Williamson
Source:
Texas
Williamson is a major-metro county in Texas with 20 ZIP codes, 434,421 people, and top-decile household income among US counties. All data is sourced from the U.S. Census Bureau American Community Survey (ACS) 2023 5-Year Estimates.
National county placement
According to ACS 5-Year Estimates, Williamson, TX sits among US counties with a top-decile household income, on a major-metro county population base, across a multi-ZIP patchwork.
- Top 5%
- household income vs 3,210 US counties
- 434,421
- combined ZIP population
- 20
- USPS ZIP codes covered
- $107,077
- avg ZIP median income
Income percentile ranks this county's average ZIP median household income against 3,210 US counties with ACS income on at least one ZIP.
Williamson lands in the national county income distribution as top-decile household income on major-metro county footing (FIPS 48491, 20 ZIPs, combined population 434,421). Sort the ZIP table by population before treating the county mean as uniform.
High-income counties with wide ZIP mosaics hide sharp internal gradients. The densest ZIP here is 78613 (Cedar Park) with 65,099 residents - open it beside a thin rural code from the table before treating the county mean as uniform. HUD Fair Market Rents and FBI county tables attach to FIPS 48491, so scorecards stay county-keyed while household income stays ZIP-keyed.
Save two ZIPs from the table into your shortlist, then open a compare link - that is the return path a static county summary cannot replace. All figures here come from Census ACS 2023 5-Year Estimates and USPS ZCTA files.
20
Total ZIPs
434,421
Total Population
ZIP Codes in Williamson
Side-by-side: Compare 78613 vs 78664 →
| ZIP Code | City | Population | Density |
|---|---|---|---|
| 78613 | Cedar Park | 65,099 | 893 |
| 78664 | Round Rock | 52,932 | 1,233 |
| 78681 | Round Rock | 50,606 | 899 |
| 78641 | Leander | 44,295 | 135 |
| 78665 | Round Rock | 35,985 | 741 |
| 78729 | Austin | 27,108 | 1,140 |
| 78626 | Georgetown | 25,996 | 108 |
| 78628 | Georgetown | 23,727 | 125 |
| 78634 | Hutto | 22,791 | 138 |
| 78717 | Austin | 22,538 | 674 |
| 78633 | Georgetown | 19,349 | 91 |
| 76574 | Taylor | 17,661 | 48 |
| 78642 | Liberty Hill | 9,467 | 37 |
| 76527 | Florence | 4,058 | 12 |
| 76537 | Jarrell | 3,870 | 28 |
| 76511 | Bartlett | 3,317 | 16 |
| 76530 | Granger | 2,540 | 11 |
| 76578 | Thrall | 1,766 | 9 |
| 78615 | Coupland | 1,290 | 10 |
| 76573 | Schwertner | 26 | 11 |
Frequently Asked Questions
What is the population of Williamson?
Williamson has a total population of 434,421 across 20 ZIP codes, based on U.S. Census Bureau ACS 2023 data.
What ZIP codes are in Williamson?
Williamson includes 20 ZIP codes: 78613, 78664, 78681, 78641, 78665, 78729, 78626, 78628, 78634, 78717, and more.