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903 MAMMOTH CT, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

4 bed2 bath1,105 sqftBuilt 2000

Property at a Glance

This home is estimated between $361,832 and $435,098, with a best estimate of $395,393. That places the property above 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

$361,832 $435,098
Best Estimate
$395,393
WCAD Value
$375,280
High Confidence

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

Based on 5 comparable properties in R107503F - PRESERVE AT STONE OAK - PH 3 & 4, this home's estimated market value is between $361,832 and $435,098. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

904 MAMMOTH CT, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 920 sqft Built 2000
Raw Value $397,437
Adjusted Value $435,098

Adjusted +$37,661 for 185 sqft more living space. Net adjustment: +$37,661.

905 MAMMOTH CT, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 966 sqft Built 2000
Raw Value $367,096
Adjusted Value $395,393

Adjusted +$28,297 for 139 sqft more living space. Net adjustment: +$28,297.

908 MAMMOTH CT, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 3 bath 966 sqft Built 2000
Raw Value $370,309
Adjusted Value $398,606

Adjusted +$28,297 for 139 sqft more living space. Net adjustment: +$28,297.

907 MAMMOTH CT, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 2 bath 1,105 sqft Built 2000
Raw Value $361,832
Adjusted Value $361,832

This comparable closely matches the subject property's features.

911 MAMMOTH CT, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 2 bath 1,105 sqft Built 2000
Raw Value $363,033
Adjusted Value $363,033

This comparable closely matches the subject property's features.

The Neighborhood

This home is valued 1.9% above the R107503F - PRESERVE AT STONE OAK - PH 3 & 4 median of $368,194. With 1,045 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 10.9% over the past year.

R107503F - PRESERVE AT STONE OAK - PH 3 & 4

typical
1,045 Properties
$368,194 Median Value
-10.9% YoY Change
1% Have Pool
99% Have Garage
This Home
$375,280
Median
$368,194

This home is +1.9% above the subdivision median.

Tax Analysis

The estimated annual property tax is $6,752 across all districts. With a homestead exemption claimed, that drops to $5,433 — saving $1,319 per year. That's $453 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%$3,352
Round RockCity0.3720%$1,396
Williamson CountyCounty0.3694%$1,386
Austin Community Collegespecial0.1034%$388
Williamson County FM/RdCounty0.0443%$166
Upper Brushy Creek WCIDWater0.0170%$64
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$6,752

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $395,393 would pay approximately $2,468 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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