Beta Williamson County, TX only — data and coverage are limited during early access.

3100 CARNOUSTY ST, ROUND ROCK, TX 78664

ROUND ROCK, 78664 — williamson County

4 bed4 bath2,193 sqftBuilt 2001

Property at a Glance

This home is estimated between $632,941 and $850,402, with a best estimate of $740,548. That places the property below the R549699C - Forest Creek Sec 14,20,21,26-30,33,34 median of $910,927, in a neighborhood that declined 3.1% over the past year.

Estimated Value Range

$632,941 $850,402
Best Estimate
$740,548
WCAD Value
$959,110
High Confidence

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

Based on 5 comparable properties in R549699C - Forest Creek Sec 14,20,21,26-30,33,34, this home's estimated market value is between $632,941 and $850,402. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3120 CARNOUSTY ST, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
4 bed 2 bath 2,162 sqft Built 2003
Raw Value $726,778
Adjusted Value $740,548

Adjusted +$10,845 for 31 sqft more living space and +$2,925 for being newer. Net adjustment: +$13,770.

3605 CARNOUSTY CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
5 bed 4 bath 2,526 sqft Built 2001
Raw Value $905,900
Adjusted Value $789,400

Adjusted -$116,500 for 333 sqft less living space. Net adjustment: -$116,500.

3104 CARNOUSTY ST, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
5 bed 4 bath 2,515 sqft Built 2001
Raw Value $841,337
Adjusted Value $728,685

Adjusted -$112,652 for 322 sqft less living space. Net adjustment: -$112,652.

3114 CARNOUSTY ST, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
4 bed 3 bath 2,899 sqft Built 2005
Raw Value $874,085
Adjusted Value $632,941

Adjusted -$246,994 for 706 sqft less living space and +$5,850 for being newer. Net adjustment: -$241,144.

3118 CARNOUSTY ST, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
5 bed 4 bath 2,438 sqft Built 2014
Raw Value $917,104
Adjusted Value $850,402

Adjusted -$85,713 for 245 sqft less living space and +$19,011 for being newer. Net adjustment: -$66,702.

The Neighborhood

This home is valued 5.3% above the R549699C - Forest Creek Sec 14,20,21,26-30,33,34 median of $910,927. With 271 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 3.1% over the past year.

R549699C - Forest Creek Sec 14,20,21,26-30,33,34

typical
271 Properties
$910,927 Median Value
-3.1% YoY Change
1% Have Pool
99% Have Garage
This Home
$959,110
Median
$910,927

This home is +5.3% above the subdivision median.

Tax Analysis

The estimated annual property tax is $17,257 across all districts. With a homestead exemption claimed, that drops to $15,830 — saving $1,427 per year. That's $1,319 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%$8,566
Round RockCity0.3720%$3,568
Williamson CountyCounty0.3694%$3,543
Austin Community Collegespecial0.1034%$992
Williamson County FM/RdCounty0.0443%$425
Upper Brushy Creek WCIDWater0.0170%$163
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$17,257

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $740,548 would pay approximately $4,622 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.

View full property details