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3508 SHELLCASTLE LN, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

4 bed2 bath1,874 sqftBuilt 2007

Property at a Glance

This home is estimated between $341,381 and $603,529, with a best estimate of $406,179. 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

$341,381 $603,529
Best Estimate
$406,179
WCAD Value
$547,080
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 $341,381 and $603,529. 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 $406,179

Adjusted -$8,085 for 29 sqft less living space. Net adjustment: -$8,085.

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 $603,529

Adjusted +$27,321 for 98 sqft more living space. Net adjustment: +$27,321.

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 $341,381

Adjusted -$129,916 for 466 sqft less living space and +$271 for being newer. Net adjustment: -$129,645.

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 $425,924

Adjusted -$14,497 for 52 sqft less living space and -$271 for being older. Net adjustment: -$14,768.

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 $372,544

Adjusted -$43,770 for 157 sqft less living space. Net adjustment: -$43,770.

The Neighborhood

This home is valued 7.1% 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
$547,080
Median
$510,992

This home is +7.1% above the subdivision median.

Tax Analysis

The estimated annual property tax is $9,843 across all districts. With a homestead exemption claimed, that drops to $8,492 — saving $1,351 per year. That's $708 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%$4,886
Round RockCity0.3720%$2,035
Williamson CountyCounty0.3694%$2,021
Austin Community Collegespecial0.1034%$566
Williamson County FM/RdCounty0.0443%$243
Upper Brushy Creek WCIDWater0.0170%$93
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$9,843

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $406,179 would pay approximately $2,535 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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