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509 MAIN AVE E, ROUND ROCK, TX 78664

ROUND ROCK, 78664 — williamson County

3 bed2 bath2,339 sqftBuilt 1930

Property at a Glance

This home is estimated between $423,855 and $812,078, with a best estimate of $792,273. That places the property above the R703T14G - Round Rock Historical median of $404,269, in a neighborhood that appreciated 33.1% over the past year.

Estimated Value Range

$423,855 $812,078
Best Estimate
$792,273
WCAD Value
$740,145
High Confidence

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

Based on 5 comparable properties in R703T14G - Round Rock Historical, this home's estimated market value is between $423,855 and $812,078. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

702 MAIN AVE E, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,818 sqft Built 1920
Raw Value $706,832
Adjusted Value $812,078

Adjusted +$164,155 for 521 sqft more living space and -$58,909 for being older. Net adjustment: +$105,246.

702 MAIN AVE E, ROUND ROCK, TX 78664
0.00 mi 98% similar Same subdivision
3 bed 2 bath 1,818 sqft Built 1920
Raw Value $687,027
Adjusted Value $792,273

Adjusted +$164,155 for 521 sqft more living space and -$58,909 for being older. Net adjustment: +$105,246.

808 MAIN AVE E, ROUND ROCK, TX 78664
0.00 mi 95% similar Same subdivision
3 bed 2 bath 1,510 sqft Built 1930
Raw Value $658,171
Adjusted Value $811,844

Adjusted +$261,199 for 829 sqft more living space and -$107,526 for no garage. Net adjustment: +$153,673.

507 MAIN AVE E, ROUND ROCK, TX 78664
0.00 mi 90% similar Same subdivision
4 bed 3 bath 2,735 sqft Built 1920
Raw Value $607,535
Adjusted Value $423,855

Adjusted -$124,771 for 396 sqft less living space and -$58,909 for being older. Net adjustment: -$183,680.

701 E MAIN ST, ROUND ROCK, TX 78664
0.00 mi 89% similar Same subdivision
2 bed 1 bath 1,542 sqft Built 1930
Raw Value $404,269
Adjusted Value $655,386

Adjusted +$251,117 for 797 sqft more living space. Net adjustment: +$251,117.

The Neighborhood

This home is valued 83.1% above the R703T14G - Round Rock Historical median of $404,269. With 59 homes in the subdivision, the property sits in the upper tier. The neighborhood appreciated 33.1% over the past year.

R703T14G - Round Rock Historical

outlier high
59 Properties
$404,269 Median Value
+33.1% YoY Change
9% Have Pool
14% Have Garage
This Home
$740,145
Median
$404,269

This home is +83.1% above the subdivision median.

Tax Analysis

The estimated annual property tax is $13,317 across all districts. With a homestead exemption claimed, that drops to $11,930 — saving $1,387 per year. That's $994 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%$6,610
Round RockCity0.3720%$2,753
Williamson CountyCounty0.3694%$2,734
Austin Community Collegespecial0.1034%$765
Williamson County FM/RdCounty0.0443%$328
Upper Brushy Creek WCIDWater0.0170%$126
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$13,317

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $792,273 would pay approximately $4,945 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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