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Single Family ResidenceResidential
$761,390$361 / 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 84How 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 $745,000 on Jan 16, 2026

21 FLAGG RD

WESTFORD, MA 01886
3
Beds
2.5
Baths
2,108 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.
0.92 ac
Lot SizeThe size of the land the home sits on, from county records.
1972
Year BuiltThe year the home was originally built, according to county records.
2
StoriesHow many floors the home has above ground.
7
RoomsThe total room count in county records. Counties differ on which rooms they count, so compare it loosely.

Valuation

$761K
$637K low$886K high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$745,000 · Jan 16, 2026

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$9,075 (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.$673,700 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$346,500
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$327,200
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$1,036,450

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
CountyMIDDLESEX
Lot (acres)The size of the land the home sits on, from county records.0.92
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.Asphalt
HeatingThe type of heating system in the home.Forced Air With Air Conditioning
CoolingThe type of cooling or air conditioning in the home.Yes
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(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
Westford AcademyA+
High · Grades 9–12 · 0.6 mi
E
Colonel John Robinson Elementary School
Elementary · Grades PK–2 · 0.7 mi
M
Lloyd G. Blanchard Middle SchoolA+
Middle · Grades 6–8 · 1.9 mi

District: Westford School District

Neighborhood · ZIP 01886These 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.19
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.99
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.80

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.93%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.37%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.1.8%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.3%
PopulationHow many people live in this area.25,048
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.803 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$163,754
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$183,117
Average tempThe average temperature here across a full year.48°F
Annual precipHow much rain and melted snow falls here in a typical year.46 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 Flagg Rd 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.

  • Costs less per square foot than 78% of homes in Westford 01886
  • Has a bigger lot than 75% of homes in Middlesex County
  • Newer than 66% of homes in Middlesex County

What homes are worth in Westford 01886

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

This home
$317K$1.5M

This home is worth more than 42% of homes in Westford 01886.

How it measures up in Westford 01886

The dot is this home. The mark in the middle is the typical home in Westford 01886.

Estimated value$761,390
CheaperTypical $822,280Pricier

Pricier than 42% of homes nearby

Price per ft²$361
CheaperTypical $410Pricier

Pricier than 22% of homes nearby

Living area2,108 ft²
SmallerTypical 2,061 ft²Bigger

Bigger than 52% of homes nearby

Lot size0.92 ac
SmallerTypical 0.92 acBigger

Bigger than 47% of homes nearby

Year built1972
OlderTypical 1984Newer

Newer than 36% of homes nearby

How 21 Flagg Rd ranks against every home in each area.
MeasureThis homeWestford 01886Middlesex County
Estimated valuepricier than$761,39042% of homes48% of homes
Price per ft²pricier than$36122% of homes23% of homes
Living areabigger than2,108 ft²52% of homes61% of homes
Lot sizebigger than0.92 ac47% of homes75% of homes
Year builtnewer than197236% of homes66% of homes

About 21 Flagg Rd

How much is 21 Flagg Rd, Westford, MA worth?

The TopHap Estimate for 21 Flagg Rd, Westford, MA is $761,390 as of Sep 24, 2026. The likely range is $637,097 to $885,683. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 21 Flagg Rd, Westford, MA last sell?

21 Flagg Rd, Westford, MA last sold on Jan 16, 2026 for $745,000, according to the county's recorded deed.

How big is 21 Flagg Rd, Westford, MA?

21 Flagg Rd, Westford, MA has 3 bedrooms, 2.5 bathrooms, 2,108 square feet of living space and a 0.92-acre lot.

When was 21 Flagg Rd, Westford, MA built?

21 Flagg Rd, Westford, MA was built in 1972, making it 54 years old. It is a colonial home. The building has 2 stories.

What schools serve 21 Flagg Rd, Westford, MA?

21 Flagg Rd, Westford, MA is assigned to Westford Academy (high), rated A+; Colonel John Robinson Elementary School (elementary); Lloyd G. Blanchard Middle School (middle), rated A+. All sit in Westford School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 21 Flagg Rd, Westford, MA compare to other homes in Westford 01886?

Among the 8,171 homes in Westford 01886, it is worth more than 42% of them ($761,390 against a typical $822,280), its price per square foot is higher than 22% of them ($361 against a typical $410), it is bigger than 52% of them (2,108 ft² against a typical 2,061 ft²), its lot is bigger than 47% of them (0.92 ac against a typical 0.92 ac) and it is newer than 36% of them (1972 against a typical 1984). Measured against all of Middlesex County, it is worth more than 48% 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 21 Flagg Rd, Westford, MA?

The 2025 property tax bill for 21 Flagg Rd, Westford, MA was $9,075. The county assessed it at $673,700.

More homes on Flagg Rd

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