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Single Family ResidenceResidential
$559,609$348 / 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 92How well the pricing models agreed with each other on this home. Higher means the estimate rests on stronger, more consistent data.· as of Jul 14, 2026

400 UNION AVE

RIVERHEAD, NY 11901
3
Beds
1.5
Baths
1,606 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.
0.14 ac
Lot SizeThe size of the land the home sits on, from county records.
1920
Year BuiltThe year the home was originally built, according to county records.
2
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.

Valuation

$560K
$515K low$604K high

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$6,331 (2024)
Assessed ValueThe value the county assigns to this home to calculate property tax. It is often lower than what the home would sell for.$33,100 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$5,700
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$27,400
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$405,637

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.Colonial
CountySUFFOLK
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.1989
Lot (acres)The size of the land the home sits on, from county records.0.14
HeatingThe type of heating system in the home.Hot Water
PoolWhether the property has a pool, and what kind, such as in-ground.No
ViewThe type of view from the property, or another feature of the site that affects value.Canal
FeaturesExtra features found in county records. Records are not complete everywhere, so a missing feature does not always mean the home lacks it.Porch · 48 ft²

Transaction History(1)

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
Roanoke Avenue SchoolD-
Elementary · Grades PK–4 · 0.3 mi
M
Riverhead Middle SchoolD
Middle · Grades 6–8 · 0.8 mi
H
Riverhead Senior High SchoolC-
High · Grades 9–12 · 1.0 mi

District: Riverhead Central School District

Neighborhood · ZIP 11901These 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.129
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.107
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.50

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.14%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.10%
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.29,638
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.531 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$77,609
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$107,711
Average tempThe average temperature here across a full year.52°F
Annual precipHow much rain and melted snow falls here in a typical year.47 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.58%

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

400 Union 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 81% of homes in Suffolk County
  • Costs less per square foot than 81% of homes in Riverhead 11901
  • Has a smaller lot than 95% of homes in Riverhead
  • Older than 98% of homes in Suffolk County

What homes are worth in Riverhead 11901

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

This home
$354K$1.7M

This home is worth more than 36% of homes in Riverhead 11901.

How it measures up in Riverhead 11901

The dot is this home. The mark in the middle is the typical home in Riverhead 11901.

Estimated value$559,609
CheaperTypical $633,202Pricier

Pricier than 36% of homes nearby

Price per ft²$348
CheaperTypical $423Pricier

Pricier than 19% of homes nearby

Living area1,606 ft²
SmallerTypical 1,382 ft²Bigger

Bigger than 61% of homes nearby

Lot size0.14 ac
SmallerTypical 0.32 acBigger

Bigger than 5% of homes nearby

Year built1920
OlderTypical 1991Newer

Newer than 5% of homes nearby

How 400 Union Ave ranks against every home in each area.
MeasureThis homeRiverheadRiverhead 11901Suffolk County
Estimated valuepricier than$559,60938% of homes36% of homes19% of homes
Price per ft²pricier than$34826% of homes19% of homes26% of homes
Living areabigger than1,606 ft²58% of homes61% of homes45% of homes
Lot sizebigger than0.14 ac5% of homes5% of homes13% of homes
Year builtnewer than19209% of homes5% of homes2% of homes

About 400 Union Ave

How much is 400 Union Ave, Riverhead, NY worth?

The TopHap Estimate for 400 Union Ave, Riverhead, NY is $559,609 as of Jul 14, 2026. The likely range is $515,443 to $603,775. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 400 Union Ave, Riverhead, NY last sell?

400 Union Ave, Riverhead, NY last sold on Jan 1, 1900, according to the county's recorded deed.

How big is 400 Union Ave, Riverhead, NY?

400 Union Ave, Riverhead, NY has 3 bedrooms, 1.5 bathrooms, 1,606 square feet of living space and a 0.14-acre lot.

When was 400 Union Ave, Riverhead, NY built?

400 Union Ave, Riverhead, NY was built in 1920, making it 106 years old. It is a colonial home. The building has 2 stories.

What schools serve 400 Union Ave, Riverhead, NY?

400 Union Ave, Riverhead, NY is assigned to Roanoke Avenue School (elementary), rated D-; Riverhead Middle School (middle), rated D; Riverhead Senior High School (high), rated C-. All sit in Riverhead Central School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 400 Union Ave, Riverhead, NY compare to other homes in Riverhead 11901?

Among the 9,718 homes in Riverhead 11901, it is worth more than 36% of them ($559,609 against a typical $633,202), its price per square foot is higher than 19% of them ($348 against a typical $423), it is bigger than 61% of them (1,606 ft² against a typical 1,382 ft²), its lot is bigger than 5% of them (0.14 ac against a typical 0.32 ac) and it is newer than 5% of them (1920 against a typical 1991). Measured against all of Suffolk County, it is worth more than 19% 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 400 Union Ave, Riverhead, NY?

The 2024 property tax bill for 400 Union Ave, Riverhead, NY was $6,331. The county assessed it at $33,100.

More homes on Union Ave

Closest homes

More homes in Riverhead 11901

Assigned schools

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