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12013 GREY ROCK LN, AUSTIN, TX 78750

AUSTIN, 78750 — williamson County

4 bed2 bath1,617 sqftBuilt 1977

Property at a Glance

This home is estimated between $342,445 and $455,504, with a best estimate of $404,898. That places the property above 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

$342,445 $455,504
Best Estimate
$404,898
WCAD Value
$429,817
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 $342,445 and $455,504. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

12015 GREY ROCK LN, AUSTIN, TX 78750
0.01 mi 100% similar Same subdivision
3 bed 2 bath 1,830 sqft Built 1977
Raw Value $394,912
Adjusted Value $342,445

Adjusted -$52,467 for 213 sqft less living space. Net adjustment: -$52,467.

12011 GREY ROCK LN, AUSTIN, TX 78750
0.01 mi 100% similar Same subdivision
3 bed 2 bath 1,444 sqft Built 1977
Raw Value $370,315
Adjusted Value $412,929

Adjusted +$42,614 for 173 sqft more living space. Net adjustment: +$42,614.

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 $455,504

Adjusted +$72,419 for 294 sqft more living space. Net adjustment: +$72,419.

12009 GREY ROCK LN, AUSTIN, TX 78750
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,323 sqft Built 1977
Raw Value $332,479
Adjusted Value $404,898

Adjusted +$72,419 for 294 sqft more living space. Net adjustment: +$72,419.

12004 GREY ROCK LN, AUSTIN, TX 78750
0.03 mi 100% similar Same subdivision
3 bed 2 bath 1,410 sqft Built 1977
Raw Value $344,616
Adjusted Value $395,605

Adjusted +$50,989 for 207 sqft more living space. Net adjustment: +$50,989.

The Neighborhood

This home is valued 10.9% above the R3P5480G - Anderson Mill 12,16 - 20 - Partially in TCAD median of $387,608. With 834 homes in the subdivision, the property sits in the upper tier. 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
$429,817
Median
$387,608

This home is +10.9% above the subdivision median.

Tax Analysis

The estimated annual property tax is $8,921 across all districts. With a homestead exemption claimed, that drops to $7,141 — saving $1,780 per year. That's $595 per month a buyer should budget. The assessed value increased +11.9% vs the subdivision average of -7.3%. This above-average increase gives a protest opportunity score of 75 out of 100 — it may be worth challenging the appraisal.

Tax Districts

DistrictTypeRateAnnual Amount
Round Rock ISDSchool0.8931%$3,839
AustinCity0.5240%$2,252
Williamson CountyCounty0.3694%$1,588
Anderson Mill Limited Districtspecial0.1243%$534
Austin Community Collegespecial0.1034%$444
Williamson County FM/RdCounty0.0443%$191
Upper Brushy Creek WCIDWater0.0170%$73
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax2.0756%$8,921
75 / 100

There may be a strong case to protest this appraisal.

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $404,898 would pay approximately $2,527 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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