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

12105 GREY ROCK LN, AUSTIN, TX 78750

AUSTIN, 78750 — williamson County

3 bed2 bath1,404 sqftBuilt 1977

Property at a Glance

This home is estimated between $327,732 and $403,037, with a best estimate of $341,081. That places the property below the R3P5480G - Anderson Mill 12,16 - 20 - Partially in TCAD median of $387,608, in a neighborhood that declined 7.3% over the past year.

Estimated Value Range

$327,732 $403,037
Best Estimate
$341,081
WCAD Value
$388,456
High Confidence

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

Based on 5 comparable properties in R3P5480G - Anderson Mill 12,16 - 20 - Partially in TCAD, this home's estimated market value is between $327,732 and $403,037. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

12103 GREY ROCK LN, AUSTIN, TX 78750
0.01 mi 100% similar Same subdivision
3 bed 2 bath 1,480 sqft Built 1977
Raw Value $346,452
Adjusted Value $327,732

Adjusted -$18,720 for 76 sqft less living space. Net adjustment: -$18,720.

12107 GREY ROCK LN, AUSTIN, TX 78750
0.01 mi 100% similar Same subdivision
3 bed 2 bath 1,444 sqft Built 1977
Raw Value $350,934
Adjusted Value $341,081

Adjusted -$9,853 for 40 sqft less living space. Net adjustment: -$9,853.

12101 GREY ROCK LN, AUSTIN, TX 78750
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,323 sqft Built 1977
Raw Value $383,085
Adjusted Value $403,037

Adjusted +$19,952 for 81 sqft more living space. Net adjustment: +$19,952.

12109 GREY ROCK LN, AUSTIN, TX 78750
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,549 sqft Built 1977
Raw Value $397,131
Adjusted Value $361,414

Adjusted -$35,717 for 145 sqft less living space. Net adjustment: -$35,717.

12104 GREY ROCK LN, AUSTIN, TX 78750
0.03 mi 100% similar Same subdivision
3 bed 2 bath 1,505 sqft Built 1977
Raw Value $355,419
Adjusted Value $330,540

Adjusted -$24,879 for 101 sqft less living space. Net adjustment: -$24,879.

The Neighborhood

This home is in line with the R3P5480G - Anderson Mill 12,16 - 20 - Partially in TCAD median of $387,608. Note that values in this subdivision declined 7.3% over the past year.

R3P5480G - Anderson Mill 12,16 - 20 - Partially in TCAD

typical
834 Properties
$387,608 Median Value
-7.3% YoY Change
2% Have Pool
97% Have Garage
This Home
$388,456
Median
$387,608

This home is +0.2% above the subdivision median.

Tax Analysis

The estimated annual property tax is $8,063 across all districts. With a homestead exemption claimed, that drops to $6,334 — saving $1,729 per year. That's $528 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%$3,469
AustinCity0.5240%$2,036
Williamson CountyCounty0.3694%$1,435
Anderson Mill Limited Districtspecial0.1243%$483
Austin Community Collegespecial0.1034%$402
Williamson County FM/RdCounty0.0443%$172
Upper Brushy Creek WCIDWater0.0170%$66
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax2.0756%$8,063

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $341,081 would pay approximately $2,129 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