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3809 SPYGLASS CV, ROUND ROCK, TX 78664

ROUND ROCK, 78664 — williamson County

4 bed3 bath2,146 sqftBuilt 2005

Property at a Glance

This home is estimated between $251,716 and $623,145, with a best estimate of $439,826. That places the property below the R550600D - Forest Creek Sec 15,16,19,31 median of $514,276, in a neighborhood that declined 8.7% over the past year.

Estimated Value Range

$251,716 $623,145
Best Estimate
$439,826
WCAD Value
$595,480
High Confidence

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

Based on 5 comparable properties in R550600D - Forest Creek Sec 15,16,19,31, this home's estimated market value is between $251,716 and $623,145. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3802 SPYGLASS CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
4 bed 2 bath 1,634 sqft Built 2004
Raw Value $474,694
Adjusted Value $623,145

Adjusted +$146,486 for 512 sqft more living space and +$1,965 for being newer. Net adjustment: +$148,451.

3800 SPYGLASS CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,180 sqft Built 2004
Raw Value $447,589
Adjusted Value $439,826

Adjusted -$9,728 for 34 sqft less living space and +$1,965 for being newer. Net adjustment: -$7,763.

3804 SPYGLASS CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
4 bed 2,013 sqft Built 2004
Raw Value $525,320
Adjusted Value $565,337

Adjusted +$38,052 for 133 sqft more living space and +$1,965 for being newer. Net adjustment: +$40,017.

3801 SPYGLASS CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
4 bed 3 bath 3,011 sqft Built 2004
Raw Value $497,233
Adjusted Value $251,716

Adjusted -$247,482 for 865 sqft less living space and +$1,965 for being newer. Net adjustment: -$245,517.

3803 SPYGLASS CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,527 sqft Built 2003
Raw Value $491,158
Adjusted Value $386,081

Adjusted -$109,007 for 381 sqft less living space and +$3,930 for being newer. Net adjustment: -$105,077.

The Neighborhood

This home is valued 15.8% above the R550600D - Forest Creek Sec 15,16,19,31 median of $514,276. With 274 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 8.7% over the past year.

R550600D - Forest Creek Sec 15,16,19,31

above average
274 Properties
$514,276 Median Value
-8.7% YoY Change
0% Have Pool
99% Have Garage
This Home
$595,480
Median
$514,276

This home is +15.8% above the subdivision median.

Tax Analysis

The estimated annual property tax is $10,714 across all districts. With a homestead exemption claimed, that drops to $9,354 — saving $1,360 per year. That's $780 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
Round Rock ISDSchool0.8931%$5,318
Round RockCity0.3720%$2,215
Williamson CountyCounty0.3694%$2,200
Austin Community Collegespecial0.1034%$616
Williamson County FM/RdCounty0.0443%$264
Upper Brushy Creek WCIDWater0.0170%$101
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$10,714

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $439,826 would pay approximately $2,745 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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