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Single Family ResidenceResidential
$849,254$444 / 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 95How 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 $227,000 on Oct 22, 1993

309 POTOMAC ST

ROCKVILLE, MD 20850
2
Baths
1,914 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.
0.5 ac
Lot SizeThe size of the land the home sits on, from county records.
1912
Year BuiltThe year the home was originally built, according to county records.
2
StoriesHow many floors the home has above ground.

Valuation

$849K
$804K low$894K high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$227,000 · Oct 22, 1993
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.$424,704
Est. Lendable EquityThe part of the owner's equity a lender would typically let them borrow against — about 80% of their equity.$339,763
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.46%
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.$256,550
GMAC MORTGAGE CORP · recorded Apr 22, 2004
2nd 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.$168,000
PENTAGON FCU

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$8,962 (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.$664,500 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$396,500
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$268,000
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$676,000
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$664,500

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
Lot (acres)The size of the land the home sits on, from county records.0.50
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.Slate
HeatingThe type of heating system in the home.Baseboard
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 · 276 ft²

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

E
Beall Elementary SchoolB
Elementary · Grades PK–5 · 0.3 mi
M
Julius West Middle SchoolA
Middle · Grades 6–8 · 0.5 mi
H
Richard Montgomery High SchoolA-
High · Grades 9–12 · 0.8 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

309 Potomac 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 71% of homes in Rockville
  • Costs more per square foot than 88% of homes in Rockville 20850
  • Among the largest lots in Rockville
  • Among the oldest homes in Rockville

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
$179K$1.6M

This home is worth more than 63% 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$849,254
CheaperTypical $749,306Pricier

Pricier than 63% of homes nearby

Price per ft²$444
CheaperTypical $339Pricier

Pricier than 88% of homes nearby

Living area1,914 ft²
SmallerTypical 2,022 ft²Bigger

Bigger than 45% of homes nearby

Lot size0.5 ac
SmallerTypical 0.11 acBigger

Bigger than 94% of homes nearby

Year built1912
OlderTypical 1989Newer

Older than almost all homes nearby

How 309 Potomac St ranks against every home in each area.
MeasureThis homeRockvilleRockville 20850Montgomery County
Estimated valuepricier than$849,25471% of homes63% of homes71% of homes
Price per ft²pricier than$44487% of homes88% of homes87% of homes
Living areabigger than1,914 ft²52% of homes45% of homes47% of homes
Lot sizebigger than0.5 acalmost all homes94% of homes89% of homes
Year builtnewer than1912almost no homesalmost no homesalmost no homes

About 309 Potomac St

How much is 309 Potomac St, Rockville, MD worth?

The TopHap Estimate for 309 Potomac St, Rockville, MD is $849,254 as of Jul 14, 2026. The likely range is $804,220 to $894,288. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 309 Potomac St, Rockville, MD last sell?

309 Potomac St, Rockville, MD last sold on Oct 22, 1993 for $227,000, according to the county's recorded deed.

How big is 309 Potomac St, Rockville, MD?

309 Potomac St, Rockville, MD has 2 bathrooms, 1,914 square feet of living space and a 0.50-acre lot.

When was 309 Potomac St, Rockville, MD built?

309 Potomac St, Rockville, MD was built in 1912, making it 114 years old. It is a bi-level home. The building has 2 stories.

What schools serve 309 Potomac St, Rockville, MD?

309 Potomac St, Rockville, MD is assigned to Beall Elementary School (elementary), rated B; Julius West Middle School (middle), rated A; Richard Montgomery 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 309 Potomac St, Rockville, MD compare to other homes in Rockville 20850?

Among the 13,722 homes in Rockville 20850, it is worth more than 63% of them ($849,254 against a typical $749,306), its price per square foot is higher than 88% of them ($444 against a typical $339), it is bigger than 45% of them (1,914 ft² against a typical 2,022 ft²), its lot is bigger than 94% of them (0.5 ac against a typical 0.11 ac) and it is newer than almost none of them (1912 against a typical 1989). Measured against all of Montgomery County, it is worth more than 71% 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 309 Potomac St, Rockville, MD?

The 2025 property tax bill for 309 Potomac St, Rockville, MD was $8,962. The county assessed it at $664,500.

Closest homes

More homes in Rockville 20850

Assigned schools

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