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4021 CASTLE CREEK, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

4 bed2 bath3,036 sqftBuilt 1998

Property at a Glance

This home is estimated between $532,145 and $1,102,709, with a best estimate of $914,225. That places the property above the L494500D - Vista Oaks Sec 5B Ph 2 & SEC 5C median of $449,628, in a neighborhood that declined 2.9% over the past year.

Estimated Value Range

$532,145 $1,102,709
Best Estimate
$914,225
WCAD Value
$529,119
Low Confidence

Based on 5 comparable properties(0 in the same subdivision)

There are 5 comparable properties within range, but none are in L494500D - Vista Oaks Sec 5B Ph 2 & SEC 5C. The estimated range of $532,145 and $1,102,709 should be treated as a rough guide.

Comparable Properties (5)

4 bed 2 bath 3,110 sqft Built 2000
Raw Value $572,254
Adjusted Value $544,314

Adjusted -$20,835 for 74 sqft less living space and -$7,105 for being older. Net adjustment: -$27,940.

3 bed 2 bath 3,097 sqft Built 2000
Raw Value $556,425
Adjusted Value $532,145

Adjusted -$17,175 for 61 sqft less living space and -$7,105 for being older. Net adjustment: -$24,280.

4 bed 3 bath 2,154 sqft Built 2001
Raw Value $860,722
Adjusted Value $1,098,397

Adjusted +$248,332 for 882 sqft more living space and -$10,657 for being older. Net adjustment: +$237,675.

4 bed 3 bath 2,219 sqft Built 2007
Raw Value $904,649
Adjusted Value $1,102,709

Adjusted +$230,031 for 817 sqft more living space and -$31,971 for being older. Net adjustment: +$198,060.

3 bed 2 bath 2,221 sqft Built 2014
Raw Value $741,595
Adjusted Value $914,225

Adjusted +$229,468 for 815 sqft more living space and -$56,838 for being older. Net adjustment: +$172,630.

The Neighborhood

This home is valued 17.7% above the L494500D - Vista Oaks Sec 5B Ph 2 & SEC 5C median of $449,628. With 904 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 2.9% over the past year.

L494500D - Vista Oaks Sec 5B Ph 2 & SEC 5C

above average
904 Properties
$449,628 Median Value
-2.9% YoY Change
1% Have Pool
99% Have Garage
This Home
$529,119
Median
$449,628

This home is +17.7% above the subdivision median.

Tax Analysis

The estimated annual property tax is $10,234 across all districts. With a homestead exemption claimed, that drops to $8,614 — saving $1,620 per year. That's $718 per month a buyer should budget. The assessed value increased roughly in line with the neighborhood, so a tax protest is unlikely to yield significant savings.

Tax Districts

DistrictTypeRateAnnual Amount
Leander ISDSchool1.0869%$5,751
Williamson CountyCounty0.3694%$1,955
Vista Oaks MUDMUD0.2131%$1,128
Austin Community Collegespecial0.1034%$547
Williamson County ESD #9 - Round RockESD0.0999%$529
Williamson County FM/RdCounty0.0443%$235
Upper Brushy Creek WCIDWater0.0170%$90
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.9341%$10,234

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $914,225 would pay approximately $5,707 per month (principal and interest only, excluding taxes and insurance).

Data sourced from Williamson County Appraisal District (WCAD), Texas Education Agency (TEA), and Federal Reserve Economic Data (FRED). Assessment values reflect the appraisal district's estimate, not market sale prices. Report generated 4/18/2026.

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