Single Family ResidenceResidential
Last sold for $1,375,000 on Aug 3, 2026
9 WALNUT ST
COS COB, CT 06807
0
Baths
0.52 ac
Lot SizeThe size of the land the home sits on, from county records.
Valuation
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$1,375,000 · Aug 3, 2026
Tax & Assessment
Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$8,825 (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.$714,140 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$584,360
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$129,780
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$714,140
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$499,898
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.44
1
FloodProjected flooding risk from rivers, heavy rain, and storm surge, scored 0 to 100. Higher is riskier.
18
WildfireProjected wildfire risk, scored 0 to 100, based on how much land burns in a typical year. Higher is riskier.
63
HeatProjected heat risk, scored 0 to 100, based on how many extremely hot days a year are expected. Higher is riskier.
96
StormProjected risk from heavy rainstorms, scored 0 to 100, based on how often extreme rainfall is expected. Higher is riskier.
43
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
CountyWESTERN CONNECTICUT
Lot (acres)The size of the land the home sits on, from county records.0.52
PoolWhether the property has a pool, and what kind, such as in-ground.No
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(3)
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.
EMH
North Mianus SchoolA
Elementary · Grades KG–5 · 0.8 mi
Eastern Middle SchoolA+
Middle · Grades 6–8 · 2.4 mi
Greenwich High SchoolA+
High · Grades 9–12 · 2.6 mi
District: Greenwich School District
Neighborhood · ZIP 06807These 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.54
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.112
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.103
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.34%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.6.3%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.0%
PopulationHow many people live in this area.7,630
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.2,321 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$180,144
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$235,340
Average tempThe average temperature here across a full year.52°F
Annual precipHow much rain and melted snow falls here in a typical year.51 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.58%
Owner Tools
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Claim this homeData 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
9 Walnut St 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.
- Has a bigger lot than 69% of homes in Cos Cob 06807
How it measures up in Cos Cob 06807
The dot is this home. The mark in the middle is the typical home in Cos Cob 06807.
Lot size0.52 ac
SmallerTypical 0.29 acBigger
Bigger than 69% of homes nearby
| Measure | This home | Cos Cob 06807 | Western Connecticut County |
|---|---|---|---|
| Lot sizebigger than | 0.52 ac | 69% of homes | 45% of homes |
About 9 Walnut St
When did 9 Walnut St, Cos Cob, CT last sell?
9 Walnut St, Cos Cob, CT last sold on Aug 3, 2026 for $1,375,000, according to the county's recorded deed.
What schools serve 9 Walnut St, Cos Cob, CT?
9 Walnut St, Cos Cob, CT is assigned to North Mianus School (elementary), rated A; Eastern Middle School (middle), rated A+; Greenwich High School (high), rated A+. All sit in Greenwich School District. Attendance boundaries change — confirm with the district before relying on an assignment.
What are the property taxes on 9 Walnut St, Cos Cob, CT?
The 2025 property tax bill for 9 Walnut St, Cos Cob, CT was $8,825. The county assessed it at $714,140.
More homes on Walnut St
Closest homes
- 2 North St$1.5M181 ft · 2 bd · 2 ba · 1,736 ft² · Sold $825K · May 2008
- 3 North St$1.5M185 ft · 2 bd · 1 ba · 1,881 ft² · Sold Jan 1900
- 14 Walnut St$1.5M167 ft · 3 bd · 1.5 ba · 1,898 ft² · Sold $210K · Nov 1993
- 1 North St$1.9M192 ft · 4 bd · 2.5 ba · 2,522 ft² · Sold $2.9M · Mar 2022
- 44 Mimosa Dr$2M211 ft · 5 bd · 4 ba · 2,806 ft² · Sold $400K · Mar 1993
- 3 Walnut St$1.5M184 ft · 3 bd · 2 ba · 1,922 ft² · Sold $1M · Oct 2020
- 460 Valley Rd$1.7M209 ft · 5 bd · 3.5 ba · 2,497 ft² · Sold $290K · May 1998
- 29 Chestnut St$2.1M201 ft · 3 bd · 3.5 ba · 2,956 ft² · Sold Jan 1900
More homes in Cos Cob 06807
- 10 Steep Hollow Ln$2.5M4 bd · 2.5 ba · 3,852 ft² · Sold $2.5M · Sep 2026
- 33 Mead Ave$2.7M4 bd · 4.5 ba · 3,492 ft² · Sold $2.7M · Aug 2026
- 51 Dandy Dr$3.3M4 bd · 3 ba · 3,543 ft² · Sold $3.3M · Aug 2026
- 9 Deluca Dr$2.4M4 bd · 3 ba · 2,620 ft² · Sold $2.4M · Aug 2026
- 4 Cos Cob Ave$1.5M4 bd · 3 ba · 2,720 ft² · Sold $1.5M · Aug 2026
- 86 Dandy Dr$1.9M4 bd · 3.5 ba · 3,546 ft² · Sold $1.9M · Aug 2026
- 12 Old Post Rd$2M4 bd · 2.5 ba · 3,034 ft² · Sold $2M · Aug 2026
- 15 River Rd$918K2 bd · 2 ba · 1,270 ft² · Sold $914K · Aug 2026
- 106 Orchard St$2.5M5 bd · 4.5 ba · 2,939 ft² · Sold $2.5M · Jul 2026
- 681 River Rd$2.5M4 bd · 4.5 ba · 3,826 ft² · Sold $2.4M · Jul 2026
- 500 River Rd$1.2M2 bd · 2 ba · 1,830 ft² · Sold $1.2M · Jul 2026
- 14 Pond Pl$3M3 bd · 2.5 ba · 2,082 ft² · Sold $3M · Jul 2026
Assigned schools
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