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Single Family ResidenceResidential
$572,960$325 / 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 91How well the pricing models agreed with each other on this home. Higher means the estimate rests on stronger, more consistent data.· as of Sep 24, 2026

309 ALTA ST

BRENTWOOD, CA 94513
4
Beds
2.5
Baths
1,762 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.
2,842 ft²
Lot SizeThe size of the land the home sits on, from county records.
2016
Year BuiltThe year the home was originally built, according to county records.
2
StoriesHow many floors the home has above ground.
9
RoomsThe total room count in county records. Counties differ on which rooms they count, so compare it loosely.
2
ParkingThe number of parking spaces on the property, including the garage.

Valuation

$573K
$520K low$626K high

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$7,482 (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.$524,034 (2026)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$181,117
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$342,917
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$513,760

Climate Risk

Overall riskThe average of the five hazard scores below, on a 0 to 100 scale. Higher means greater projected risk over the coming decades.33
1
FloodProjected flooding risk from rivers, heavy rain, and storm surge, scored 0 to 100. Higher is riskier.
73
WildfireProjected wildfire risk, scored 0 to 100, based on how much land burns in a typical year. Higher is riskier.
45
HeatProjected heat risk, scored 0 to 100, based on how many extremely hot days a year are expected. Higher is riskier.
23
StormProjected risk from heavy rainstorms, scored 0 to 100, based on how often extreme rainfall is expected. Higher is riskier.
25
DroughtProjected water shortage risk, scored 0 to 100. Higher means more strain on the local water supply.

Scores 0–100; higher = greater projected risk.

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Single Family Residence
CountyCONTRA COSTA
Lot (acres)The size of the land the home sits on, from county records.0.07
CoolingThe type of cooling or air conditioning in the home.Central
GarageWhether the property has a garage, and details like whether it is attached to the home.Garage, Attached
PoolWhether the property has a pool, and what kind, such as in-ground.No

Transaction History(1)

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

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

E
Garin Elementary SchoolB+
Elementary · Grades KG–5 · 0.5 mi
M
Edna Hill Middle SchoolB
Middle · Grades 6–8 · 0.7 mi
H
Liberty High SchoolB
High · Grades 9–12 · 1.1 mi

District: Brentwood Union Elementary School District

Neighborhood · ZIP 94513These 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.48
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.83
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.368

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.26%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.6.8%
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.76,553
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.833 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$129,971
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$155,579
Average tempThe average temperature here across a full year.60°F
Annual precipHow much rain and melted snow falls here in a typical year.16 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.78%

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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

309 Alta St 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 87% of homes in Brentwood 94513
  • Costs less per square foot than 83% of homes in Contra Costa County
  • Smaller than 75% of homes in Brentwood 94513
  • Has a smaller lot than 97% of homes in Brentwood 94513
  • Newer than 97% of homes in Contra Costa County

What homes are worth in Brentwood 94513

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

This home
$417K$1.3M

This home is worth more than 13% of homes in Brentwood 94513.

How it measures up in Brentwood 94513

The dot is this home. The mark in the middle is the typical home in Brentwood 94513.

Estimated value$572,960
CheaperTypical $750,991Pricier

Pricier than 13% of homes nearby

Price per ft²$325
CheaperTypical $332Pricier

Pricier than 46% of homes nearby

Living area1,762 ft²
SmallerTypical 2,246 ft²Bigger

Bigger than 25% of homes nearby

Lot size2,842 ft²
SmallerTypical 0.16 acBigger

Bigger than 3% of homes nearby

Year built2016
OlderTypical 2002Newer

Newer than 90% of homes nearby

How 309 Alta St ranks against every home in each area.
MeasureThis homeBrentwood 94513Contra Costa County
Estimated valuepricier than$572,96013% of homes28% of homes
Price per ft²pricier than$32546% of homes17% of homes
Living areabigger than1,762 ft²25% of homes51% of homes
Lot sizebigger than2,842 ft²3% of homes15% of homes
Year builtnewer than201690% of homes97% of homes

About 309 Alta St

How much is 309 Alta St, Brentwood, CA worth?

The TopHap Estimate for 309 Alta St, Brentwood, CA is $572,960 as of Sep 24, 2026. The likely range is $520,413 to $625,507. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 309 Alta St, Brentwood, CA last sell?

309 Alta St, Brentwood, CA last sold on Jan 1, 1900, according to the county's recorded deed.

How big is 309 Alta St, Brentwood, CA?

309 Alta St, Brentwood, CA has 4 bedrooms, 2.5 bathrooms, 1,762 square feet of living space and a 0.07-acre lot.

When was 309 Alta St, Brentwood, CA built?

309 Alta St, Brentwood, CA was built in 2016, making it 10 years old. The building has 2 stories.

What schools serve 309 Alta St, Brentwood, CA?

309 Alta St, Brentwood, CA is assigned to Garin Elementary School (elementary), rated B+; Edna Hill Middle School (middle), rated B; Liberty High School (high), rated B. All sit in Brentwood Union Elementary School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 309 Alta St, Brentwood, CA compare to other homes in Brentwood 94513?

Among the 21,449 homes in Brentwood 94513, it is worth more than 13% of them ($572,960 against a typical $750,991), its price per square foot is higher than 46% of them ($325 against a typical $332), it is bigger than 25% of them (1,762 ft² against a typical 2,246 ft²), its lot is bigger than 3% of them (2,842 ft² against a typical 0.16 ac) and it is newer than 90% of them (2016 against a typical 2002). Measured against all of Contra Costa County, it is worth more than 28% 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 309 Alta St, Brentwood, CA?

The 2025 property tax bill for 309 Alta St, Brentwood, CA was $7,482. The county assessed it at $524,034.

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