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901 MAMMOTH CT, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

3 bed2 bath730 sqftBuilt 2000

Property at a Glance

This home is estimated between $121,465 and $399,062, with a best estimate of $135,435. That places the property below the R107503F - PRESERVE AT STONE OAK - PH 3 & 4 median of $368,194, in a neighborhood that declined 10.9% over the past year.

Estimated Value Range

$121,465 $399,062
Best Estimate
$135,435
WCAD Value
$295,858
Low Confidence

Based on 5 comparable properties(0 in the same subdivision)

There are 5 comparable properties within range, but none are in R107503F - PRESERVE AT STONE OAK - PH 3 & 4. The estimated range of $121,465 and $399,062 should be treated as a rough guide.

Comparable Properties (5)

3 bed 2 bath 977 sqft Built 1987
Raw Value $396,067
Adjusted Value $327,574

Adjusted -$50,283 for 247 sqft less living space and -$18,210 for being older. Net adjustment: -$68,493.

3 bed 2 bath 1,020 sqft Built 1977
Raw Value $212,719
Adjusted Value $121,465

Adjusted -$59,036 for 290 sqft less living space and -$32,218 for being older. Net adjustment: -$91,254.

3 bed 2 bath 1,057 sqft Built 1977
Raw Value $234,221
Adjusted Value $135,435

Adjusted -$66,568 for 327 sqft less living space and -$32,218 for being older. Net adjustment: -$98,786.

4 bed 3 bath 991 sqft Built 1992
Raw Value $463,401
Adjusted Value $399,062

Adjusted -$53,133 for 261 sqft less living space and -$11,206 for being older. Net adjustment: -$64,339.

3 bed 2 bath 1,110 sqft Built 1977
Raw Value $231,850
Adjusted Value $122,274

Adjusted -$77,358 for 380 sqft less living space and -$32,218 for being older. Net adjustment: -$109,576.

The Neighborhood

This home is valued 19.6% below the R107503F - PRESERVE AT STONE OAK - PH 3 & 4 median of $368,194. That positions it competitively for buyers comparing within the neighborhood. Note that values in this subdivision declined 10.9% over the past year.

R107503F - PRESERVE AT STONE OAK - PH 3 & 4

below average
1,045 Properties
$368,194 Median Value
-10.9% YoY Change
1% Have Pool
99% Have Garage
This Home
$295,858
Median
$368,194

This home is -19.6% below the subdivision median.

Tax Analysis

The estimated annual property tax is $5,323 across all districts. With a homestead exemption claimed, that drops to $4,018 — saving $1,305 per year. That's $335 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%$2,642
Round RockCity0.3720%$1,101
Williamson CountyCounty0.3694%$1,093
Austin Community Collegespecial0.1034%$306
Williamson County FM/RdCounty0.0443%$131
Upper Brushy Creek WCIDWater0.0170%$50
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$5,323

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $135,435 would pay approximately $845 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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