United States and the center of the San Antonio metropolitan area.

Population1,567,118
Coordinates29.4241200, -98.4936300
Altitude198
CountryUnited States
Start: South Mays Street (-97.678712, 30.508316)
End: Dolorosa Street (-98.493645, 29.424163)

Estimated Travel Time

Distance: 193 km by road

SpeedTime
30 mph (48.3 km/h)03h 59m
40 mph (64.37 km/h)03h 00m
50 mph (80.47 km/h)02h 23m
60 mph (96.56 km/h)01h 59m
70 mph (112.65 km/h)01h 42m
80 mph (129 km/h)01h 29m

Fuel, Round Trip and CO2

Estimated fuel cost and emissions for this route.

One-way fuel
4.23 gal
16.03 L · about $15.99
Round trip
$31.97
8.46 gal · 32.06 L
Estimated CO2
37.6 kg one way
Round trip: 75.2 kg / 166 lb CO2, using regular gasoline.
Fuel$/galOne wayRound trip
Regular gas $3.78 $15.99 $31.97
Mid-grade $4.25 $17.99 $35.97
Premium $4.59 $19.42 $38.84
Diesel $3.99 $16.89 $33.78

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 Texas · Apr 22, 2026

There is no time difference between Round Rock and San Antonio. The current time is 18:33:12.

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.