ZIP code · Round Rock · Texas · United States
ZIP code 78664 — Round Rock
ZIP code 78664 serves Round Rock, Texas.
- Postal code
- 78664Single source Value from one source, not cross-checked.
- City
- Round Rock
- County
- Williamson FIPS 48491
- State
- Texas
- Country
- United States
- Coordinates
- 30.5145, -97.6680 — precision precise (locality)
View on OpenStreetMap - Population
- 62,272 (ZCTA, ACS 5-year)
- Population density
- 3,748 / sq mi
- Land area
- 16.6 sq mi (43 km²) (ZCTA, ACS 5-year)
- Median household income
- $85,919
- Per-capita income
- $41,683
- Median age
- 34.8
- Households
- 23,299
- Housing units
- 24,259
- Median home value
- $317,400
- Median gross rent
- $1,645 / month
- Congressional districts
- TX-17 (also TX-31) (119th Congress)
- USDA hardiness zone
- 9a (20 to 25 °F)Planting / growing zone from the 2023 USDA Plant Hardiness Zone Map: average annual extreme minimum temperature, 1991–2020.
- Time zone
- America/Chicago (UTC−6 / UTC−5 DST)
Tools: compare 78664 with another ZIP · ZIPs within 25 miles · distance from 78664
Map of ZIP code 78664
Climate — monthly normals
Warmest month Aug (avg high 96°F), coldest Jan (avg low 38°F).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 60 | 65 | 72 | 79 | 84 | 92 | 96 | 96 | 89 | 80 | 69 | 61 |
| Avg low °F | 38 | 41 | 48 | 55 | 64 | 70 | 73 | 72 | 67 | 57 | 47 | 39 |
| Precip in | 2.6 | 2.0 | 3.0 | 2.3 | 4.1 | 4.4 | 2.8 | 2.3 | 3.4 | 4.6 | 2.8 | 2.8 |
NOAA 1991–2020 climate normals from the nearest station: AUSTIN GREAT HILLS (9.1 mi) · NOAA NCEI
Places in ZIP 78664
- 19 schools
- 10 hospitals & clinics
- 4 doctors & dentists
- 10 pharmacies
- 8 supermarkets
- 93 restaurants & cafés
- 10 bars & pubs
- 35 parks
- 55 playgrounds
- 13 gyms & sports centres
- 1 libraries
- 3 post offices
- 15 places of worship
- 11 banks
- 30 gas stations
- 3 police & fire stations
Places mapped inside this ZIP’s ZCTA area in OpenStreetMap. OSM is community-maintained: counts reflect what has been mapped, and completeness varies by area — treat them as at-least figures. © OpenStreetMap contributors (ODbL) · Methodology
About this page
US ZIP codes have five digits. They are postal routing areas, not administrative boundaries: a ZIP can span more than one city or county, and the city shown is the primary USPS name for that code.
GeoNames · U.S. Census Bureau (ACS) · U.S. Census Bureau · NOAA NCEI · usda-phzm. Data generated on 2026-08-21. Methodology · Report an error on this page