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Single Family ResidenceResidential
$723,799$272 / 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 Aug 30, 2026
Last sold for $530,000 on Oct 26, 2020

21 MONTCLAIR AVE

WALTHAM, MA 02451
3
Beds
1
Baths
2,658 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.
2,914 ft²
Lot SizeThe size of the land the home sits on, from county records.
1960
Year BuiltThe year the home was originally built, according to county records.
1
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.
1
ParkingThe number of parking spaces on the property, including the garage.

Valuation

$724K
$676K low$772K high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$530,000 · Oct 26, 2020

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$5,732 (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.$583,700 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$318,000
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$265,700
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$742,615

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.Ranch
CountyMIDDLESEX
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.1965
Lot (acres)The size of the land the home sits on, from county records.0.07
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.Electric
GarageWhether the property has a garage, and details like whether it is attached to the home.Garage, Basement
PoolWhether the property has a pool, and what kind, such as in-ground.No

Transaction History(18)

Sales and refinances filed with the county for this home. Not every transfer is a normal sale, so check the type before comparing prices.

Foreclosure Filings(1)

Assigned SchoolsThe public schools this address is zoned for. Boundaries change, so confirm with the district before you count on it.

E
Douglas MacArthur Elementary SchoolA
Elementary · Grades KG–5 · 0.5 mi
M
John F. Kennedy Middle SchoolA-
Middle · Grades 6–8 · 0.5 mi
H
Waltham Sr High SchoolC
High · Grades 9–12 · 0.8 mi

District: Waltham School District

Neighborhood · ZIP 02451These 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.84
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.96%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.31%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.7.7%
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.16,966
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.3,036 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$126,384
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$156,140
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 Montclair Ave 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 67% of homes in Piety Corner
  • Costs less per square foot than 98% of homes in Piety Corner
  • Bigger than 83% of homes in Piety Corner
  • Has a smaller lot than 98% of homes in Waltham 02451

What homes are worth in Waltham 02451

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

This home
$404K$1.5M

This home is worth more than 35% of homes in Waltham 02451.

How it measures up in Waltham 02451

The dot is this home. The mark in the middle is the typical home in Waltham 02451.

Estimated value$723,799
CheaperTypical $790,026Pricier

Pricier than 35% of homes nearby

Price per ft²$272
CheaperTypical $472Pricier

Pricier than 2% of homes nearby

Living area2,658 ft²
SmallerTypical 1,778 ft²Bigger

Bigger than 82% of homes nearby

Lot size2,914 ft²
SmallerTypical 0.18 acBigger

Bigger than 2% of homes nearby

Year built1960
OlderTypical 1957Newer

Newer than 58% of homes nearby

How 21 Montclair Ave ranks against every home in each area.
MeasureThis homePiety CornerWaltham 02451Middlesex County
Estimated valuepricier than$723,79933% of homes35% of homes42% of homes
Price per ft²pricier than$2722% of homes2% of homes5% of homes
Living areabigger than2,658 ft²83% of homes82% of homes78% of homes
Lot sizebigger than2,914 ft²3% of homes2% of homes4% of homes
Year builtnewer than196043% of homes58% of homes53% of homes

About 21 Montclair Ave

How much is 21 Montclair Ave, Waltham, MA worth?

The TopHap Estimate for 21 Montclair Ave, Waltham, MA is $723,799 as of Aug 30, 2026. The likely range is $675,922 to $771,676. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 21 Montclair Ave, Waltham, MA last sell?

21 Montclair Ave, Waltham, MA last sold on Oct 26, 2020 for $530,000, according to the county's recorded deed. TopHap holds 7 recorded sales for this parcel.

How big is 21 Montclair Ave, Waltham, MA?

21 Montclair Ave, Waltham, MA has 3 bedrooms, 1 bathrooms, 2,658 square feet of living space and a 0.07-acre lot.

When was 21 Montclair Ave, Waltham, MA built?

21 Montclair Ave, Waltham, MA was built in 1960, making it 66 years old. It is a ranch home. The building has 1 story.

What schools serve 21 Montclair Ave, Waltham, MA?

21 Montclair Ave, Waltham, MA is assigned to Douglas MacArthur Elementary School (elementary), rated A; John F. Kennedy Middle School (middle), rated A-; Waltham Sr High School (high), rated C. All sit in Waltham School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 21 Montclair Ave, Waltham, MA compare to other homes in Waltham 02451?

Among the 4,967 homes in Waltham 02451, it is worth more than 35% of them ($723,799 against a typical $790,026), its price per square foot is higher than 2% of them ($272 against a typical $472), it is bigger than 82% of them (2,658 ft² against a typical 1,778 ft²), its lot is bigger than 2% of them (2,914 ft² against a typical 0.18 ac) and it is newer than 58% of them (1960 against a typical 1957). Measured against all of Middlesex County, it is worth more than 42% 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 Montclair Ave, Waltham, MA?

The 2025 property tax bill for 21 Montclair Ave, Waltham, MA was $5,732. The county assessed it at $583,700.

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