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Single Family ResidenceResidential
$1,314,224$1,123 / 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 81How 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
Last sold for $700,000 on May 27, 2008

823 9TH AVE

SAN MATEO, CA 94402
2
Beds
1.5
Baths
1,170 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.
0.12 ac
Lot SizeThe size of the land the home sits on, from county records.
1940
Year BuiltThe year the home was originally built, according to county records.
1
StoriesHow many floors the home has above ground.
5
RoomsThe total room count in county records. Counties differ on which rooms they count, so compare it loosely.
1
ParkingThe number of parking spaces on the property, including the garage.

Valuation

$1.3M
$1.1M low$1.6M high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$700,000 · May 27, 2008

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$11,856 (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.$937,832 (2026)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$468,916
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$468,916
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$919,444
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$1,386,270

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Single Family Residence
CountySAN MATEO
Lot (acres)The size of the land the home sits on, from county records.0.12
RoofThe main material covering the roof, such as asphalt shingle or tile.Composition Shingle
HeatingThe type of heating system in the home.Central
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, Basement
PoolWhether the property has a pool, and what kind, such as in-ground.No

Transaction History(4)

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
Sunnybrae Elementary SchoolD
Elementary · Grades KG–5 · 0.2 mi
M
Borel Middle SchoolA-
Middle · Grades 6–8 · 1.1 mi
H
Aragon High SchoolA+
High · Grades 9–12 · 1.3 mi

District: San Mateo-Foster City Elementary School District

Neighborhood · ZIP 94402These 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.91
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.88
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.595

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.93%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.31%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.7.4%
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.26,204
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.4,919 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$171,813
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$232,257
Average tempThe average temperature here across a full year.58°F
Annual precipHow much rain and melted snow falls here in a typical year.24 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.66%

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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

823 9th Ave 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 88% of homes in San Mateo 94402
  • Costs less per square foot than 71% of homes in San Mateo 94402
  • Smaller than 92% of homes in San Mateo 94402
  • Has a smaller lot than 75% of homes in San Mateo 94402
  • Older than 87% of homes in San Mateo County

What homes are worth in San Mateo 94402

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

This home
$826K$5.3M

This home is worth more than 12% of homes in San Mateo 94402.

How it measures up in San Mateo 94402

The dot is this home. The mark in the middle is the typical home in San Mateo 94402.

Estimated value$1,314,224
CheaperTypical $2,372,455Pricier

Pricier than 12% of homes nearby

Price per ft²$1123
CheaperTypical $1242Pricier

Pricier than 29% of homes nearby

Living area1,170 ft²
SmallerTypical 1,920 ft²Bigger

Bigger than 8% of homes nearby

Lot size0.12 ac
SmallerTypical 0.16 acBigger

Bigger than 25% of homes nearby

Year built1940
OlderTypical 1950Newer

Newer than 31% of homes nearby

How 823 9th Ave ranks against every home in each area.
MeasureThis homeSunnybrae / 19th Ave. ParkSan Mateo 94402San Mateo County
Estimated valuepricier than$1,314,22424% of homes12% of homes42% of homes
Price per ft²pricier than$112339% of homes29% of homes65% of homes
Living areabigger than1,170 ft²19% of homes8% of homes23% of homes
Lot sizebigger than0.12 ac56% of homes25% of homes33% of homes
Year builtnewer than194032% of homes31% of homes13% of homes

About 823 9th Ave

How much is 823 9th Ave, San Mateo, CA worth?

The TopHap Estimate for 823 9th Ave, San Mateo, CA is $1,314,224 as of Sep 24, 2026. The likely range is $1,065,267 to $1,563,181. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 823 9th Ave, San Mateo, CA last sell?

823 9th Ave, San Mateo, CA last sold on May 27, 2008 for $700,000, according to the county's recorded deed. TopHap holds 4 recorded sales for this parcel.

How big is 823 9th Ave, San Mateo, CA?

823 9th Ave, San Mateo, CA has 2 bedrooms, 1.5 bathrooms, 1,170 square feet of living space and a 0.12-acre lot.

When was 823 9th Ave, San Mateo, CA built?

823 9th Ave, San Mateo, CA was built in 1940, making it 86 years old. The building has 1 story.

What schools serve 823 9th Ave, San Mateo, CA?

823 9th Ave, San Mateo, CA is assigned to Sunnybrae Elementary School (elementary), rated D; Borel Middle School (middle), rated A-; Aragon High School (high), rated A+. All sit in San Mateo-Foster City Elementary School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 823 9th Ave, San Mateo, CA compare to other homes in San Mateo 94402?

Among the 7,885 homes in San Mateo 94402, it is worth more than 12% of them ($1,314,224 against a typical $2,372,455), its price per square foot is higher than 29% of them ($1123 against a typical $1242), it is bigger than 8% of them (1,170 ft² against a typical 1,920 ft²), its lot is bigger than 25% of them (0.12 ac against a typical 0.16 ac) and it is newer than 31% of them (1940 against a typical 1950). Measured against all of San Mateo County, it is worth more than 42% 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 823 9th Ave, San Mateo, CA?

The 2025 property tax bill for 823 9th Ave, San Mateo, CA was $11,856. The county assessed it at $937,832.

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