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TownhouseResidential
$246,883$217 / 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 97How 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

21 S PROSPECT AVE

BALTIMORE, MD 21228
2
Baths
1,140 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.
1,520 ft²
Lot SizeThe size of the land the home sits on, from county records.
1942
Year BuiltThe year the home was originally built, according to county records.
2
StoriesHow many floors the home has above ground.

Valuation

$247K
$239K low$255K high

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$3,041 (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.$186,700 (2025)
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$181,700
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$196,700

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Townhouse
StyleThe architectural style of the home, such as ranch or colonial.Townhouse
CountyBaltimore
Lot (acres)The size of the land the home sits on, from county records.0.04
HeatingThe type of heating system in the home.Radiant
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
FeaturesExtra features found in county records. Records are not complete everywhere, so a missing feature does not always mean the home lacks it.Porch · 168 ft²

Transaction History(1)

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
Catonsville Elementary SchoolB+
Elementary · Grades PK–5 · 0.7 mi
H
Catonsville High SchoolA-
High · Grades 9–12 · 1.2 mi
M
Arbutus Middle SchoolC+
Middle · Grades 6–8 · 1.9 mi

District: Baltimore County Public Schools

Neighborhood · ZIP 21228These 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.77
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.85
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.40

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.27%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.7.9%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.0.9%
PopulationHow many people live in this area.50,431
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.3,282 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$108,332
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$127,045
Average tempThe average temperature here across a full year.55°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.57%

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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 S Prospect 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 98% of homes in Catonsville 21228
  • Costs less per square foot than 88% of homes in Catonsville 21228
  • Smaller than 84% of homes in Catonsville 21228
  • Has a smaller lot than 97% of homes in Catonsville 21228
  • Older than 87% of homes in Baltimore County

What homes are worth in Catonsville 21228

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

This home
$240K$872K

This home is worth more than 2% of homes in Catonsville 21228.

How it measures up in Catonsville 21228

The dot is this home. The mark in the middle is the typical home in Catonsville 21228.

Estimated value$246,883
CheaperTypical $429,409Pricier

Pricier than 2% of homes nearby

Price per ft²$217
CheaperTypical $271Pricier

Pricier than 12% of homes nearby

Living area1,140 ft²
SmallerTypical 1,508 ft²Bigger

Bigger than 16% of homes nearby

Lot size1,520 ft²
SmallerTypical 0.18 acBigger

Bigger than 3% of homes nearby

Year built1942
OlderTypical 1958Newer

Newer than 20% of homes nearby

How 21 S Prospect Ave ranks against every home in each area.
MeasureThis homeCatonsville 21228Baltimore County
Estimated valuepricier than$246,8832% of homes19% of homes
Price per ft²pricier than$21712% of homes40% of homes
Living areabigger than1,140 ft²16% of homes20% of homes
Lot sizebigger than1,520 ft²3% of homes6% of homes
Year builtnewer than194220% of homes13% of homes

About 21 S Prospect Ave

How much is 21 S Prospect Ave, Baltimore, MD worth?

The TopHap Estimate for 21 S Prospect Ave, Baltimore, MD is $246,883 as of Aug 30, 2026. The likely range is $238,872 to $254,894. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

How big is 21 S Prospect Ave, Baltimore, MD?

21 S Prospect Ave, Baltimore, MD has 2 bathrooms, 1,140 square feet of living space and a 0.04-acre lot.

When was 21 S Prospect Ave, Baltimore, MD built?

21 S Prospect Ave, Baltimore, MD was built in 1942, making it 84 years old. It is a townhouse home. The building has 2 stories.

What schools serve 21 S Prospect Ave, Baltimore, MD?

21 S Prospect Ave, Baltimore, MD is assigned to Catonsville Elementary School (elementary), rated B+; Catonsville High School (high), rated A-; Arbutus Middle School (middle), rated C+. All sit in Baltimore County Public Schools. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 21 S Prospect Ave, Baltimore, MD compare to other homes in Catonsville 21228?

Among the 15,169 homes in Catonsville 21228, it is worth more than 2% of them ($246,883 against a typical $429,409), its price per square foot is higher than 12% of them ($217 against a typical $271), it is bigger than 16% of them (1,140 ft² against a typical 1,508 ft²), its lot is bigger than 3% of them (1,520 ft² against a typical 0.18 ac) and it is newer than 20% of them (1942 against a typical 1958). Measured against all of Baltimore County, it is worth more than 19% 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 S Prospect Ave, Baltimore, MD?

The 2025 property tax bill for 21 S Prospect Ave, Baltimore, MD was $3,041. The county assessed it at $186,700.

More homes on S Prospect Ave

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Assigned schools

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