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100 GRAND ISLE DR, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed2 bath1,831 sqftBuilt 2003

Property at a Glance

This home is estimated between $267,301 and $358,787, with a best estimate of $330,431. That places the property below the R434598G - Chandler Creek median of $342,930, in a neighborhood that declined 6.7% over the past year.

Estimated Value Range

$267,301 $358,787
Best Estimate
$330,431
WCAD Value
$379,279
Medium Confidence

Based on 5 comparable properties(4 in the same subdivision)

Based on 5 comparable properties (4 in the same subdivision, 1 nearby), the estimated range is $267,301 and $358,787. More comparables in the same subdivision would strengthen this estimate.

Comparable Properties (5)

3 bed 2 bath 1,932 sqft Built 1999
Raw Value $378,685
Adjusted Value $358,787

Adjusted -$18,975 for 101 sqft less living space and -$923 for being older. Net adjustment: -$19,898.

223 GRAND ISLE DR, ROUND ROCK, TX 78665
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,293 sqft Built 2002
Raw Value $354,329
Adjusted Value $267,301

Adjusted -$86,797 for 462 sqft less living space and -$231 for being older. Net adjustment: -$87,028.

211 GRAND ISLE DR, ROUND ROCK, TX 78665
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,812 sqft Built 2002
Raw Value $330,264
Adjusted Value $333,603

Adjusted +$3,570 for 19 sqft more living space and -$231 for being older. Net adjustment: +$3,339.

212 GRAND ISLE DR, ROUND ROCK, TX 78665
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,812 sqft Built 2002
Raw Value $333,531
Adjusted Value $305,134

Adjusted +$3,570 for 19 sqft more living space and -$231 for being older and -$31,736 for no pool. Net adjustment: -$28,397.

206 GRAND ISLE DR, ROUND ROCK, TX 78665
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,815 sqft Built 2002
Raw Value $327,656
Adjusted Value $330,431

Adjusted +$3,006 for 16 sqft more living space and -$231 for being older. Net adjustment: +$2,775.

The Neighborhood

This home is valued 10.6% above the R434598G - Chandler Creek median of $342,930. With 709 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 6.7% over the past year.

R434598G - Chandler Creek

typical
709 Properties
$342,930 Median Value
-6.7% YoY Change
1% Have Pool
100% Have Garage
This Home
$379,279
Median
$342,930

This home is +10.6% above the subdivision median.

Tax Analysis

The estimated annual property tax is $6,873 across all districts. With a homestead exemption claimed, that drops to $5,552 — saving $1,321 per year. That's $463 per month a buyer should budget. The assessed value increased +3.0% vs the subdivision average of -6.7%. This above-average increase gives a protest opportunity score of 49 out of 100 — it may be worth challenging the appraisal.

Tax Districts

DistrictTypeRateAnnual Amount
Round Rock ISDSchool0.8931%$3,387
Williamson CountyCounty0.3694%$1,401
Meadows of Chandler Creek MUDMUD0.2849%$1,081
Austin Community Collegespecial0.1034%$392
Williamson County ESD #9 - Round RockESD0.0999%$379
Williamson County FM/RdCounty0.0443%$168
Upper Brushy Creek WCIDWater0.0170%$64
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.8121%$6,873
49 / 100

Moderate opportunity to protest.

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $330,431 would pay approximately $2,063 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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