📍 View location on OpenStreetMap (30.550380, -97.636810)
| Data Metric | Local Statistic |
|---|---|
| Postal / Zip Code | 78665 |
| Primary City | Round Rock |
| State / Province | TX |
| County | Williamson |
| Total Population | 66,171 |
| Population Density | 1,061.1 people/sq mi |
| Timezone | America/Chicago |
| Metric | ZIP 78665 | Williamson County records | TX records |
|---|---|---|---|
| Population estimate | 66,171 | 591,187 (sum) | 30,188,035 (sum) |
| Population Density | 1,061.1 /sq mi | -- | -- |
| County population rank | #2 of 18 | -- | -- |
| State population rank | #60 of 1,924 | -- | -- |
Regional sums combine the population estimates in the listed ZIP records; they are not official county or state population totals.
| ZIP Code | City | Distance | Population estimate |
|---|---|---|---|
| ZIP 78664 | Round Rock | 3.2 mi | 62,060 |
| ZIP 78681 | Round Rock | 5.0 mi | 56,691 |
| ZIP 78634 | Hutto | 5.6 mi | 46,413 |
| ZIP 78728 | Austin | 7.3 mi | 26,777 |
| ZIP 78660 | Pflugerville | 7.8 mi | 124,834 |
Data Sources & Methodology: Geographic coordinates and ZIP Code assignments are derived from underlying geographic and postal datasets. Note that ZIP Codes are USPS postal delivery areas, while Census ZCTAs are statistical approximation areas. Read full methodology →