Beta Williamson County, TX only — data and coverage are limited during early access.

3918 BONNIE LN, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed2 bath2,272 sqftBuilt 2003

Property at a Glance

This home is estimated between $372,475 and $501,512, with a best estimate of $423,229. 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

$372,475 $501,512
Best Estimate
$423,229
WCAD Value
$326,552
Low Confidence

Based on 5 comparable properties(1 in the same subdivision)

There are 5 comparable properties within range, but few are in R409599G - STONEY BROOK - ALL SECTIONS. The estimated range of $372,475 and $501,512 should be treated as a rough guide.

Comparable Properties (5)

3920 BONNIE LN, ROUND ROCK, TX 78665
0.01 mi 100% similar Same subdivision
3 bed 2 bath 1,989 sqft Built 2003
Raw Value $306,947
Adjusted Value $372,475

Adjusted +$65,528 for 283 sqft more living space. Net adjustment: +$65,528.

4 bed 2 bath 2,288 sqft Built 2005
Raw Value $496,994
Adjusted Value $501,512

Adjusted -$3,705 for 16 sqft less living space and +$8,223 for being newer. Net adjustment: +$4,518.

3 bed 2 bath 2,104 sqft Built 2005
Raw Value $374,248
Adjusted Value $421,371

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

3 bed 2 bath 2,073 sqft Built 2005
Raw Value $372,126
Adjusted Value $426,427

Adjusted +$46,078 for 199 sqft more living space and +$8,223 for being newer. Net adjustment: +$54,301.

3 bed 2 bath 2,130 sqft Built 2006
Raw Value $378,015
Adjusted Value $423,229

Adjusted +$32,880 for 142 sqft more living space and +$12,334 for being newer. Net adjustment: +$45,214.

The Neighborhood

This home is in line with the R409599G - STONEY BROOK - ALL SECTIONS median of $328,056. 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
$326,552
Median
$328,056

This home is -0.5% below the subdivision median.

Tax Analysis

The estimated annual property tax is $5,876 across all districts. With a homestead exemption claimed, that drops to $4,565 — saving $1,311 per year. That's $380 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%$2,916
Round RockCity0.3720%$1,215
Williamson CountyCounty0.3694%$1,206
Austin Community Collegespecial0.1034%$338
Williamson County FM/RdCounty0.0443%$145
Upper Brushy Creek WCIDWater0.0170%$56
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$5,876

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $423,229 would pay approximately $2,642 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.

View full property details