Skip to content
Skip to content
TopHapOpen in map
Single Family ResidenceResidential
$1,309,272$585 / 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

321 K ST

SOUTH BOSTON, MA 02127
4
Beds
1.5
Baths
2,238 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.
1,951 ft²
Lot SizeThe size of the land the home sits on, from county records.
1868
Year BuiltThe year the home was originally built, according to county records.
3
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

$1.3M
$1.2M low$1.4M high

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$13,930 (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.$1,202,900 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$431,500
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$771,400
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$1,829,510

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Single Family Residence
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.2009
Lot (acres)The size of the land the home sits on, from county records.0.04
RoofThe main material covering the roof, such as asphalt shingle or tile.Asphalt
HeatingThe type of heating system in the home.Hot Water
FireplaceWhether the home has a fireplace, and what kind.Yes
PoolWhether the property has a pool, and what kind, such as in-ground.No

Transaction History(2)

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
Joseph P. Tynan Elementary SchoolF
Elementary · Grades PK–5 · 0.1 mi
H
Excel High SchoolD-
High · Grades 9–12 · 0.4 mi
M
Oliver Hazard Perry K-8 SchoolB-
Middle · Grades PK–8 · 0.4 mi

District: Boston School District

Neighborhood · ZIP 02127These 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.110
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.102
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.79

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.44%
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.1.4%
PopulationHow many people live in this area.37,644
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.15,131 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$146,200
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$170,961
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%

Owner Tools

Do you own this home?
Claim this home

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

321 K 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 more than 89% of homes in South Boston 02127
  • Costs less per square foot than 95% of homes in South Boston 02127
  • Bigger than 85% of homes in South Boston 02127
  • Has a bigger lot than 77% of homes in South Boston 02127
  • Among the oldest homes in South Boston 02127

What homes are worth in South Boston 02127

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

This home
$440K$1.9M

This home is worth more than 89% of homes in South Boston 02127.

How it measures up in South Boston 02127

The dot is this home. The mark in the middle is the typical home in South Boston 02127.

Estimated value$1,309,272
CheaperTypical $841,754Pricier

Pricier than 89% of homes nearby

Price per ft²$585
CheaperTypical $806Pricier

Pricier than 5% of homes nearby

Living area2,238 ft²
SmallerTypical 1,200 ft²Bigger

Bigger than 85% of homes nearby

Lot size1,951 ft²
SmallerTypical 1,220 ft²Bigger

Bigger than 77% of homes nearby

Year built1868
OlderTypical 1905Newer

Older than almost all homes nearby

How 321 K St ranks against every home in each area.
MeasureThis homeSouth Boston 02127Suffolk County
Estimated valuepricier than$1,309,27289% of homes87% of homes
Price per ft²pricier than$5855% of homes45% of homes
Living areabigger than2,238 ft²85% of homes72% of homes
Lot sizebigger than1,951 ft²77% of homes45% of homes
Year builtnewer than1868almost no homes2% of homes

About 321 K St

How much is 321 K St, South Boston, MA worth?

The TopHap Estimate for 321 K St, South Boston, MA is $1,309,272 as of Sep 24, 2026. The likely range is $1,211,912 to $1,406,632. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 321 K St, South Boston, MA last sell?

321 K St, South Boston, MA last sold on Jan 1, 1900, according to the county's recorded deed.

How big is 321 K St, South Boston, MA?

321 K St, South Boston, MA has 4 bedrooms, 1.5 bathrooms, 2,238 square feet of living space and a 0.04-acre lot.

When was 321 K St, South Boston, MA built?

321 K St, South Boston, MA was built in 1868, making it 158 years old. The building has 3 stories.

What schools serve 321 K St, South Boston, MA?

321 K St, South Boston, MA is assigned to Joseph P. Tynan Elementary School (elementary), rated F; Excel High School (high), rated D-; Oliver Hazard Perry K-8 School (middle), rated B-. All sit in Boston School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 321 K St, South Boston, MA compare to other homes in South Boston 02127?

Among the 11,103 homes in South Boston 02127, it is worth more than 89% of them ($1,309,272 against a typical $841,754), its price per square foot is higher than 5% of them ($585 against a typical $806), it is bigger than 85% of them (2,238 ft² against a typical 1,200 ft²), its lot is bigger than 77% of them (1,951 ft² against a typical 1,220 ft²) and it is newer than almost none of them (1868 against a typical 1905). Measured against all of Suffolk County, it is worth more than 87% 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 321 K St, South Boston, MA?

The 2025 property tax bill for 321 K St, South Boston, MA was $13,930. The county assessed it at $1,202,900.

More homes on K St

Closest homes

More homes in South Boston 02127

Assigned schools

Explore the area

See this home in context

Open 321 K St on TopHap’s interactive map to compare it against every sale nearby, overlay school zones and flood risk, and run a CMA.

Open in map
A flyover of TopHap's photorealistic 3D map, with recorded sale prices pinned to homes
Search any address, city, zip, or county…3D$1.9M$6.25MOpen in map