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3940 SAPPHIRE LOOP, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

4 bed3 bath1,921 sqftBuilt 2007

Property at a Glance

This home is estimated between $358,973 and $686,536, with a best estimate of $595,958. 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

$358,973 $686,536
Best Estimate
$595,958
WCAD Value
$626,191
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 $358,973 and $686,536. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3944 SAPPHIRE LOOP, ROUND ROCK, TX 78681
0.01 mi 100% similar Same subdivision
4 bed 3 bath 1,645 sqft Built 2006
Raw Value $599,954
Adjusted Value $686,536

Adjusted +$84,585 for 276 sqft more living space and +$1,997 for being newer. Net adjustment: +$86,582.

3936 SAPPHIRE LOOP, ROUND ROCK, TX 78681
0.02 mi 100% similar Same subdivision
4 bed 3 bath 1,972 sqft Built 2007
Raw Value $620,819
Adjusted Value $605,189

Adjusted -$15,630 for 51 sqft less living space. Net adjustment: -$15,630.

3952 SAPPHIRE LOOP, ROUND ROCK, TX 78681
0.04 mi 100% similar Same subdivision
4 bed 3 bath 1,950 sqft Built 2004
Raw Value $592,854
Adjusted Value $589,958

Adjusted -$8,888 for 29 sqft less living space and +$5,992 for being newer. Net adjustment: -$2,896.

3956 SAPPHIRE LOOP, ROUND ROCK, TX 78681
0.05 mi 100% similar Same subdivision
3 bed 2 bath 2,321 sqft Built 2007
Raw Value $481,560
Adjusted Value $358,973

Adjusted -$122,587 for 400 sqft less living space. Net adjustment: -$122,587.

3964 SAPPHIRE LOOP, ROUND ROCK, TX 78681
0.07 mi 100% similar Same subdivision
4 bed 3 bath 1,934 sqft Built 2007
Raw Value $599,942
Adjusted Value $595,958

Adjusted -$3,984 for 13 sqft less living space. Net adjustment: -$3,984.

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
$626,191
Median
$623,673

This home is +0.4% above the subdivision median.

Tax Analysis

The estimated annual property tax is $12,480 across all districts. With a homestead exemption claimed, that drops to $10,843 — saving $1,637 per year. That's $904 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%$6,806
Round RockCity0.3720%$2,329
Williamson CountyCounty0.3694%$2,313
Austin Community Collegespecial0.1034%$647
Williamson County FM/RdCounty0.0443%$278
Upper Brushy Creek WCIDWater0.0170%$106
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.9931%$12,480

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $595,958 would pay approximately $3,720 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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