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3900 SAPPHIRE LOOP, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

3 bed2 bath2,523 sqftBuilt 2008

Property at a Glance

This home is estimated between $459,051 and $730,326, with a best estimate of $500,322. 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

$459,051 $730,326
Best Estimate
$500,322
WCAD Value
$498,198
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 $459,051 and $730,326. 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 $603,770

Adjusted +$613 for 2 sqft more living space. Net adjustment: +$613.

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 $730,326

Adjusted +$97,457 for 318 sqft more living space and -$5,992 for being older. Net adjustment: +$91,465.

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 $495,492

Adjusted +$1,839 for 6 sqft more living space and +$1,997 for being newer. Net adjustment: +$3,836.

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 $500,322

Adjusted +$8,275 for 27 sqft more living space and -$5,992 for being older. Net adjustment: +$2,283.

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 $459,051

Adjusted -$103,586 for 338 sqft less living space. Net adjustment: -$103,586.

The Neighborhood

This home is valued 20.1% 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

below average
427 Properties
$623,673 Median Value
-8.0% YoY Change
1% Have Pool
100% Have Garage
This Home
$498,198
Median
$623,673

This home is -20.1% below the subdivision median.

Tax Analysis

The estimated annual property tax is $9,929 across all districts. With a homestead exemption claimed, that drops to $8,316 — saving $1,613 per year. That's $693 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%$5,415
Round RockCity0.3720%$1,853
Williamson CountyCounty0.3694%$1,841
Austin Community Collegespecial0.1034%$515
Williamson County FM/RdCounty0.0443%$221
Upper Brushy Creek WCIDWater0.0170%$85
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.9931%$9,929

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $500,322 would pay approximately $3,123 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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