ZIP Code 78664
Round Rock · Williamson, Texas
78664 is the ZIP code of Round Rock in Williamson, Texas, United States.
- ZIP Code
- 78664
- County
- Williamson
- State
- Texas
- Country
- United States
Place with ZIP code 78664
| Place | County | Location |
|---|---|---|
| Round Rock | Williamson | 30.515, -97.668 |
Near Austin
The nearest major city is Austin, about 28 km away.
Nearby ZIP codes
Frequently asked questions
Which places use ZIP code 78664?
Round Rock.
Which county and state is 78664 in?
Williamson, Texas, United States.
What is the nearest major city to 78664?
Austin, about 28 km away.
Source: GeoNames postal codes (CC BY 4.0), geonames.org, retrieved 2026-10-22. Place coordinates are approximate. Check with the national postal service before sending anything valuable.