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21 HIDDEN ACRES DR, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

4 bed2 bath1,017 sqftBuilt 1979

Property at a Glance

This home is estimated between $225,616 and $554,574, with a best estimate of $278,551. That places the property below the R427578G - Hidden Acres & Sec 2 median of $412,870, in a neighborhood that declined 4.2% over the past year.

Estimated Value Range

$225,616 $554,574
Best Estimate
$278,551
WCAD Value
$355,158
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 $225,616 and $554,574. More comparables in the same subdivision would strengthen this estimate.

Comparable Properties (5)

4 bed 2 bath 968 sqft Built 1985
Raw Value $616,572
Adjusted Value $554,574

Adjusted +$10,421 for 49 sqft more living space and -$72,419 for being older. Net adjustment: -$61,998.

12 HIDDEN ACRES DR, ROUND ROCK, TX 78665
0.00 mi 100% similar Same subdivision
4 bed 2 bath 1,411 sqft Built 1981
Raw Value $412,870
Adjusted Value $304,939

Adjusted -$83,791 for 394 sqft less living space and -$24,140 for being older. Net adjustment: -$107,931.

11 HIDDEN ACRES DR, ROUND ROCK, TX 78665
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,477 sqft Built 1977
Raw Value $299,303
Adjusted Value $225,616

Adjusted -$97,827 for 460 sqft less living space and +$24,140 for being newer. Net adjustment: -$73,687.

16 HIDDEN ACRES DR, ROUND ROCK, TX 78665
0.00 mi 99% similar Same subdivision
3 bed 2 bath 1,485 sqft Built 1977
Raw Value $308,754
Adjusted Value $233,366

Adjusted -$99,528 for 468 sqft less living space and +$24,140 for being newer. Net adjustment: -$75,388.

18 HIDDEN ACRES DR, ROUND ROCK, TX 78665
0.00 mi 99% similar Same subdivision
4 bed 2 bath 1,828 sqft Built 1977
Raw Value $426,884
Adjusted Value $278,551

Adjusted -$172,473 for 811 sqft less living space and +$24,140 for being newer. Net adjustment: -$148,333.

The Neighborhood

This home is valued 14.0% below the R427578G - Hidden Acres & Sec 2 median of $412,870. That positions it competitively for buyers comparing within the neighborhood. Note that values in this subdivision declined 4.2% over the past year.

R427578G - Hidden Acres & Sec 2

typical
19 Properties
$412,870 Median Value
-4.2% YoY Change
26% Have Pool
84% Have Garage
This Home
$355,158
Median
$412,870

This home is -14.0% below the subdivision median.

Tax Analysis

The estimated annual property tax is $5,424 across all districts. With a homestead exemption claimed, that drops to $4,108 — saving $1,316 per year. That's $342 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%$3,172
Williamson CountyCounty0.3694%$1,312
Austin Community Collegespecial0.1034%$367
Williamson County ESD #9 - Round RockESD0.0999%$355
Williamson County FM/RdCounty0.0443%$157
Upper Brushy Creek WCIDWater0.0170%$60
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.5272%$5,424

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $278,551 would pay approximately $1,739 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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