Williamson County, Texas ZIP Codes
- ZIP records
19 - Cities represented
14 - Sum of listed ZIP population estimates
591,187
Population sum includes positive estimates in these ZIP records; it is not an official county population.
Top ZIP Codes by Population
| Rank | ZIP Code | City | Population estimate |
|---|---|---|---|
| 1 | 78613 | Cedar Park | 89,956 |
| 2 | 78665 | Round Rock | 66,171 |
| 3 | 78664 | Round Rock | 62,060 |
| 4 | 78681 | Round Rock | 56,691 |
| 5 | 78628 | Georgetown | 50,822 |
| 6 | 78626 | Georgetown | 48,072 |
| 7 | 78634 | Hutto | 46,413 |
| 8 | 78717 | Austin | 37,262 |
| 9 | 78729 | Austin | 30,460 |
| 10 | 78633 | Georgetown | 29,309 |
Cities in Williamson County
- Austin
- Cedar Park
- Coupland
- Florence
- Georgetown
- Granger
- Hutto
- Jarrell
- Liberty Hill
- Round Rock
- Schwertner
- Taylor
- Thrall
- Weir
ZIP Directory
- ZIP 76527
- ZIP 76530
- ZIP 76537
- ZIP 76573
- ZIP 76574
- ZIP 76578
- ZIP 78613
- ZIP 78615
- ZIP 78626
- ZIP 78628
- ZIP 78633
- ZIP 78634
- ZIP 78642
- ZIP 78664
- ZIP 78665
- ZIP 78674
- ZIP 78681
- ZIP 78717
- ZIP 78729
Methodology: Records are grouped by the source file's listed county and state. Population sums add positive ZIP-level estimates and are not official county totals; city counts use distinct city labels in the source.