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CondominiumResidential
$626,819$546 / 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 96How 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 $570,000 on May 28, 2020

27 UNION ST

WATERTOWN, MA 02472
2
Beds
1.5
Baths
1,147 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.
0.11 ac
Lot SizeThe size of the land the home sits on, from county records.
1890
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

$627K
$603K low$651K high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$570,000 · May 28, 2020

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$7,435 (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.$609,400 (2026)
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$609,400
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$634,577

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Condominium
CountyMIDDLESEX
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.Slate
HeatingThe type of heating system in the home.Forced Air With Air Conditioning
PoolWhether the property has a pool, and what kind, such as in-ground.No

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.

H
Watertown High SchoolC+
High · Grades 9–12 · 0.7 mi
M
Watertown Middle SchoolB-
Middle · Grades 6–8 · 0.7 mi
E
Hosmer Elementary SchoolB
Elementary · Grades PK–5 · 1.1 mi

District: Watertown School District

Neighborhood · ZIP 02472These 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.112
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.103
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.71

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.95%
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.6.6%
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.35,928
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.8,689 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$115,227
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$149,103
Average tempThe average temperature here across a full year.50°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%

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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

27 Union 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.

  • Worth less than 73% of homes in Watertown 02472
  • Costs more per square foot than 68% of homes in Middlesex County
  • Smaller than 83% of homes in Middlesex County
  • Has a smaller lot than 89% of homes in Downtown Watertown
  • Older than 93% of homes in Watertown 02472

What homes are worth in Watertown 02472

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

This home
$371K$1.8M

This home is worth more than 27% of homes in Watertown 02472.

How it measures up in Watertown 02472

The dot is this home. The mark in the middle is the typical home in Watertown 02472.

Estimated value$626,819
CheaperTypical $810,690Pricier

Pricier than 27% of homes nearby

Price per ft²$546
CheaperTypical $583Pricier

Pricier than 37% of homes nearby

Living area1,147 ft²
SmallerTypical 1,727 ft²Bigger

Bigger than 23% of homes nearby

Lot size0.11 ac
SmallerTypical 0.14 acBigger

Bigger than 18% of homes nearby

Year built1890
OlderTypical 1930Newer

Newer than 7% of homes nearby

How 27 Union St ranks against every home in each area.
MeasureThis homeDowntown WatertownWatertown 02472Middlesex County
Estimated valuepricier than$626,81961% of homes27% of homes29% of homes
Price per ft²pricier than$54651% of homes37% of homes68% of homes
Living areabigger than1,147 ft²46% of homes23% of homes17% of homes
Lot sizebigger than0.11 ac11% of homes18% of homes13% of homes
Year builtnewer than189010% of homes7% of homes7% of homes

About 27 Union St

How much is 27 Union St, Watertown, MA worth?

The TopHap Estimate for 27 Union St, Watertown, MA is $626,819 as of Oct 21, 2026. The likely range is $602,652 to $650,986. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 27 Union St, Watertown, MA last sell?

27 Union St, Watertown, MA last sold on May 28, 2020 for $570,000, according to the county's recorded deed. TopHap holds 2 recorded sales for this parcel.

How big is 27 Union St, Watertown, MA?

27 Union St, Watertown, MA has 2 bedrooms, 1.5 bathrooms and 1,147 square feet of living space.

When was 27 Union St, Watertown, MA built?

27 Union St, Watertown, MA was built in 1890, making it 136 years old. The building has 2 stories.

What schools serve 27 Union St, Watertown, MA?

27 Union St, Watertown, MA is assigned to Watertown High School (high), rated C+; Watertown Middle School (middle), rated B-; Hosmer Elementary School (elementary), rated B. All sit in Watertown School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 27 Union St, Watertown, MA compare to other homes in Watertown 02472?

Among the 10,041 homes in Watertown 02472, it is worth more than 27% of them ($626,819 against a typical $810,690), its price per square foot is higher than 37% of them ($546 against a typical $583), it is bigger than 23% of them (1,147 ft² against a typical 1,727 ft²), its lot is bigger than 18% of them (0.11 ac against a typical 0.14 ac) and it is newer than 7% of them (1890 against a typical 1930). Measured against all of Middlesex County, it is worth more than 29% 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 27 Union St, Watertown, MA?

The 2026 property tax bill for 27 Union St, Watertown, MA was $7,435. The county assessed it at $609,400.

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