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Single Family ResidenceResidential
$2,441,673$904 / 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 95How 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 $2,444,000 on Oct 1, 2026

623 CORNWALLIS LN

FOSTER CITY, CA 94404
4
Beds
2.5
Baths
2,700 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.
1979
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

$2.4M
$2.3M low$2.6M high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$2,444,000 · Oct 1, 2026

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$24,621 (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.$2,152,879 (2026)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$1,507,017
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$645,862
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$2,110,667
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$2,709,450

Climate Risk

Projected Flood DepthHow deep a serious flood is expected to get here at some point in the next 30 years. Shown in inches.1 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.Ranch
CountySAN MATEO
Lot (acres)The size of the land the home sits on, from county records.0.12
ConstructionThe main material the home's frame and walls are built from.Frame (Unspecified)
RoofThe main material covering the roof, such as asphalt shingle or tile.Wood 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
Foster City Elementary SchoolA+
Elementary · Grades KG–5 · 0.8 mi
M
Bowditch Middle SchoolA+
Middle · Grades 6–8 · 1.5 mi
H
San Mateo High SchoolA-
High · Grades 9–12 · 4.5 mi

District: San Mateo-Foster City Elementary School District

Neighborhood · ZIP 94404These 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.78
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 100.469

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.94%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.35%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.4.3%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.2%
PopulationHow many people live in this area.34,562
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.7,017 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$165,214
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$197,174
Average tempThe average temperature here across a full year.58°F
Annual precipHow much rain and melted snow falls here in a typical year.18 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

623 Cornwallis Ln 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 92% of homes in San Mateo 94404
  • Costs less per square foot than 79% of homes in Sea Colony
  • Bigger than 95% of homes in San Mateo 94404
  • Newer than 80% of homes in San Mateo County

What homes are worth in San Mateo 94404

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

This home
$585K$2.8M

This home is worth more than 92% of homes in San Mateo 94404.

How it measures up in San Mateo 94404

The dot is this home. The mark in the middle is the typical home in San Mateo 94404.

Estimated value$2,441,673
CheaperTypical $1,551,692Pricier

Pricier than 92% of homes nearby

Price per ft²$904
CheaperTypical $893Pricier

Pricier than 53% of homes nearby

Living area2,700 ft²
SmallerTypical 1,670 ft²Bigger

Bigger than 95% of homes nearby

Lot size0.12 ac
SmallerTypical 0.14 acBigger

Bigger than 38% of homes nearby

Year built1979
OlderTypical 1974Newer

Newer than 75% of homes nearby

How 623 Cornwallis Ln ranks against every home in each area.
MeasureThis homeSea ColonySan Mateo 94404San Mateo County
Estimated valuepricier than$2,441,67374% of homes92% of homes77% of homes
Price per ft²pricier than$90421% of homes53% of homes43% of homes
Living areabigger than2,700 ft²90% of homes95% of homes86% of homes
Lot sizebigger than0.12 ac57% of homes38% of homes37% of homes
Year builtnewer than197932% of homes75% of homes80% of homes

About 623 Cornwallis Ln

How much is 623 Cornwallis Ln, Foster City, CA worth?

The TopHap Estimate for 623 Cornwallis Ln, Foster City, CA is $2,441,673 as of Oct 21, 2026. The likely range is $2,307,667 to $2,575,678. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 623 Cornwallis Ln, Foster City, CA last sell?

623 Cornwallis Ln, Foster City, CA last sold on Oct 1, 2026 for $2,444,000, according to the county's recorded deed. TopHap holds 4 recorded sales for this parcel.

How big is 623 Cornwallis Ln, Foster City, CA?

623 Cornwallis Ln, Foster City, CA has 4 bedrooms, 2.5 bathrooms, 2,700 square feet of living space and a 0.12-acre lot.

When was 623 Cornwallis Ln, Foster City, CA built?

623 Cornwallis Ln, Foster City, CA was built in 1979, making it 47 years old. It is a ranch home. The building has 2 stories.

What schools serve 623 Cornwallis Ln, Foster City, CA?

623 Cornwallis Ln, Foster City, CA is assigned to Foster City Elementary School (elementary), rated A+; Bowditch Middle School (middle), rated A+; San Mateo 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 623 Cornwallis Ln, Foster City, CA compare to other homes in San Mateo 94404?

Among the 10,362 homes in San Mateo 94404, it is worth more than 92% of them ($2,441,673 against a typical $1,551,692), its price per square foot is higher than 53% of them ($904 against a typical $893), it is bigger than 95% of them (2,700 ft² against a typical 1,670 ft²), its lot is bigger than 38% of them (0.12 ac against a typical 0.14 ac) and it is newer than 75% of them (1979 against a typical 1974). Measured against all of San Mateo County, it is worth more than 77% 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 623 Cornwallis Ln, Foster City, CA?

The 2025 property tax bill for 623 Cornwallis Ln, Foster City, CA was $24,621. The county assessed it at $2,152,879.

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