Houston to Austin: Distance and Drive Time

By the Miles Between Cities Editorial Team  ·  Last updated: October 2026

The distance from Houston, Texas to Austin, Texas is 146 miles in a straight line and 164 miles by road, which takes about 3 hr 7 min to drive in free-flowing conditions. Those three numbers answer three different questions, and this page keeps them separate on purpose: the straight-line figure describes the geography between the two city centres, the driving figure describes the road network that connects them, and the time figure translates road miles into the hours a driver should actually budget. Mixing the three up is the most common reason a trip between Houston and Austin gets under-planned, so each figure below carries its own label and its own method.

Houston to Austin at a Glance

Houston sits in the South and Austin in the South. Austin is the more northerly of the two cities and Houston the more southerly, with 0.51 degrees of latitude between them, while Houston stands 2.37 degrees of longitude east of Austin. Those coordinate gaps are what the straight-line calculation turns into miles, and they also shape the trip: a pair separated mostly by longitude is a sunrise-and-sunset trip across time zones, while a pair separated mostly by latitude is a climate trip, where the weather at the far end can feel quite different from the weather at the start even when the road miles are modest.

The Straight-Line Distance: 146 Miles

The straight-line distance between Houston and Austin — sometimes called the as-the-crow-flies or great-circle distance — is 146 miles (235 kilometres). We calculate it with the haversine formula, which measures the shortest path over the curved surface of the Earth between two latitude-and-longitude points. The two points used here are the internal points published for each place in the U.S. Census Bureau Gazetteer files: 29.7857, -95.3888 for Houston and 30.2986, -97.7541 for Austin. Using an official, published coordinate for each city matters, because a distance is only reproducible if both endpoints are fixed and named; anyone can repeat this calculation from the same Gazetteer points and arrive at the same 146 miles. The straight-line figure is the right number for understanding how far apart the cities really are, for comparing this pair with other pairs on an equal footing, and as the starting point for flight-distance thinking. It is not, on its own, a number you can drive.

The Driving Distance: 164 Miles

The driving figure on this page was measured via OpenStreetMap routing using the OSRM engine, which follows the real road network from the Census coordinate of Houston to the Census coordinate of Austin. OSRM summarises the chosen route as: Katy Freeway, TX 71. That road path runs 164 miles (264 kilometres) and the routing engine estimates 3 hr 7 min of driving at the speeds the road data carries. Routing engines choose a fastest path, not necessarily the path a local driver would pick, so a scenic alternative, a toll-free alternative or a route chosen to avoid a particular city centre can add miles to the 164-mile figure.

The gap between the two headline figures — 18 miles, or about 12 percent more road than straight line — is normal, and its size tells you something about the corridor. A small percentage usually means a direct highway happens to run close to the straight line between the cities; a large one usually means terrain, water, a sparse road network or a major detour through an intermediate hub is forcing the road away from the direct line. Neither figure is "wrong": they measure different things, and a careful planner uses the straight line to judge the geography and the road figure to judge the day.

How Long the Drive Takes

Budget about 3 hr 7 min of wheel-turning time for the 164-mile drive from Houston to Austin, and then budget more than that for the trip as actually lived. Routing and estimation both assume a moving vehicle; neither includes fuel stops, meals, rest breaks, roadworks, rush-hour approaches to either city, or weather. On a drive of this length, most drivers add at least one proper stop every two to three hours, and a sensible door-to-door allowance is the driving figure plus roughly ten to twenty percent. If the total crosses eight or nine hours, splitting the journey across two days is usually safer and more pleasant than pressing through tired, and if it crosses a time-zone boundary the arrival clock will not match the departure clock in the way your body expects. Both cities observe Central Time, so the clock does not change on this trip: a departure at nine in the morning and an arrival counted in the same zone need no adjustment, which makes same-day planning between Houston and Austin simpler than on a cross-zone run.

Travelling in the reverse direction, from Austin to Houston, covers the same 146 straight-line miles and essentially the same road distance, with a compass heading of roughly east-southeast instead of west-northwest. Small differences can appear by direction — one-way systems in each city centre, junction layouts and which side of a divided highway a service area sits on — but for planning purposes the pair is symmetric: the same figures, the same allowance for stops, and the same advice to check live conditions on the day.

Frequently Asked Questions

How far is Houston from Austin?

It is 146 miles in a straight line and 164 miles by road (measured via OpenStreetMap routing), as itemised in the comparison table above.

How long does it take to drive from Houston to Austin?

About 3 hr 7 min of driving in free-flowing conditions, before stops and delays. Add time for fuel, food and rest breaks on any real trip.

Why is the driving distance longer than the straight-line distance?

Because roads follow terrain, junctions and street patterns rather than the direct great-circle line, which adds 18 miles — about 12 percent — on this pair.

How This Page Was Calculated

Coordinates come from the U.S. Census Bureau Gazetteer files, straight-line distance from the haversine formula, and driving figures from OpenStreetMap routing via OSRM where a measured route is published, or from our documented estimate (straight line × 1.25, time at 50 mph) where it is not. The full method, including its limits, is set out on our methodology page, and the companion guide to straight-line versus driving distance explains the concepts in plain language.

Sources: Coordinates: U.S. Census Bureau Gazetteer files; driving data: OpenStreetMap/OSRM — retrieved October 2026.