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3815 SAPPHIRE LOOP, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

3 bed2 bath2,861 sqftBuilt 2008

Property at a Glance

This home is estimated between $541,591 and $707,356, with a best estimate of $599,078. That places the property below the L495414C - BORHO/MAYFIELD RANCH/SAPPHIRE LOOP median of $623,673, in a neighborhood that declined 8.0% over the past year.

Estimated Value Range

$541,591 $707,356
Best Estimate
$599,078
WCAD Value
$562,637
High Confidence

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

Based on 5 comparable properties in L495414C - BORHO/MAYFIELD RANCH/SAPPHIRE LOOP, this home's estimated market value is between $541,591 and $707,356. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3912 SAPPHIRE LOOP, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,521 sqft Built 2008
Raw Value $603,157
Adjusted Value $707,356

Adjusted +$104,199 for 340 sqft more living space. Net adjustment: +$104,199.

3929 SAPPHIRE LOOP, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,517 sqft Built 2007
Raw Value $491,656
Adjusted Value $599,078

Adjusted +$105,425 for 344 sqft more living space and +$1,997 for being newer. Net adjustment: +$107,422.

3920 SAPPHIRE LOOP, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 3 bath 2,496 sqft Built 2011
Raw Value $498,039
Adjusted Value $603,908

Adjusted +$111,861 for 365 sqft more living space and -$5,992 for being older. Net adjustment: +$105,869.

4112 SAPPHIRE LOOP, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 3 bath 3,208 sqft Built 2008
Raw Value $647,936
Adjusted Value $541,591

Adjusted -$106,345 for 347 sqft less living space. Net adjustment: -$106,345.

4100 SAPPHIRE LOOP, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,852 sqft Built 2007
Raw Value $559,535
Adjusted Value $564,290

Adjusted +$2,758 for 9 sqft more living space and +$1,997 for being newer. Net adjustment: +$4,755.

The Neighborhood

This home is valued 9.8% below the L495414C - BORHO/MAYFIELD RANCH/SAPPHIRE LOOP median of $623,673. That positions it competitively for buyers comparing within the neighborhood. Note that values in this subdivision declined 8.0% over the past year.

L495414C - BORHO/MAYFIELD RANCH/SAPPHIRE LOOP

typical
427 Properties
$623,673 Median Value
-8.0% YoY Change
1% Have Pool
100% Have Garage
This Home
$562,637
Median
$623,673

This home is -9.8% below the subdivision median.

Tax Analysis

The estimated annual property tax is $11,214 across all districts. With a homestead exemption claimed, that drops to $9,588 — saving $1,626 per year. That's $799 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
Leander ISDSchool1.0869%$6,115
Round RockCity0.3720%$2,093
Williamson CountyCounty0.3694%$2,079
Austin Community Collegespecial0.1034%$582
Williamson County FM/RdCounty0.0443%$249
Upper Brushy Creek WCIDWater0.0170%$96
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.9931%$11,214

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $599,078 would pay approximately $3,739 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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