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3820 SAPPHIRE LOOP, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

4 bed3 bath3,289 sqftBuilt 2011

Property at a Glance

This home is estimated between $678,752 and $1,081,173, with a best estimate of $741,068. That places the property above 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

$678,752 $1,081,173
Best Estimate
$741,068
WCAD Value
$626,835
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 $678,752 and $1,081,173. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3917 SAPPHIRE LOOP, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 3 bath 2,205 sqft Built 2011
Raw Value $638,861
Adjusted Value $971,073

Adjusted +$332,212 for 1,084 sqft more living space. Net adjustment: +$332,212.

4009 SAPPHIRE LOOP, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 3 bath 2,003 sqft Built 2011
Raw Value $687,055
Adjusted Value $1,081,173

Adjusted +$394,118 for 1,286 sqft more living space. Net adjustment: +$394,118.

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 $741,068

Adjusted +$243,029 for 793 sqft more living space. Net adjustment: +$243,029.

3815 SAPPHIRE LOOP, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,861 sqft Built 2008
Raw Value $562,637
Adjusted Value $699,797

Adjusted +$131,168 for 428 sqft more living space and +$5,992 for being newer. Net adjustment: +$137,160.

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 $678,752

Adjusted +$24,824 for 81 sqft more living space and +$5,992 for being newer. Net adjustment: +$30,816.

The Neighborhood

This home is in line with the L495414C - BORHO/MAYFIELD RANCH/SAPPHIRE LOOP median of $623,673. 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
$626,835
Median
$623,673

This home is +0.5% above the subdivision median.

Tax Analysis

The estimated annual property tax is $12,493 across all districts. With a homestead exemption claimed, that drops to $10,856 — saving $1,637 per year. That's $905 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%$6,813
Round RockCity0.3720%$2,332
Williamson CountyCounty0.3694%$2,316
Austin Community Collegespecial0.1034%$648
Williamson County FM/RdCounty0.0443%$278
Upper Brushy Creek WCIDWater0.0170%$107
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.9931%$12,493

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $741,068 would pay approximately $4,626 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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