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3516 SHELLCASTLE LN, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

4 bed2 bath1,942 sqftBuilt 2007

Property at a Glance

This home is estimated between $360,339 and $622,487, with a best estimate of $425,137. 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

$360,339 $622,487
Best Estimate
$425,137
WCAD Value
$609,533
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 $360,339 and $622,487. 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 $425,137

Adjusted +$10,873 for 39 sqft more living space. Net adjustment: +$10,873.

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 $622,487

Adjusted +$46,279 for 166 sqft more living space. Net adjustment: +$46,279.

3525 SHELLCASTLE LN, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,340 sqft Built 2006
Raw Value $471,026
Adjusted Value $360,339

Adjusted -$110,958 for 398 sqft less living space and +$271 for being newer. Net adjustment: -$110,687.

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 $444,882

Adjusted +$4,461 for 16 sqft more living space and -$271 for being older. Net adjustment: +$4,190.

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 $391,502

Adjusted -$24,812 for 89 sqft less living space. Net adjustment: -$24,812.

The Neighborhood

This home is valued 19.3% 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

above average
696 Properties
$510,992 Median Value
-5.8% YoY Change
1% Have Pool
100% Have Garage
This Home
$609,533
Median
$510,992

This home is +19.3% above the subdivision median.

Tax Analysis

The estimated annual property tax is $10,967 across all districts. With a homestead exemption claimed, that drops to $9,604 — saving $1,363 per year. That's $800 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%$5,444
Round RockCity0.3720%$2,267
Williamson CountyCounty0.3694%$2,252
Austin Community Collegespecial0.1034%$630
Williamson County FM/RdCounty0.0443%$270
Upper Brushy Creek WCIDWater0.0170%$104
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$10,967

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $425,137 would pay approximately $2,654 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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