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Duplex (2 Units, Any Combination)Residential

509/511 SIERRA CV

ROUND ROCK, TX 78664
4
Baths
1,815 ft²
Living AreaTotal finished area of the structures, from county records. Some counties include shared space like hallways or a building gym, so it may not match a listing.
0.16 ac
Lot SizeThe size of the land the home sits on, from county records.
1984
Year BuiltThe year the home was originally built, according to county records.
1
StoriesHow many floors the home has above ground.
2
ParkingThe number of parking spaces on the property, including the garage.

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$7,044 (2025)
Assessed ValueThe value the county assigns to this home to calculate property tax. It is often lower than what the home would sell for.$367,165 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$77,000
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$290,165
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$367,165
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$367,165

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Duplex (2 Units, Any Combination)
CountyWilliamson
FoundationWhat the home is built on, such as a concrete slab, a crawl space, or a basement.Mat/Raft Foundation (Slab)
HeatingThe type of heating system in the home.Central
CoolingThe type of cooling or air conditioning in the home.Central
PoolWhether the property has a pool, and what kind, such as in-ground.No
FeaturesExtra features found in county records. Records are not complete everywhere, so a missing feature does not always mean the home lacks it.Porch · 264 ft²

Transaction History(5)

Sales and refinances filed with the county for this home. Not every transfer is a normal sale, so check the type before comparing prices.

Foreclosure Filings(2)

Assigned SchoolsThe public schools this address is zoned for. Boundaries change, so confirm with the district before you count on it.

M
Hernandez Middle SchoolC+
Middle · Grades 6–8 · 0.4 mi
H
Stony Point High SchoolC+
High · Grades 9–12 · 0.7 mi
E
Union Hill Elementary SchoolC-
Elementary · Grades PK–5 · 1.8 mi

District: Round Rock Independent School District

Neighborhood · ZIP 78664These are comparison scores, not percentages. 100 equals the national average, so 150 means about 50% above average.

CrimeLocal crime compared with the rest of the country, where 100 is average. It reflects things like population density, income, and how crime gets reported.87
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.87
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.13

Index scale: 100 = US average (tick). Lower is better.

Homes occupiedThe share of homes here that someone lives in. The rest sit empty, including vacation and for-sale homes.96%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.24%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.8.6%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.4%
PopulationHow many people live in this area.72,016
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.4,336 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$88,209
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$105,122
Average tempThe average temperature here across a full year.67°F
Annual precipHow much rain and melted snow falls here in a typical year.35 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.60%

Ownership

OccupancyWhether the owner appears to live here or somewhere else. It is inferred from the mailing address on record.Absentee owner
Company ownedWhether the owner is a company or trust rather than a person.Yes

Data by ATTOM. Valuations are automated estimates, not appraisals. Photos from Google Street View and may not depict the current property state.

How this home compares

509/511 Sierra Cv measured against every home in its neighborhood, its ZIP code and its county, using county assessor records refreshed nightly. A home can stand out in one of those areas and look ordinary in another, because each one holds a different mix of homes.

  • Smaller than 65% of homes in Williamson County
  • Has a smaller lot than 75% of homes in Williamson County
  • Older than 87% of homes in Williamson County

How it measures up in Round Rock 78664

The dot is this home. The mark in the middle is the typical home in Round Rock 78664.

Living area1,815 ft²
SmallerTypical 1,768 ft²Bigger

Bigger than 53% of homes nearby

Lot size0.16 ac
SmallerTypical 0.18 acBigger

Bigger than 35% of homes nearby

Year built1984
OlderTypical 1998Newer

Newer than 24% of homes nearby

How 509/511 Sierra Cv ranks against every home in each area.
MeasureThis homeRound Rock 78664Williamson County
Living areabigger than1,815 ft²53% of homes35% of homes
Lot sizebigger than0.16 ac35% of homes25% of homes
Year builtnewer than198424% of homes13% of homes

About 509/511 Sierra Cv

When did 509/511 Sierra Cv, Round Rock, TX last sell?

509/511 Sierra Cv, Round Rock, TX last sold on Aug 11, 2023, according to the county's recorded deed.

How big is 509/511 Sierra Cv, Round Rock, TX?

509/511 Sierra Cv, Round Rock, TX has 4 bathrooms and 1,815 square feet of living space.

When was 509/511 Sierra Cv, Round Rock, TX built?

509/511 Sierra Cv, Round Rock, TX was built in 1984, making it 42 years old. The building has 1 story.

What schools serve 509/511 Sierra Cv, Round Rock, TX?

509/511 Sierra Cv, Round Rock, TX is assigned to Hernandez Middle School (middle), rated C+; Stony Point High School (high), rated C+; Union Hill Elementary School (elementary), rated C-. All sit in Round Rock Independent School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 509/511 Sierra Cv, Round Rock, TX compare to other homes in Round Rock 78664?

Among the 17,091 homes in Round Rock 78664, it is bigger than 53% of them (1,815 ft² against a typical 1,768 ft²), its lot is bigger than 35% of them (0.16 ac against a typical 0.18 ac) and it is newer than 24% of them (1984 against a typical 1998). These shares are recounted nightly from the full county assessor record for each area, not from active listings.

What are the property taxes on 509/511 Sierra Cv, Round Rock, TX?

The 2025 property tax bill for 509/511 Sierra Cv, Round Rock, TX was $7,044. The county assessed it at $367,165.

More homes on 509/511 Sierra Cv

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Assigned schools

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