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4018 MASON CV, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

3 bed2 bath2,522 sqftBuilt 2015

Property at a Glance

This home is estimated between $496,198 and $640,647, with a best estimate of $527,079. That places the property above the G799514C - MAYFIELD RANCH median of $523,371, in a neighborhood that declined 9.3% over the past year.

Estimated Value Range

$496,198 $640,647
Best Estimate
$527,079
WCAD Value
$493,284
Medium Confidence

Based on 5 comparable properties(4 in the same subdivision)

Based on 5 comparable properties (4 in the same subdivision, 1 nearby), the estimated range is $496,198 and $640,647. More comparables in the same subdivision would strengthen this estimate.

Comparable Properties (5)

4025 MASON CV, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,241 sqft Built 2015
Raw Value $477,050
Adjusted Value $539,340

Adjusted +$62,290 for 281 sqft more living space. Net adjustment: +$62,290.

4009 MASON CV, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
3 bed 1 bath 2,560 sqft Built 2014
Raw Value $502,796
Adjusted Value $496,198

Adjusted -$8,424 for 38 sqft less living space and +$1,826 for being newer. Net adjustment: -$6,598.

4030 MASON CV, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 3 bath 2,311 sqft Built 2016
Raw Value $482,132
Adjusted Value $527,079

Adjusted +$46,773 for 211 sqft more living space and -$1,826 for being older. Net adjustment: +$44,947.

4029 MASON CV, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 3 bath 2,662 sqft Built 2014
Raw Value $542,966
Adjusted Value $513,758

Adjusted -$31,034 for 140 sqft less living space and +$1,826 for being newer. Net adjustment: -$29,208.

3 bed 2 bath 2,530 sqft Built 2004
Raw Value $622,333
Adjusted Value $640,647

Adjusted -$1,773 for 8 sqft less living space and +$20,087 for being newer. Net adjustment: +$18,314.

The Neighborhood

This home is valued 5.7% 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
$493,284
Median
$523,371

This home is -5.7% below the subdivision median.

Tax Analysis

The estimated annual property tax is $10,193 across all districts. With a homestead exemption claimed, that drops to $8,631 — saving $1,562 per year. That's $719 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%$5,182
Highlands at Mayfield Ranch MUDMUD0.4850%$2,392
Williamson CountyCounty0.3694%$1,822
Williamson County ESD #9 - Round RockESD0.0999%$493
Williamson County FM/RdCounty0.0443%$219
Upper Brushy Creek WCIDWater0.0170%$84
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax2.0663%$10,193

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $527,079 would pay approximately $3,290 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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