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4521 POST LOOP, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

4 bed3 bath2,256 sqftBuilt 2021

Property at a Glance

This home is estimated between $489,923 and $654,379, with a best estimate of $491,893. That places the property below the G799514C - MAYFIELD RANCH median of $523,371, in a neighborhood that declined 9.3% over the past year.

Estimated Value Range

$489,923 $654,379
Best Estimate
$491,893
WCAD Value
$487,592
High Confidence

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

Based on 5 comparable properties in G799514C - MAYFIELD RANCH, this home's estimated market value is between $489,923 and $654,379. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

4582 POST LOOP, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 3 bath 2,023 sqft Built 2021
Raw Value $602,729
Adjusted Value $654,379

Adjusted +$51,650 for 233 sqft more living space. Net adjustment: +$51,650.

4609 POST LN, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,112 sqft Built 2020
Raw Value $458,146
Adjusted Value $491,893

Adjusted +$31,921 for 144 sqft more living space and +$1,826 for being newer. Net adjustment: +$33,747.

3832 ASHBURY RD, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 3 bath 2,144 sqft Built 2016
Raw Value $582,790
Adjusted Value $616,747

Adjusted +$24,827 for 112 sqft more living space and +$9,130 for being newer. Net adjustment: +$33,957.

3625 ASHBURY RD, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,273 sqft Built 2016
Raw Value $485,139
Adjusted Value $490,501

Adjusted -$3,768 for 17 sqft less living space and +$9,130 for being newer. Net adjustment: +$5,362.

3712 ASHBURY RD, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,271 sqft Built 2015
Raw Value $482,291
Adjusted Value $489,923

Adjusted -$3,325 for 15 sqft less living space and +$10,957 for being newer. Net adjustment: +$7,632.

The Neighborhood

This home is valued 6.8% below the G799514C - MAYFIELD RANCH median of $523,371. That positions it competitively for buyers comparing within the neighborhood. Note that values in this subdivision declined 9.3% over the past year.

G799514C - MAYFIELD RANCH

typical
1,093 Properties
$523,371 Median Value
-9.3% YoY Change
1% Have Pool
100% Have Garage
This Home
$487,592
Median
$523,371

This home is -6.8% below the subdivision median.

Tax Analysis

The estimated annual property tax is $10,075 across all districts. With a homestead exemption claimed, that drops to $8,514 — saving $1,561 per year. That's $710 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
Georgetown ISDSchool1.0506%$5,123
Highlands at Mayfield Ranch MUDMUD0.4850%$2,365
Williamson CountyCounty0.3694%$1,801
Williamson County ESD #9 - Round RockESD0.0999%$487
Williamson County FM/RdCounty0.0443%$216
Upper Brushy Creek WCIDWater0.0170%$83
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax2.0663%$10,075

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $491,893 would pay approximately $3,070 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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