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3921 SAPPHIRE LOOP, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

3 bed2 bath2,300 sqftBuilt 2007

Property at a Glance

This home is estimated between $425,152 and $770,086, with a best estimate of $636,362. 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

$425,152 $770,086
Best Estimate
$636,362
WCAD Value
$479,698
Medium Confidence

Based on 5 comparable properties(4 in the same subdivision)

Based on 5 comparable properties (4 in the same subdivision, 1 nearby), the estimated range is $425,152 and $770,086. More comparables in the same subdivision would strengthen this estimate.

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 $533,430

Adjusted -$67,730 for 221 sqft less living space and -$1,997 for being older. Net adjustment: -$69,727.

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 $659,985

Adjusted +$29,114 for 95 sqft more living space and -$7,990 for being older. Net adjustment: +$21,124.

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 $770,086

Adjusted +$91,021 for 297 sqft more living space and -$7,990 for being older. Net adjustment: +$83,031.

3 bed 2 bath 2,195 sqft Built 2004
Raw Value $598,191
Adjusted Value $636,362

Adjusted +$32,179 for 105 sqft more living space and +$5,992 for being newer. Net adjustment: +$38,171.

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 $425,152

Adjusted -$66,504 for 217 sqft less living space. Net adjustment: -$66,504.

The Neighborhood

This home is valued 23.1% 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
$479,698
Median
$623,673

This home is -23.1% below the subdivision median.

Tax Analysis

The estimated annual property tax is $9,561 across all districts. With a homestead exemption claimed, that drops to $7,950 — saving $1,611 per year. That's $663 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%$5,214
Round RockCity0.3720%$1,784
Williamson CountyCounty0.3694%$1,772
Austin Community Collegespecial0.1034%$496
Williamson County FM/RdCounty0.0443%$213
Upper Brushy Creek WCIDWater0.0170%$82
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.9931%$9,561

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $636,362 would pay approximately $3,972 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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