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Single Family ResidenceResidential
$1,466,498$291 / 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 85How well the pricing models agreed with each other on this home. Higher means the estimate rests on stronger, more consistent data.· as of Jul 14, 2026
Last sold for $1,165,000 on Feb 12, 2020

9501 MARY KNOLL DR

ROCKVILLE, MD 20850
4.5
Baths
5,045 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.
1.55 ac
Lot SizeThe size of the land the home sits on, from county records.
1988
Year BuiltThe year the home was originally built, according to county records.
2
StoriesHow many floors the home has above ground.
2
ParkingThe number of parking spaces on the property, including the garage.

Valuation

$1.5M
$1.3M low$1.7M high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$1,165,000 · Feb 12, 2020
Est. Owner EquityRoughly how much of the home's value the owner would keep after paying off known loans. It is our estimate minus the loans still owed.$744,371
Est. Lendable EquityThe part of the owner's equity a lender would typically let them borrow against — about 80% of their equity.$595,497
Loan-to-ValueHow much is still owed on the home compared to what it is worth. 80% means loans equal 80% of our estimate, so it shifts when the estimate does.47%
1st MortgageA loan still believed to be open on this home, in the order lenders get repaid. The first position is paid back before the second.$722,127
UNITED WHOLESALE MORTGAGE · recorded Jul 27, 2020

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$14,815 (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.$1,281,433 (2025)
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$1,207,267
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$1,355,600

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.Bi-Level
CountyMONTGOMERY
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.Wood Shingle
HeatingThe type of heating system in the home.Yes
CoolingThe type of cooling or air conditioning in the home.Central
FireplaceWhether the home has a fireplace, and what kind.Yes
GarageWhether the property has a garage, and details like whether it is attached to the home.Garage, Attached
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 · 495 ft²Porch · 260 ft²

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
Lakewood Elementary SchoolA-
Elementary · Grades KG–5 · 0.2 mi
M
Robert Frost Middle SchoolA
Middle · Grades 6–8 · 0.9 mi
H
Thomas S. Wootton High SchoolA+
High · Grades 9–12 · 1.0 mi

District: Montgomery County Public Schools

Neighborhood · ZIP 20850These 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.104
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.89
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.95%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.28%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.7.8%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.0.8%
PopulationHow many people live in this area.51,693
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.3,703 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$126,425
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$154,183
Average tempThe average temperature here across a full year.54°F
Annual precipHow much rain and melted snow falls here in a typical year.43 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.57%

Ownership

OccupancyWhether the owner appears to live here or somewhere else. It is inferred from the mailing address on record.Owner occupied
Company ownedWhether the owner is a company or trust rather than a person.No

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

9501 Mary Knoll Dr 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 95% of homes in Rockville 20850
  • Costs less per square foot than 79% of homes in Rockville 20850
  • Bigger than 94% of homes in Montgomery County
  • Has a bigger lot than 98% of homes in Rockville 20850
  • Newer than 71% of homes in Montgomery County

What homes are worth in Rockville 20850

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

This home
$177K$1.6M

This home is worth more than 95% of homes in Rockville 20850.

How it measures up in Rockville 20850

The dot is this home. The mark in the middle is the typical home in Rockville 20850.

Estimated value$1,466,498
CheaperTypical $747,183Pricier

Pricier than 95% of homes nearby

Price per ft²$291
CheaperTypical $339Pricier

Pricier than 21% of homes nearby

Living area5,045 ft²
SmallerTypical 2,032 ft²Bigger

Bigger than 93% of homes nearby

Lot size1.55 ac
SmallerTypical 0.1 acBigger

Bigger than 98% of homes nearby

Year built1988
OlderTypical 1989Newer

Newer than 50% of homes nearby

How 9501 Mary Knoll Dr ranks against every home in each area.
MeasureThis homeRockville 20850Montgomery County
Estimated valuepricier than$1,466,49895% of homes91% of homes
Price per ft²pricier than$29121% of homes43% of homes
Living areabigger than5,045 ft²93% of homes94% of homes
Lot sizebigger than1.55 ac98% of homes96% of homes
Year builtnewer than198850% of homes71% of homes

About 9501 Mary Knoll Dr

How much is 9501 Mary Knoll Dr, Rockville, MD worth?

The TopHap Estimate for 9501 Mary Knoll Dr, Rockville, MD is $1,466,498 as of Jul 14, 2026. The likely range is $1,250,795 to $1,682,201. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 9501 Mary Knoll Dr, Rockville, MD last sell?

9501 Mary Knoll Dr, Rockville, MD last sold on Feb 12, 2020 for $1,165,000, according to the county's recorded deed. TopHap holds 2 recorded sales for this parcel.

How big is 9501 Mary Knoll Dr, Rockville, MD?

9501 Mary Knoll Dr, Rockville, MD has 4.5 bathrooms and 5,045 square feet of living space.

When was 9501 Mary Knoll Dr, Rockville, MD built?

9501 Mary Knoll Dr, Rockville, MD was built in 1988, making it 38 years old. It is a bi-level home. The building has 2 stories.

What schools serve 9501 Mary Knoll Dr, Rockville, MD?

9501 Mary Knoll Dr, Rockville, MD is assigned to Lakewood Elementary School (elementary), rated A-; Robert Frost Middle School (middle), rated A; Thomas S. Wootton High School (high), rated A+. All sit in Montgomery County Public Schools. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 9501 Mary Knoll Dr, Rockville, MD compare to other homes in Rockville 20850?

Among the 13,722 homes in Rockville 20850, it is worth more than 95% of them ($1,466,498 against a typical $747,183), its price per square foot is higher than 21% of them ($291 against a typical $339), it is bigger than 93% of them (5,045 ft² against a typical 2,032 ft²), its lot is bigger than 98% of them (1.55 ac against a typical 0.1 ac) and it is newer than 50% of them (1988 against a typical 1989). Measured against all of Montgomery County, it is worth more than 91% 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 9501 Mary Knoll Dr, Rockville, MD?

The 2025 property tax bill for 9501 Mary Knoll Dr, Rockville, MD was $14,815. The county assessed it at $1,281,433.

More homes on Mary Knoll Dr

Closest homes

More homes in Rockville 20850

Assigned schools

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