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Single Family ResidenceResidential
$369,980$253 / 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 94How 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 $245,000 on Jan 4, 2021

509 RIVERDALE PARK CT

O FALLON, MO 63366
3
Beds
2
Baths
1,462 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.
0.18 ac
Lot SizeThe size of the land the home sits on, from county records.
2014
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.
2
ParkingThe number of parking spaces on the property, including the garage.

Valuation

$370K
$348K low$392K high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$245,000 · Jan 4, 2021

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$3,549 (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.$57,747 (2026)
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$57,048
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$303,931

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
CountyST. CHARLES
Lot (acres)The size of the land the home sits on, from county records.0.18
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

Transaction History(4)

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
Westhoff Elementary SchoolA-
Elementary · Grades KG–5 · 4.6 mi
H
Fort Zumwalt North High SchoolA+
High · Grades 9–12 · 5.6 mi
M
Fort Zumwalt North Middle SchoolA
Middle · Grades 6–8 · 5.7 mi

District: Fort Zumwalt R-Ii School District

Neighborhood · ZIP 63366These 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.86
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.75
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.95

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.97%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.22%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.5.6%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.0%
PopulationHow many people live in this area.53,503
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.756 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$93,639
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$109,885
Average tempThe average temperature here across a full year.55°F
Annual precipHow much rain and melted snow falls here in a typical year.40 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

509 Riverdale Park Ct 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 more per square foot than 93% of homes in St. Charles County
  • Smaller than 75% of homes in St. Charles County
  • Has a smaller lot than 73% of homes in O Fallon 63366
  • Newer than 88% of homes in O Fallon 63366

What homes are worth in O Fallon 63366

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

This home
$198K$790K

This home is worth more than 56% of homes in O Fallon 63366.

How it measures up in O Fallon 63366

The dot is this home. The mark in the middle is the typical home in O Fallon 63366.

Estimated value$369,980
CheaperTypical $350,660Pricier

Pricier than 56% of homes nearby

Price per ft²$253
CheaperTypical $188Pricier

Pricier than 92% of homes nearby

Living area1,462 ft²
SmallerTypical 1,834 ft²Bigger

Bigger than 29% of homes nearby

Lot size0.18 ac
SmallerTypical 0.22 acBigger

Bigger than 27% of homes nearby

Year built2014
OlderTypical 1999Newer

Newer than 88% of homes nearby

How 509 Riverdale Park Ct ranks against every home in each area.
MeasureThis homeO Fallon 63366St. Charles County
Estimated valuepricier than$369,98056% of homes52% of homes
Price per ft²pricier than$25392% of homes93% of homes
Living areabigger than1,462 ft²29% of homes25% of homes
Lot sizebigger than0.18 ac27% of homes31% of homes
Year builtnewer than201488% of homes88% of homes

About 509 Riverdale Park Ct

How much is 509 Riverdale Park Ct, O Fallon, MO worth?

The TopHap Estimate for 509 Riverdale Park Ct, O Fallon, MO is $369,980 as of Sep 24, 2026. The likely range is $347,988 to $391,972. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 509 Riverdale Park Ct, O Fallon, MO last sell?

509 Riverdale Park Ct, O Fallon, MO last sold on Jan 4, 2021 for $245,000, according to the county's recorded deed. TopHap holds 2 recorded sales for this parcel.

How big is 509 Riverdale Park Ct, O Fallon, MO?

509 Riverdale Park Ct, O Fallon, MO has 3 bedrooms, 2 bathrooms, 1,462 square feet of living space and a 0.18-acre lot.

When was 509 Riverdale Park Ct, O Fallon, MO built?

509 Riverdale Park Ct, O Fallon, MO was built in 2014, making it 12 years old. It is a ranch home. The building has 1 story.

What schools serve 509 Riverdale Park Ct, O Fallon, MO?

509 Riverdale Park Ct, O Fallon, MO is assigned to Westhoff Elementary School (elementary), rated A-; Fort Zumwalt North High School (high), rated A+; Fort Zumwalt North Middle School (middle), rated A. All sit in Fort Zumwalt R-Ii School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 509 Riverdale Park Ct, O Fallon, MO compare to other homes in O Fallon 63366?

Among the 17,886 homes in O Fallon 63366, it is worth more than 56% of them ($369,980 against a typical $350,660), its price per square foot is higher than 92% of them ($253 against a typical $188), it is bigger than 29% of them (1,462 ft² against a typical 1,834 ft²), its lot is bigger than 27% of them (0.18 ac against a typical 0.22 ac) and it is newer than 88% of them (2014 against a typical 1999). Measured against all of St. Charles County, it is worth more than 52% 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 509 Riverdale Park Ct, O Fallon, MO?

The 2025 property tax bill for 509 Riverdale Park Ct, O Fallon, MO was $3,549. The county assessed it at $57,747.

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