Skip to content
Skip to content
TopHapOpen in map
Single Family ResidenceResidential
$400,793$225 / ft²
TopHap EstimateOur estimate of what this home would sell for today, based on nearby sales, the home's size and features, and local price trends. It is a starting point, not an appraisal.· confidence 84How well the pricing models agreed with each other on this home. Higher means the estimate rests on stronger, more consistent data.· as of Jul 14, 2026

8400 HILLROCK DR

ROUND ROCK, TX 78681
3 / 1
Baths
1,780 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.
2008
Year BuiltThe year the home was originally built, according to county records.
2
StoriesHow many floors the home has above ground.
1
ParkingThe number of parking spaces on the property, including the garage.

Valuation

$401K
$338K low$463K high
Est. Owner EquityRoughly how much of the home's value the owner would keep after paying off known loans. It is our estimate minus the loans still owed.$400,793
Est. Lendable EquityThe part of the owner's equity a lender would typically let them borrow against — about 80% of their equity.$320,634

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$8,187 (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.$436,856 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$95,000
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$341,856
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$436,856
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$436,856

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Single Family Residence
CountyWilliamson
Effective Year BuiltAn adjusted build year that accounts for condition and major remodels. A big renovation can make a home count as newer than it is.2009
Lot (acres)The size of the land the home sits on, from county records.0.15
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.Patio · 125 ft²Porch · 72 ft²

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

E
Brushy Creek Elementary SchoolA
Elementary · Grades PK–5 · 0.5 mi
M
Cedar Valley Middle SchoolA+
Middle · Grades 6–8 · 1.2 mi
H
McNeil High SchoolA-
High · Grades 9–12 · 4.1 mi

District: Round Rock Independent School District

Neighborhood · ZIP 78681These 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.44
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.86
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.20

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.98%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.38%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.4.9%
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.72,545
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.3,224 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$126,547
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$146,868
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.No

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

8400 Hillrock Dr 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.

  • Worth less than 85% of homes in Cat Hollow
  • Costs more per square foot than 71% of homes in Williamson County
  • Smaller than 77% of homes in Cat Hollow
  • Has a smaller lot than 82% of homes in Round Rock 78681
  • Among the newest homes in Cat Hollow

What homes are worth in Round Rock 78681

Each bar is how many homes fall in that price range. The marker is this home.

This home
$256K$1.1M

This home is worth more than 24% of homes in Round Rock 78681.

How it measures up in Round Rock 78681

The dot is this home. The mark in the middle is the typical home in Round Rock 78681.

Estimated value$400,793
CheaperTypical $498,013Pricier

Pricier than 24% of homes nearby

Price per ft²$225
CheaperTypical $219Pricier

Pricier than 60% of homes nearby

Living area1,780 ft²
SmallerTypical 2,315 ft²Bigger

Bigger than 24% of homes nearby

Lot size0.16 ac
SmallerTypical 0.2 acBigger

Bigger than 18% of homes nearby

Year built2008
OlderTypical 1998Newer

Newer than 83% of homes nearby

How 8400 Hillrock Dr ranks against every home in each area.
MeasureThis homeCat HollowRound Rock 78681Williamson County
Estimated valuepricier than$400,79315% of homes24% of homes47% of homes
Price per ft²pricier than$22564% of homes60% of homes71% of homes
Living areabigger than1,780 ft²23% of homes24% of homes33% of homes
Lot sizebigger than0.16 ac29% of homes18% of homes22% of homes
Year builtnewer than2008almost all homes83% of homes54% of homes

About 8400 Hillrock Dr

How much is 8400 Hillrock Dr, Round Rock, TX worth?

The TopHap Estimate for 8400 Hillrock Dr, Round Rock, TX is $400,793 as of Jul 14, 2026. The likely range is $338,479 to $463,107. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 8400 Hillrock Dr, Round Rock, TX last sell?

8400 Hillrock Dr, Round Rock, TX last sold on Dec 2, 2014, according to the county's recorded deed.

How big is 8400 Hillrock Dr, Round Rock, TX?

8400 Hillrock Dr, Round Rock, TX has 3 bathrooms, 1,780 square feet of living space and a 0.15-acre lot.

When was 8400 Hillrock Dr, Round Rock, TX built?

8400 Hillrock Dr, Round Rock, TX was built in 2008, making it 18 years old. The building has 2 stories.

What schools serve 8400 Hillrock Dr, Round Rock, TX?

8400 Hillrock Dr, Round Rock, TX is assigned to Brushy Creek Elementary School (elementary), rated A; Cedar Valley Middle School (middle), rated A+; McNeil High School (high), rated A-. All sit in Round Rock Independent School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 8400 Hillrock Dr, Round Rock, TX compare to other homes in Round Rock 78681?

Among the 18,081 homes in Round Rock 78681, it is worth more than 24% of them ($400,793 against a typical $498,013), its price per square foot is higher than 60% of them ($225 against a typical $219), it is bigger than 24% of them (1,780 ft² against a typical 2,315 ft²), its lot is bigger than 18% of them (0.16 ac against a typical 0.2 ac) and it is newer than 83% of them (2008 against a typical 1998). Measured against all of Williamson County, it is worth more than 47% of homes there. These shares are recounted nightly from the full county assessor record for each area, not from active listings.

What are the property taxes on 8400 Hillrock Dr, Round Rock, TX?

The 2025 property tax bill for 8400 Hillrock Dr, Round Rock, TX was $8,187. The county assessed it at $436,856.

More homes on Hillrock Dr

Closest homes

More homes in Round Rock 78681

Assigned schools

Explore the area

See this home in context

Open 8400 Hillrock Dr on TopHap’s interactive map to compare it against every sale nearby, overlay school zones and flood risk, and run a CMA.

Open in map
A flyover of TopHap's photorealistic 3D map, with recorded sale prices pinned to homes
Search any address, city, zip, or county…3D$1.9M$6.25MOpen in map