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3840 SAPPHIRE LOOP, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

3 bed2 bath2,821 sqftBuilt 2007

Property at a Glance

This home is estimated between $527,336 and $693,101, with a best estimate of $584,822. 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

$527,336 $693,101
Best Estimate
$584,822
WCAD Value
$611,415
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 $527,336 and $693,101. 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 $693,101

Adjusted +$91,941 for 300 sqft more living space and -$1,997 for being older. Net adjustment: +$89,944.

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 $584,822

Adjusted +$93,166 for 304 sqft more living space. Net adjustment: +$93,166.

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 $589,651

Adjusted +$99,602 for 325 sqft more living space and -$7,990 for being older. Net adjustment: +$91,612.

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 $548,381

Adjusted -$12,259 for 40 sqft less living space and -$1,997 for being older. Net adjustment: -$14,256.

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 $527,336

Adjusted -$118,603 for 387 sqft less living space and -$1,997 for being older. Net adjustment: -$120,600.

The Neighborhood

This home is valued 2.0% 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
$611,415
Median
$623,673

This home is -2.0% below the subdivision median.

Tax Analysis

The estimated annual property tax is $12,186 across all districts. With a homestead exemption claimed, that drops to $10,551 — saving $1,635 per year. That's $879 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%$6,645
Round RockCity0.3720%$2,274
Williamson CountyCounty0.3694%$2,259
Austin Community Collegespecial0.1034%$632
Williamson County FM/RdCounty0.0443%$271
Upper Brushy Creek WCIDWater0.0170%$104
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.9931%$12,186

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $584,822 would pay approximately $3,650 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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