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Single Family ResidenceResidential
$548,272$439 / 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 93How well the pricing models agreed with each other on this home. Higher means the estimate rests on stronger, more consistent data.· as of Sep 24, 2026
Last sold for $345,000 on Nov 6, 2018

21A JOHN ST

CHELSEA, MA 02150
2
Beds
2
Baths
1,250 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.
2,193 ft²
Lot SizeThe size of the land the home sits on, from county records.
1910
Year BuiltThe year the home was originally built, according to county records.
2
StoriesHow many floors the home has above ground.
6
RoomsThe total room count in county records. Counties differ on which rooms they count, so compare it loosely.

Valuation

$548K
$508K low$588K high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$345,000 · Nov 6, 2018

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$5,510 (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.$480,000 (2026)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$172,200
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$307,800
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$471,800
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$504,640

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.Conventional
CountySUFFOLK
Lot (acres)The size of the land the home sits on, from county records.0.05
RoofThe main material covering the roof, such as asphalt shingle or tile.Asphalt
HeatingThe type of heating system in the home.Hot Water
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(7)

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.

M
Clark Avenue SchoolF
Middle · Grades 5–8 · 0.3 mi
E
William a Berkowitz Elementary SchoolC+
Elementary · Grades 1–4 · 0.4 mi
H
Chelsea High SchoolD-
High · Grades 9–12 · 0.7 mi

District: Chelsea School District

Neighborhood · ZIP 02150These 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.89
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.105
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.76

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.17%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.16%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.4%
PopulationHow many people live in this area.40,106
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.16,087 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$72,192
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$94,537
Average tempThe average temperature here across a full year.50°F
Annual precipHow much rain and melted snow falls here in a typical year.45 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

21a John 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 76% of homes in Suffolk County
  • Costs less per square foot than 80% of homes in Suffolk County
  • Smaller than 66% of homes in Chelsea 02150
  • Has a smaller lot than 81% of homes in Chelsea 02150

What homes are worth in Chelsea 02150

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

This home
$277K$830K

This home is worth more than 67% of homes in Chelsea 02150.

How it measures up in Chelsea 02150

The dot is this home. The mark in the middle is the typical home in Chelsea 02150.

Estimated value$548,272
CheaperTypical $489,086Pricier

Pricier than 67% of homes nearby

Price per ft²$439
CheaperTypical $437Pricier

Pricier than 51% of homes nearby

Living area1,250 ft²
SmallerTypical 1,739 ft²Bigger

Bigger than 34% of homes nearby

Lot size2,193 ft²
SmallerTypical 3,659 ft²Bigger

Bigger than 19% of homes nearby

Year built1910
OlderTypical 1920Newer

Newer than 43% of homes nearby

How 21a John St ranks against every home in each area.
MeasureThis homeChelsea 02150Suffolk County
Estimated valuepricier than$548,27267% of homes24% of homes
Price per ft²pricier than$43951% of homes20% of homes
Living areabigger than1,250 ft²34% of homes41% of homes
Lot sizebigger than2,193 ft²19% of homes47% of homes
Year builtnewer than191043% of homes45% of homes

About 21a John St

How much is 21a John St, Chelsea, MA worth?

The TopHap Estimate for 21a John St, Chelsea, MA is $548,272 as of Sep 24, 2026. The likely range is $508,265 to $588,279. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 21a John St, Chelsea, MA last sell?

21a John St, Chelsea, MA last sold on Nov 6, 2018 for $345,000, according to the county's recorded deed. TopHap holds 3 recorded sales for this parcel.

How big is 21a John St, Chelsea, MA?

21a John St, Chelsea, MA has 2 bedrooms, 2 bathrooms, 1,250 square feet of living space and a 0.05-acre lot.

When was 21a John St, Chelsea, MA built?

21a John St, Chelsea, MA was built in 1910, making it 116 years old. It is a conventional home. The building has 2 stories.

What schools serve 21a John St, Chelsea, MA?

21a John St, Chelsea, MA is assigned to Clark Avenue School (middle), rated F; William a Berkowitz Elementary School (elementary), rated C+; Chelsea High School (high), rated D-. All sit in Chelsea School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 21a John St, Chelsea, MA compare to other homes in Chelsea 02150?

Among the 5,340 homes in Chelsea 02150, it is worth more than 67% of them ($548,272 against a typical $489,086), its price per square foot is higher than 51% of them ($439 against a typical $437), it is bigger than 34% of them (1,250 ft² against a typical 1,739 ft²), its lot is bigger than 19% of them (2,193 ft² against a typical 3,659 ft²) and it is newer than 43% of them (1910 against a typical 1920). Measured against all of Suffolk County, it is worth more than 24% 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 21a John St, Chelsea, MA?

The 2026 property tax bill for 21a John St, Chelsea, MA was $5,510. The county assessed it at $480,000.

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Assigned schools

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