Skip to content
Skip to content
TopHapOpen in map
Single Family ResidenceResidential
$9,999,999$1,228 / 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 $15,088,000 on Jul 30, 2021

78 MAYO AVE

GREENWICH, CT 06830
7
Beds
6 / 2
Baths
8,141 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.
1 ac
Lot SizeThe size of the land the home sits on, from county records.
1886
Year BuiltThe year the home was originally built, according to county records.
3
StoriesHow many floors the home has above ground.
17
RoomsThe total room count in county records. Counties differ on which rooms they count, so compare it loosely.
3
ParkingThe number of parking spaces on the property, including the garage.

Valuation

$10M
$10M low$10M high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$15,088,000 · Jul 30, 2021

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$109,888 (2026)
Assessed ValueThe value the county assigns to this home to calculate property tax. It is often lower than what the home would sell for.$10,481,450 (2026)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$4,070,920
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$6,410,530
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$7,480,410
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$9,313,656

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.42
1
FloodProjected flooding risk from rivers, heavy rain, and storm surge, scored 0 to 100. Higher is riskier.
4
WildfireProjected wildfire risk, scored 0 to 100, based on how much land burns in a typical year. Higher is riskier.
65
HeatProjected heat risk, scored 0 to 100, based on how many extremely hot days a year are expected. Higher is riskier.
94
StormProjected risk from heavy rainstorms, scored 0 to 100, based on how often extreme rainfall is expected. Higher is riskier.
49
DroughtProjected water shortage risk, scored 0 to 100. Higher means more strain on the local water supply.
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.minimal

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.Victorian
CountyWESTERN CONNECTICUT
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.1960
Lot (acres)The size of the land the home sits on, from county records.1.00
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.Geo-Thermal
CoolingThe type of cooling or air conditioning in the home.Yes
FireplaceWhether the home has a fireplace, and what kind.Yes
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.Pool W/Hot Tub/Spa
FeaturesExtra features found in county records. Records are not complete everywhere, so a missing feature does not always mean the home lacks it.Deck

Transaction History(8)

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
Julian Curtiss SchoolB
Elementary · Grades PK–5 · 1.7 mi
H
Greenwich High SchoolA+
High · Grades 9–12 · 2.3 mi
M
Central Middle SchoolA
Middle · Grades 6–8 · 3.0 mi

District: Greenwich School District

Neighborhood · ZIP 06830These 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.110
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.119
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.104

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.90%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.30%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.7.6%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.0.8%
PopulationHow many people live in this area.27,704
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.1,501 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$168,325
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$273,728
Average tempThe average temperature here across a full year.52°F
Annual precipHow much rain and melted snow falls here in a typical year.50 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.58%

Owner Tools

Do you own this home?
Claim this home

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

78 Mayo 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.

  • Among the most valuable homes in Greenwich 06830
  • Costs more per square foot than 98% of homes in Western Connecticut County
  • Among the largest homes in Western Connecticut County
  • Older than 98% of homes in Greenwich 06830

What homes are worth in Greenwich 06830

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

This home
$640K$10M

This home is worth more than almost all homes in Greenwich 06830.

How it measures up in Greenwich 06830

The dot is this home. The mark in the middle is the typical home in Greenwich 06830.

Estimated value$9,999,999
CheaperTypical $3,088,848Pricier

Pricier than almost all homes nearby

Price per ft²$1228
CheaperTypical $917Pricier

Pricier than 86% of homes nearby

Living area8,141 ft²
SmallerTypical 2,970 ft²Bigger

Bigger than 93% of homes nearby

Lot size1 ac
SmallerTypical 0.46 acBigger

Bigger than 64% of homes nearby

Year built1886
OlderTypical 1956Newer

Newer than 2% of homes nearby

How 78 Mayo Ave ranks against every home in each area.
MeasureThis homeGreenwich 06830Western Connecticut County
Estimated valuepricier than$9,999,999almost all homesalmost all homes
Price per ft²pricier than$122886% of homes98% of homes
Living areabigger than8,141 ft²93% of homesalmost all homes
Lot sizebigger than1 ac64% of homes62% of homes
Year builtnewer than18862% of homes3% of homes

About 78 Mayo Ave

How much is 78 Mayo Ave, Greenwich, CT worth?

The TopHap Estimate for 78 Mayo Ave, Greenwich, CT is $9,999,999 as of Oct 21, 2026. The likely range is $9,999,999 to $9,999,999. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 78 Mayo Ave, Greenwich, CT last sell?

78 Mayo Ave, Greenwich, CT last sold on Jul 30, 2021 for $15,088,000, according to the county's recorded deed.

How big is 78 Mayo Ave, Greenwich, CT?

78 Mayo Ave, Greenwich, CT has 7 bedrooms, 6 bathrooms, 8,141 square feet of living space and a 1.00-acre lot.

When was 78 Mayo Ave, Greenwich, CT built?

78 Mayo Ave, Greenwich, CT was built in 1886, making it 140 years old. It is a victorian home. The building has 3 stories.

What schools serve 78 Mayo Ave, Greenwich, CT?

78 Mayo Ave, Greenwich, CT is assigned to Julian Curtiss School (elementary), rated B; Greenwich High School (high), rated A+; Central Middle School (middle), rated A. All sit in Greenwich School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 78 Mayo Ave, Greenwich, CT compare to other homes in Greenwich 06830?

Among the 6,738 homes in Greenwich 06830, it is worth more than almost all of them ($9,999,999 against a typical $3,088,848), its price per square foot is higher than 86% of them ($1228 against a typical $917), it is bigger than 93% of them (8,141 ft² against a typical 2,970 ft²), its lot is bigger than 64% of them (1 ac against a typical 0.46 ac) and it is newer than 2% of them (1886 against a typical 1956). Measured against all of Western Connecticut County, it is worth more than almost all 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 78 Mayo Ave, Greenwich, CT?

The 2026 property tax bill for 78 Mayo Ave, Greenwich, CT was $109,888. The county assessed it at $10,481,450.

More homes on Mayo Ave

Closest homes

More homes in Greenwich 06830

Assigned schools

Explore the area

See this home in context

Open 78 Mayo Ave on TopHap’s interactive map to compare it against every sale nearby, overlay school zones and flood risk, and run a CMA.

Open in map
A flyover of TopHap's photorealistic 3D map, with recorded sale prices pinned to homes
Search any address, city, zip, or county…3D$1.9M$6.25MOpen in map