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18 VALLEY CREEK DR, ROUND ROCK, TX 78664

ROUND ROCK, 78664 — williamson County

4 bed2 bath1,152 sqftBuilt 1980

Property at a Glance

This home is estimated between $264,937 and $451,086, with a best estimate of $394,242. That places the property below the R575583D - RR Rual Sub 122 & Gattis School Rd Area median of $734,399, in a neighborhood that appreciated 3.8% over the past year.

Estimated Value Range

$264,937 $451,086
Best Estimate
$394,242
WCAD Value
$483,789
Low Confidence

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

There are 5 comparable properties within range, but few are in R575583D - RR Rual Sub 122 & Gattis School Rd Area. The estimated range of $264,937 and $451,086 should be treated as a rough guide.

Comparable Properties (5)

14 VALLEY CREEK DR, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,427 sqft Built 1984
Raw Value $539,541
Adjusted Value $451,086

Adjusted -$88,505 for 275 sqft less living space and +$50 for being newer. Net adjustment: -$88,455.

16 VALLEY CREEK DR, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,610 sqft Built 1984
Raw Value $506,501
Adjusted Value $359,151

Adjusted -$147,400 for 458 sqft less living space and +$50 for being newer. Net adjustment: -$147,350.

4 bed 2 bath 1,076 sqft Built 1993
Raw Value $369,619
Adjusted Value $394,242

Adjusted +$24,459 for 76 sqft more living space and +$164 for being newer. Net adjustment: +$24,623.

3 bed 2 bath 1,268 sqft Built 1986
Raw Value $302,195
Adjusted Value $264,937

Adjusted -$37,333 for 116 sqft less living space and +$75 for being newer. Net adjustment: -$37,258.

3 bed 2 bath 1,064 sqft Built 1972
Raw Value $398,043
Adjusted Value $426,263

Adjusted +$28,321 for 88 sqft more living space and -$101 for being older. Net adjustment: +$28,220.

The Neighborhood

This home is valued 34.1% below the R575583D - RR Rual Sub 122 & Gattis School Rd Area median of $734,399. That positions it competitively for buyers comparing within the neighborhood. The neighborhood appreciated 3.8% over the past year.

R575583D - RR Rual Sub 122 & Gattis School Rd Area

below average
213 Properties
$734,399 Median Value
+3.8% YoY Change
4% Have Pool
68% Have Garage
This Home
$483,789
Median
$734,399

This home is -34.1% below the subdivision median.

Tax Analysis

The estimated annual property tax is $7,388 across all districts. With a homestead exemption claimed, that drops to $6,049 — saving $1,339 per year. That's $504 per month a buyer should budget. The assessed value increased +9.5% vs the subdivision average of +3.8%. This above-average increase gives a protest opportunity score of 44 out of 100 — it may be worth challenging the appraisal.

Tax Districts

DistrictTypeRateAnnual Amount
Round Rock ISDSchool0.8931%$4,321
Williamson CountyCounty0.3694%$1,787
Austin Community Collegespecial0.1034%$500
Williamson County ESD #9 - Round RockESD0.0999%$483
Williamson County FM/RdCounty0.0443%$214
Upper Brushy Creek WCIDWater0.0170%$82
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.5272%$7,388
44 / 100

Moderate opportunity to protest.

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $394,242 would pay approximately $2,461 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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