How far is San Marcos, TX from Austin, TX?
The driving distance from San Marcos, TX to Austin, TX is about 32.1 miles (51.7 km), with a travel time of about 00h 36m by car.
- The straight-line flight distance is about 29.1 miles (46.8 km).
- For a round trip, plan for roughly 01h 12m 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 36m.
This is a short drive, so your comfort window is wide. Traffic and current weather matter more than the clock.
This departure sits inside the recommended comfort window for the route.
Halfway Point
A useful midpoint for breaks, coffee, or meeting in the middle.
City in Hays County, Texas, United States
Route Weather Snapshot
Check the forecast at both ends before you head out.
Partly Sunny
Partly Sunny
Driving Route Map
The map below follows the saved road route between San Marcos and Austin.
Turn-by-Turn Driving Directions
Step-by-step road directions between San Marcos and Austin.
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1
Start on North Guadalupe Street
23 m · 9 sec · North Guadalupe Street
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2
Turn left onto East Hopkins Street
1.1 mi · 2 min · East Hopkins Street
-
3
Turn slight left
1141 ft · 49 sec
-
4
Turn straight onto North Interstate 35
3027 ft · 1 min · North Interstate 35
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5
Take the ramp slight left toward I 35 North
1503 ft · 37 sec
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6
Merge slight left onto Purple Heart Trail
28.1 mi · 31 min · Purple Heart Trail
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7
Take the exit slight right toward 6th - 12th Streets
665 ft · 24 sec
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8
Turn left onto East 6th Street
2863 ft · 1 min · East 6th Street
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9
Turn left onto Congress Avenue
109 m · 18 sec · Congress Avenue
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10
Turn left onto East 5th Street
8 m · 1 sec · East 5th Street
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11
Arrive at your destination
0 m · 1 sec · East 5th Street
Car Route Details
A richer read on the saved driving route between San Marcos and Austin.
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.
Purple Heart Trail
Merge slight left onto Purple Heart Trail
28.1 mi · 00h 31m
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.
Partly Sunny leaving San Marcos and Partly Sunny near Austin.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from San Marcos to Austin?
The road trip is about 32.1 miles (51.7 km) and usually takes 00h 36m 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?
Buda is a useful midpoint, sitting about 15.5 miles from San Marcos and 16.5 miles from Austin.
How much longer is the road route than the straight-line distance?
The direct path is about 29.1 miles (46.8 km), while the road route adds roughly 3 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 7:18 PM CDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $4.27 one way or $8.54 round trip. Estimated CO2 is about 10 kg one way.
What should you check before leaving?
Before you leave, expect Partly Sunny around San Marcos and Partly Sunny near Austin.
Stop Ideas Near Buda
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 Buda.
Austin
San Marcos Station
Taylor
San Antonio Station
Flight Path Map
This map shows the direct air route between San Marcos and Austin. Straight-line distance: 29.06 mi (46.76 km).
#1 San Marcos
The most populous city in Hays County, Texas.
| Population | 66,350 |
| Coordinates | 29.8832700, -97.9413900 |
| Altitude | 188 |
| Country | United States |
#2 Austin
The eleventh most populous city in the United States and the center of the Austin metropolitan area.
| Population | 995,484 |
| Coordinates | 30.2671500, -97.7430600 |
| Altitude | 149 |
| Country | United States |
End: East 5th Street (-97.743073, 30.267115)
Estimated Travel Time
Distance: 52 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 01h 04m |
| 40 mph (64.37 km/h) | 00h 48m |
| 50 mph (80.47 km/h) | 00h 38m |
| 60 mph (96.56 km/h) | 00h 32m |
| 70 mph (112.65 km/h) | 00h 27m |
| 80 mph (129 km/h) | 00h 24m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.78 | $4.27 | $8.54 |
| Mid-grade | $4.25 | $4.80 | $9.61 |
| Premium | $4.59 | $5.19 | $10.38 |
| Diesel | $3.99 | $4.51 | $9.02 |
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 17, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.