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Single Family ResidenceResidential
$1,672,857$1,578 / 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 Oct 21, 2026
Last sold for $386,500 on Dec 24, 1998

420 30TH AVE

SAN MATEO, CA 94403
2
Beds
1
Baths
1,060 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.
1941
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

$1.7M
$1.6M low$1.8M high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$386,500 · Dec 24, 1998

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$7,842 (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.$617,606 (2026)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$308,803
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$308,803
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$605,498
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$1,381,680

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.Ranch
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
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(11)

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.

H
Hillsdale High SchoolA-
High · Grades 9–12 · 0.3 mi
M
Abbott Middle SchoolC
Middle · Grades 6–8 · 0.4 mi
E
Laurel Elementary SchoolD
Elementary · Grades KG–5 · 0.5 mi

District: San Mateo-Foster City Elementary School District

Neighborhood · ZIP 94403These 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.104
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.85
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.516

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.34%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.7.9%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.3%
PopulationHow many people live in this area.43,216
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.7,529 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$160,514
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$196,016
Average tempThe average temperature here across a full year.58°F
Annual precipHow much rain and melted snow falls here in a typical year.21 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

420 30th 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 76% of homes in Westwood Knolls
  • Costs more per square foot than 97% of homes in San Mateo 94403
  • Smaller than 94% of homes in Westwood Knolls
  • Has a smaller lot than 89% of homes in Westwood Knolls
  • Older than 91% of homes in San Mateo 94403

What homes are worth in San Mateo 94403

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

This home
$561K$3M

This home is worth more than 48% of homes in San Mateo 94403.

How it measures up in San Mateo 94403

The dot is this home. The mark in the middle is the typical home in San Mateo 94403.

Estimated value$1,672,857
CheaperTypical $1,709,772Pricier

Pricier than 48% of homes nearby

Price per ft²$1578
CheaperTypical $1073Pricier

Pricier than 97% of homes nearby

Living area1,060 ft²
SmallerTypical 1,540 ft²Bigger

Bigger than 15% of homes nearby

Lot size0.12 ac
SmallerTypical 0.14 acBigger

Bigger than 22% of homes nearby

Year built1941
OlderTypical 1955Newer

Newer than 9% of homes nearby

How 420 30th Ave ranks against every home in each area.
MeasureThis homeWestwood KnollsSan Mateo 94403San Mateo County
Estimated valuepricier than$1,672,85724% of homes48% of homes58% of homes
Price per ft²pricier than$157893% of homes97% of homes90% of homes
Living areabigger than1,060 ft²6% of homes15% of homes15% of homes
Lot sizebigger than0.12 ac11% of homes22% of homes31% of homes
Year builtnewer than194128% of homes9% of homes14% of homes

About 420 30th Ave

How much is 420 30th Ave, San Mateo, CA worth?

The TopHap Estimate for 420 30th Ave, San Mateo, CA is $1,672,857 as of Oct 21, 2026. The likely range is $1,566,564 to $1,779,150. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 420 30th Ave, San Mateo, CA last sell?

420 30th Ave, San Mateo, CA last sold on Dec 24, 1998 for $386,500, according to the county's recorded deed. TopHap holds 3 recorded sales for this parcel.

How big is 420 30th Ave, San Mateo, CA?

420 30th Ave, San Mateo, CA has 2 bedrooms, 1 bathrooms, 1,060 square feet of living space and a 0.12-acre lot.

When was 420 30th Ave, San Mateo, CA built?

420 30th Ave, San Mateo, CA was built in 1941, making it 85 years old. It is a ranch home. The building has 1 story.

What schools serve 420 30th Ave, San Mateo, CA?

420 30th Ave, San Mateo, CA is assigned to Hillsdale High School (high), rated A-; Abbott Middle School (middle), rated C; Laurel Elementary School (elementary), rated D. All sit in San Mateo-Foster City Elementary School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 420 30th Ave, San Mateo, CA compare to other homes in San Mateo 94403?

Among the 11,699 homes in San Mateo 94403, it is worth more than 48% of them ($1,672,857 against a typical $1,709,772), its price per square foot is higher than 97% of them ($1578 against a typical $1073), it is bigger than 15% of them (1,060 ft² against a typical 1,540 ft²), its lot is bigger than 22% of them (0.12 ac against a typical 0.14 ac) and it is newer than 9% of them (1941 against a typical 1955). Measured against all of San Mateo County, it is worth more than 58% 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 420 30th Ave, San Mateo, CA?

The 2025 property tax bill for 420 30th Ave, San Mateo, CA was $7,842. The county assessed it at $617,606.

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Assigned schools

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