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509 HILLSIDE DR, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

4 bed2 bath1,662 sqftBuilt 1979

Property at a Glance

This home is estimated between $363,942 and $562,206, with a best estimate of $411,478. That places the property above the R210480H - Brushy Creek median of $296,542, in a neighborhood that declined 14.6% over the past year.

Estimated Value Range

$363,942 $562,206
Best Estimate
$411,478
WCAD Value
$310,013
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 $363,942 and $562,206. More comparables in the same subdivision would strengthen this estimate.

Comparable Properties (5)

3609 CORNERSTONE, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,269 sqft Built 1982
Raw Value $290,537
Adjusted Value $373,364

Adjusted +$87,647 for 393 sqft more living space and -$4,820 for being older. Net adjustment: +$82,827.

3115 FREEMONT ST, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,303 sqft Built 1984
Raw Value $347,567
Adjusted Value $419,598

Adjusted +$80,064 for 359 sqft more living space and -$8,033 for being older. Net adjustment: +$72,031.

4 bed 2 bath 1,657 sqft Built 1978
Raw Value $559,484
Adjusted Value $562,206

Adjusted +$1,115 for 5 sqft more living space and +$1,607 for being newer. Net adjustment: +$2,722.

4001 HILLSIDE DR, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,133 sqft Built 1979
Raw Value $293,501
Adjusted Value $411,478

Adjusted +$117,977 for 529 sqft more living space. Net adjustment: +$117,977.

2901 MONUMENT DR, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,212 sqft Built 1982
Raw Value $268,403
Adjusted Value $363,942

Adjusted +$100,359 for 450 sqft more living space and -$4,820 for being older. Net adjustment: +$95,539.

The Neighborhood

This home is valued 4.5% above the R210480H - Brushy Creek median of $296,542. With 871 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 14.6% over the past year.

R210480H - Brushy Creek

typical
871 Properties
$296,542 Median Value
-14.6% YoY Change
2% Have Pool
94% Have Garage
This Home
$310,013
Median
$296,542

This home is +4.5% above the subdivision median.

Tax Analysis

The estimated annual property tax is $5,934 across all districts. With a homestead exemption claimed, that drops to $4,626 — saving $1,308 per year. That's $386 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%$2,769
Brushy Creek MUDMUD0.3868%$1,199
Williamson CountyCounty0.3694%$1,145
Austin Community Collegespecial0.1034%$321
Williamson County ESD #2 - Sam Bass VFDESD0.1000%$310
Williamson County FM/RdCounty0.0443%$137
Upper Brushy Creek WCIDWater0.0170%$53
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.9141%$5,934

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $411,478 would pay approximately $2,568 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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