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3921 BONNIE LN, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed2 bath2,245 sqftBuilt 2003

Property at a Glance

This home is estimated between $418,595 and $486,192, with a best estimate of $442,112. That places the property above the R409599G - STONEY BROOK - ALL SECTIONS median of $328,056, in a neighborhood that declined 4.7% over the past year.

Estimated Value Range

$418,595 $486,192
Best Estimate
$442,112
WCAD Value
$333,804
Medium Confidence

Based on 5 comparable properties(3 in the same subdivision)

Based on 5 comparable properties (3 in the same subdivision, 2 nearby), the estimated range is $418,595 and $486,192. More comparables in the same subdivision would strengthen this estimate.

Comparable Properties (5)

1516 TONIA LOOP, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,725 sqft Built 2007
Raw Value $308,945
Adjusted Value $445,794

Adjusted +$120,404 for 520 sqft more living space and +$16,445 for being newer. Net adjustment: +$136,849.

3917 BONNIE LN, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,804 sqft Built 2003
Raw Value $324,184
Adjusted Value $426,296

Adjusted +$102,112 for 441 sqft more living space. Net adjustment: +$102,112.

3925 BONNIE LN, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,577 sqft Built 2003
Raw Value $331,519
Adjusted Value $486,192

Adjusted +$154,673 for 668 sqft more living space. Net adjustment: +$154,673.

3 bed 2 bath 2,130 sqft Built 2005
Raw Value $407,261
Adjusted Value $442,112

Adjusted +$26,628 for 115 sqft more living space and +$8,223 for being newer. Net adjustment: +$34,851.

3 bed 2 bath 2,077 sqft Built 2005
Raw Value $371,472
Adjusted Value $418,595

Adjusted +$38,900 for 168 sqft more living space and +$8,223 for being newer. Net adjustment: +$47,123.

The Neighborhood

This home is valued 1.8% above the R409599G - STONEY BROOK - ALL SECTIONS median of $328,056. With 197 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 4.7% over the past year.

R409599G - STONEY BROOK - ALL SECTIONS

typical
197 Properties
$328,056 Median Value
-4.7% YoY Change
0% Have Pool
100% Have Garage
This Home
$333,804
Median
$328,056

This home is +1.8% above the subdivision median.

Tax Analysis

The estimated annual property tax is $6,006 across all districts. With a homestead exemption claimed, that drops to $4,694 — saving $1,312 per year. That's $391 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
Round Rock ISDSchool0.8931%$2,981
Round RockCity0.3720%$1,242
Williamson CountyCounty0.3694%$1,233
Austin Community Collegespecial0.1034%$345
Williamson County FM/RdCounty0.0443%$148
Upper Brushy Creek WCIDWater0.0170%$57
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$6,006

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $442,112 would pay approximately $2,760 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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