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3890 CR 123, ROUND ROCK, TX 78664

ROUND ROCK, 78664 — williamson County

3 bed2 bath1,696 sqftBuilt 1984

Property at a Glance

This home is estimated between $178,208 and $316,715, with a best estimate of $307,223. That places the property below the R002D78G - East Round Rock Williamson Co Abstracts lt 20 Acs median of $594,322, in a neighborhood that declined 11.1% over the past year.

Estimated Value Range

$178,208 $316,715
Best Estimate
$307,223
WCAD Value
$399,839
Low Confidence

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

There are 5 comparable properties within range, but none are in R002D78G - East Round Rock Williamson Co Abstracts lt 20 Acs. The estimated range of $178,208 and $316,715 should be treated as a rough guide.

Comparable Properties (5)

3 bed 2 bath 1,525 sqft Built 1981
Raw Value $307,284
Adjusted Value $274,981

Adjusted +$56,231 for 171 sqft more living space and +$11,519 for being newer and -$100,053 for no garage. Net adjustment: -$32,303.

3 bed 2 bath 1,314 sqft Built 1982
Raw Value $273,981
Adjusted Value $307,223

Adjusted +$125,616 for 382 sqft more living space and +$7,679 for being newer and -$100,053 for no garage. Net adjustment: +$33,242.

3 bed 2 bath 1,260 sqft Built 1984
Raw Value $273,395
Adjusted Value $316,715

Adjusted +$143,373 for 436 sqft more living space and -$100,053 for no garage. Net adjustment: +$43,320.

3 bed 2 bath 1,285 sqft Built 1981
Raw Value $265,040
Adjusted Value $311,658

Adjusted +$135,152 for 411 sqft more living space and +$11,519 for being newer and -$100,053 for no garage. Net adjustment: +$46,618.

3 bed 2 bath 1,526 sqft Built 2002
Raw Value $291,474
Adjusted Value $178,208

Adjusted +$55,902 for 170 sqft more living space and -$69,115 for being older and -$100,053 for no garage. Net adjustment: -$113,266.

The Neighborhood

This home is valued 32.7% below the R002D78G - East Round Rock Williamson Co Abstracts lt 20 Acs median of $594,322. That positions it competitively for buyers comparing within the neighborhood. Note that values in this subdivision declined 11.1% over the past year.

R002D78G - East Round Rock Williamson Co Abstracts lt 20 Acs

below average
82 Properties
$594,322 Median Value
-11.1% YoY Change
1% Have Pool
43% Have Garage
This Home
$399,839
Median
$594,322

This home is -32.7% below the subdivision median.

Tax Analysis

The estimated annual property tax is $6,106 across all districts. With a homestead exemption claimed, that drops to $4,782 — saving $1,324 per year. That's $399 per month a buyer should budget. The assessed value increased -2.2% vs the subdivision average of -11.1%. This above-average increase gives a protest opportunity score of 45 out of 100 — it may be worth challenging the appraisal.

Tax Districts

DistrictTypeRateAnnual Amount
Round Rock ISDSchool0.8931%$3,571
Williamson CountyCounty0.3694%$1,477
Austin Community Collegespecial0.1034%$413
Williamson County ESD #9 - Round RockESD0.0999%$399
Williamson County FM/RdCounty0.0443%$177
Upper Brushy Creek WCIDWater0.0170%$68
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.5272%$6,106
45 / 100

Moderate opportunity to protest.

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $307,223 would pay approximately $1,918 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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