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Duplex (2 Units, Any Combination)Residential
Last sold for $230,000 on Apr 2, 2004

21 UNDERWOOD ST

BELMONT, MA 02478
4
Beds
2
Baths
2,432 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.
0.13 ac
Lot SizeThe size of the land the home sits on, from county records.
1928
Year BuiltThe year the home was originally built, according to county records.
2
StoriesHow many floors the home has above ground.
10
RoomsThe total room count in county records. Counties differ on which rooms they count, so compare it loosely.

Valuation

Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$230,000 · Apr 2, 2004

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$13,497 (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.$1,185,000 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$765,000
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$420,000
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$1,046,000

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Duplex (2 Units, Any Combination)
StyleThe architectural style of the home, such as ranch or colonial.Colonial
CountyMiddlesex
Lot (acres)The size of the land the home sits on, from county records.0.13
ConstructionThe main material the home's frame and walls are built from.Frame (Unspecified)
HeatingThe type of heating system in the home.Steam
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
Belmont High SchoolA+
High · Grades 9–12 · 0.2 mi
E
Mary Lee BurbankA+
Elementary · Grades KG–3 · 0.3 mi
M
Winthrop L Chenery Upper Elementary SchoolA-
Middle · Grades 4–6 · 0.7 mi

District: Belmont School District

Neighborhood · ZIP 02478These 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.55
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 100.74

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.28%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.3.8%
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.27,636
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.5,959 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$162,650
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$213,185
Average tempThe average temperature here across a full year.49°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

21 Underwood 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.

  • Bigger than 72% of homes in Middlesex County
  • Has a smaller lot than 79% of homes in Middlesex County
  • Older than 71% of homes in Middlesex County

How it measures up in Belmont 02478

The dot is this home. The mark in the middle is the typical home in Belmont 02478.

Living area2,432 ft²
SmallerTypical 2,124 ft²Bigger

Bigger than 65% of homes nearby

Lot size0.13 ac
SmallerTypical 0.16 acBigger

Bigger than 31% of homes nearby

Year built1928
OlderTypical 1930Newer

Newer than 46% of homes nearby

How 21 Underwood St ranks against every home in each area.
MeasureThis homeBelmont 02478Middlesex County
Living areabigger than2,432 ft²65% of homes72% of homes
Lot sizebigger than0.13 ac31% of homes21% of homes
Year builtnewer than192846% of homes29% of homes

About 21 Underwood St

When did 21 Underwood St, Belmont, MA last sell?

21 Underwood St, Belmont, MA last sold on Apr 2, 2004 for $230,000, according to the county's recorded deed.

How big is 21 Underwood St, Belmont, MA?

21 Underwood St, Belmont, MA has 4 bedrooms, 2 bathrooms, 2,432 square feet of living space and a 0.13-acre lot.

When was 21 Underwood St, Belmont, MA built?

21 Underwood St, Belmont, MA was built in 1928, making it 98 years old. It is a colonial home. The building has 2 stories.

What schools serve 21 Underwood St, Belmont, MA?

21 Underwood St, Belmont, MA is assigned to Belmont High School (high), rated A+; Mary Lee Burbank (elementary), rated A+; Winthrop L Chenery Upper Elementary School (middle), rated A-. All sit in Belmont School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 21 Underwood St, Belmont, MA compare to other homes in Belmont 02478?

Among the 7,995 homes in Belmont 02478, it is bigger than 65% of them (2,432 ft² against a typical 2,124 ft²), its lot is bigger than 31% of them (0.13 ac against a typical 0.16 ac) and it is newer than 46% of them (1928 against a typical 1930). These shares are recounted nightly from the full county assessor record for each area, not from active listings.

What are the property taxes on 21 Underwood St, Belmont, MA?

The 2025 property tax bill for 21 Underwood St, Belmont, MA was $13,497. The county assessed it at $1,185,000.

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