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Single Family ResidenceResidential
$4,802,999$1,920 / 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 94How 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
Last sold for $4,200,000 on Sep 14, 2021

821 RIVERSIDE DR

LOS ALTOS, CA 94024
4
Beds
3
Baths
2,501 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.
0.27 ac
Lot SizeThe size of the land the home sits on, from county records.
1953
Year BuiltThe year the home was originally built, according to county records.
1
StoriesHow many floors the home has above ground.
8
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

$4.8M
$4.5M low$5.1M high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$4,200,000 · Sep 14, 2021
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.$2,002,999
Est. Lendable EquityThe part of the owner's equity a lender would typically let them borrow against — about 80% of their equity.$1,602,399
Loan-to-ValueHow much is still owed on the home compared to what it is worth. 80% means loans equal 80% of our estimate, so it shifts when the estimate does.58%
1st MortgageA loan still believed to be open on this home, in the order lenders get repaid. The first position is paid back before the second.$2,800,000
UNITED WHOLESALE MORTGAGE · recorded Sep 14, 2021

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$53,169 (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.$4,546,212 (2026)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$3,896,754
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$649,458
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$4,457,072

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.40
42
FloodProjected flooding risk from rivers, heavy rain, and storm surge, scored 0 to 100. Higher is riskier.
32
WildfireProjected wildfire risk, scored 0 to 100, based on how much land burns in a typical year. Higher is riskier.
23
HeatProjected heat risk, scored 0 to 100, based on how many extremely hot days a year are expected. Higher is riskier.
45
StormProjected risk from heavy rainstorms, scored 0 to 100, based on how often extreme rainfall is expected. Higher is riskier.
60
DroughtProjected water shortage risk, scored 0 to 100. Higher means more strain on the local water supply.
Projected Flood DepthHow deep a serious flood is expected to get here at some point in the next 30 years. Shown in inches.9 in
30-Year Flood ChanceThe chance of at least one serious flood here in the next 30 years, not in any single year.30%
FEMA Flood ZoneFEMA's flood zone for this address. Zones starting with A or V are high risk, and lenders usually require flood insurance there.1 percent flood zone

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
StyleThe architectural style of the home, such as ranch or colonial.Custom Design
CountySANTA CLARA
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.2004
Lot (acres)The size of the land the home sits on, from county records.0.27
ConstructionThe main material the home's frame and walls are built from.Wood (Unspecified)
RoofThe main material covering the roof, such as asphalt shingle or tile.Wood Shingle
HeatingThe type of heating system in the home.Forced Air With Air Conditioning
CoolingThe type of cooling or air conditioning in the home.Yes
FireplaceWhether the home has a fireplace, and what kind.Yes
PoolWhether the property has a pool, and what kind, such as in-ground.No

Transaction History(18)

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
Springer Elementary SchoolA+
Elementary · Grades KG–6 · 0.3 mi
M
Georgina P. Blach Junior High SchoolA
Middle · Grades 7–8 · 0.8 mi
H
Los Altos High SchoolA+
High · Grades 9–12 · 1.4 mi

District: Mountain View-los Altos Union School District

Neighborhood · ZIP 94024These 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.35
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.89
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.505

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.95%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.29%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.3.3%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.1%
PopulationHow many people live in this area.22,374
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.3,105 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$257,147
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$366,556
Average tempThe average temperature here across a full year.59°F
Annual precipHow much rain and melted snow falls here in a typical year.22 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.73%

Ownership

OccupancyWhether the owner appears to live here or somewhere else. It is inferred from the mailing address on record.Owner occupied
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

821 Riverside 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 more than 97% of homes in Santa Clara County
  • Costs more per square foot than 95% of homes in Santa Clara County
  • Bigger than 83% of homes in Santa Clara County
  • Has a bigger lot than 89% of homes in Santa Clara County
  • Older than 85% of homes in Santa Clara County

What homes are worth in Los Altos 94024

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

This home
$2.5M$7.6M

This home is worth more than 63% of homes in Los Altos 94024.

How it measures up in Los Altos 94024

The dot is this home. The mark in the middle is the typical home in Los Altos 94024.

Estimated value$4,802,999
CheaperTypical $4,437,480Pricier

Pricier than 63% of homes nearby

Price per ft²$1920
CheaperTypical $1765Pricier

Pricier than 66% of homes nearby

Living area2,501 ft²
SmallerTypical 2,544 ft²Bigger

Bigger than 48% of homes nearby

Lot size0.27 ac
SmallerTypical 0.26 acBigger

Bigger than 56% of homes nearby

Year built1953
OlderTypical 1959Newer

Newer than 29% of homes nearby

How 821 Riverside Dr ranks against every home in each area.
MeasureThis homeCentral Los AltosLos Altos 94024Santa Clara County
Estimated valuepricier than$4,802,99945% of homes63% of homes97% of homes
Price per ft²pricier than$192044% of homes66% of homes95% of homes
Living areabigger than2,501 ft²48% of homes48% of homes83% of homes
Lot sizebigger than0.27 ac61% of homes56% of homes89% of homes
Year builtnewer than195344% of homes29% of homes15% of homes

About 821 Riverside Dr

How much is 821 Riverside Dr, Los Altos, CA worth?

The TopHap Estimate for 821 Riverside Dr, Los Altos, CA is $4,802,999 as of Jul 14, 2026. The likely range is $4,526,829 to $5,079,169. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 821 Riverside Dr, Los Altos, CA last sell?

821 Riverside Dr, Los Altos, CA last sold on Sep 14, 2021 for $4,200,000, according to the county's recorded deed. TopHap holds 2 recorded sales for this parcel.

How big is 821 Riverside Dr, Los Altos, CA?

821 Riverside Dr, Los Altos, CA has 4 bedrooms, 3 bathrooms, 2,501 square feet of living space and a 0.27-acre lot.

When was 821 Riverside Dr, Los Altos, CA built?

821 Riverside Dr, Los Altos, CA was built in 1953, making it 73 years old. It is a custom design home. The building has 1 story.

What schools serve 821 Riverside Dr, Los Altos, CA?

821 Riverside Dr, Los Altos, CA is assigned to Springer Elementary School (elementary), rated A+; Georgina P. Blach Junior High School (middle), rated A; Los Altos High School (high), rated A+. All sit in Mountain View-los Altos Union School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 821 Riverside Dr, Los Altos, CA compare to other homes in Los Altos 94024?

Among the 7,811 homes in Los Altos 94024, it is worth more than 63% of them ($4,802,999 against a typical $4,437,480), its price per square foot is higher than 66% of them ($1920 against a typical $1765), it is bigger than 48% of them (2,501 ft² against a typical 2,544 ft²), its lot is bigger than 56% of them (0.27 ac against a typical 0.26 ac) and it is newer than 29% of them (1953 against a typical 1959). Measured against all of Santa Clara County, it is worth more than 97% 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 821 Riverside Dr, Los Altos, CA?

The 2025 property tax bill for 821 Riverside Dr, Los Altos, CA was $53,169. The county assessed it at $4,546,212.

Closest homes

More homes in Los Altos 94024

Assigned schools

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