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3919 BONNIE LN, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed2 bath1,280 sqftBuilt 2003

Property at a Glance

This home is estimated between $110,362 and $458,453, with a best estimate of $284,506. That places the property below the R409599G - STONEY BROOK - ALL SECTIONS median of $328,056, in a neighborhood that declined 4.7% over the past year.

Estimated Value Range

$110,362 $458,453
Best Estimate
$284,506
WCAD Value
$271,265
Low Confidence

Based on 5 comparable properties(2 in the same subdivision)

There are 5 comparable properties within range, but few are in R409599G - STONEY BROOK - ALL SECTIONS. The estimated range of $110,362 and $458,453 should be treated as a rough guide.

Comparable Properties (5)

3917 BONNIE LN, ROUND ROCK, TX 78665
0.01 mi 100% similar Same subdivision
3 bed 2 bath 1,804 sqft Built 2003
Raw Value $324,184
Adjusted Value $202,854

Adjusted -$121,330 for 524 sqft less living space. Net adjustment: -$121,330.

3 bed 2 bath 1,213 sqft Built 2006
Raw Value $430,605
Adjusted Value $458,453

Adjusted +$15,514 for 67 sqft more living space and +$12,334 for being newer. Net adjustment: +$27,848.

3 bed 2 bath 1,173 sqft Built 2005
Raw Value $414,723
Adjusted Value $447,721

Adjusted +$24,775 for 107 sqft more living space and +$8,223 for being newer. Net adjustment: +$32,998.

3921 BONNIE LN, ROUND ROCK, TX 78665
0.01 mi 100% similar Same subdivision
3 bed 2 bath 2,245 sqft Built 2003
Raw Value $333,804
Adjusted Value $110,362

Adjusted -$223,442 for 965 sqft less living space. Net adjustment: -$223,442.

3 bed 2 bath 1,473 sqft Built 2005
Raw Value $320,971
Adjusted Value $284,506

Adjusted -$44,688 for 193 sqft less living space and +$8,223 for being newer. Net adjustment: -$36,465.

The Neighborhood

This home is valued 17.3% below the R409599G - STONEY BROOK - ALL SECTIONS median of $328,056. That positions it competitively for buyers comparing within the neighborhood. Note that values in this subdivision declined 4.7% over the past year.

R409599G - STONEY BROOK - ALL SECTIONS

below average
197 Properties
$328,056 Median Value
-4.7% YoY Change
0% Have Pool
100% Have Garage
This Home
$271,265
Median
$328,056

This home is -17.3% below the subdivision median.

Tax Analysis

The estimated annual property tax is $4,881 across all districts. With a homestead exemption claimed, that drops to $3,580 — saving $1,301 per year. That's $298 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%$2,423
Round RockCity0.3720%$1,009
Williamson CountyCounty0.3694%$1,002
Austin Community Collegespecial0.1034%$280
Williamson County FM/RdCounty0.0443%$120
Upper Brushy Creek WCIDWater0.0170%$46
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$4,881

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $284,506 would pay approximately $1,776 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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