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3520 SHELLCASTLE LN, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

4 bed3 bath1,760 sqftBuilt 2006

Property at a Glance

This home is estimated between $340,491 and $571,476, with a best estimate of $392,905. That places the property below the L498506D - VILLAGE AT MAYFIELD median of $510,992, in a neighborhood that declined 5.8% over the past year.

Estimated Value Range

$340,491 $571,476
Best Estimate
$392,905
WCAD Value
$578,200
High Confidence

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

Based on 5 comparable properties in L498506D - VILLAGE AT MAYFIELD, this home's estimated market value is between $340,491 and $571,476. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3504 SHELLCASTLE LN, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,903 sqft Built 2007
Raw Value $414,264
Adjusted Value $374,126

Adjusted -$39,867 for 143 sqft less living space and -$271 for being older. Net adjustment: -$40,138.

3513 SHELLCASTLE LN, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 2 bath 1,776 sqft Built 2007
Raw Value $576,208
Adjusted Value $571,476

Adjusted -$4,461 for 16 sqft less living space and -$271 for being older. Net adjustment: -$4,732.

3532 SHELLCASTLE LN, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 2 bath 1,926 sqft Built 2008
Raw Value $440,692
Adjusted Value $393,872

Adjusted -$46,279 for 166 sqft less living space and -$541 for being older. Net adjustment: -$46,820.

3505 SHELLCASTLE LN, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,031 sqft Built 2007
Raw Value $416,314
Adjusted Value $340,491

Adjusted -$75,552 for 271 sqft less living space and -$271 for being older. Net adjustment: -$75,823.

3501 SHELLCASTLE LN, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 2 bath 2,333 sqft Built 2007
Raw Value $552,922
Adjusted Value $392,905

Adjusted -$159,746 for 573 sqft less living space and -$271 for being older. Net adjustment: -$160,017.

The Neighborhood

This home is valued 13.2% above the L498506D - VILLAGE AT MAYFIELD median of $510,992. With 696 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 5.8% over the past year.

L498506D - VILLAGE AT MAYFIELD

typical
696 Properties
$510,992 Median Value
-5.8% YoY Change
1% Have Pool
100% Have Garage
This Home
$578,200
Median
$510,992

This home is +13.2% above the subdivision median.

Tax Analysis

The estimated annual property tax is $10,403 across all districts. With a homestead exemption claimed, that drops to $9,046 — saving $1,357 per year. That's $754 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%$5,164
Round RockCity0.3720%$2,151
Williamson CountyCounty0.3694%$2,136
Austin Community Collegespecial0.1034%$598
Williamson County FM/RdCounty0.0443%$256
Upper Brushy Creek WCIDWater0.0170%$98
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$10,403

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $392,905 would pay approximately $2,453 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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