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Single Family ResidenceResidential
$440,000$177 / 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 96How 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 $440,000 on May 30, 2025

123 KEYSTONE RIDGE DR

O FALLON, MO 63366
3
Beds
3
Baths
2,480 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.
0.24 ac
Lot SizeThe size of the land the home sits on, from county records.
2018
Year BuiltThe year the home was originally built, according to county records.
1
StoriesHow many floors the home has above ground.
6
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

$440K
$421K low$459K high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$440,000 · May 30, 2025

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$4,581 (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.$73,473 (2026)
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$68,459
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$386,699

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.0.24
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(6)

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
Flint Elementary SchoolA-
Elementary · Grades KG–5 · 4.4 mi
M
Fort Zumwalt North Middle SchoolA-
Middle · Grades 6–8 · 4.4 mi
H
Fort Zumwalt North High SchoolA+
High · Grades 9–12 · 5.9 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

123 Keystone Ridge 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 77% of homes in O Fallon 63366
  • Bigger than 74% of homes in O Fallon 63366
  • Newer than 93% 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
$192K$752K

This home is worth more than 77% 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$440,000
CheaperTypical $350,425Pricier

Pricier than 77% of homes nearby

Price per ft²$177
CheaperTypical $188Pricier

Pricier than 42% of homes nearby

Living area2,480 ft²
SmallerTypical 1,820 ft²Bigger

Bigger than 74% of homes nearby

Lot size0.24 ac
SmallerTypical 0.23 acBigger

Bigger than 57% of homes nearby

Year built2018
OlderTypical 1999Newer

Newer than 93% of homes nearby

How 123 Keystone Ridge Dr ranks against every home in each area.
MeasureThis homeO Fallon 63366St. Charles County
Estimated valuepricier than$440,00077% of homes71% of homes
Price per ft²pricier than$17742% of homes44% of homes
Living areabigger than2,480 ft²74% of homes68% of homes
Lot sizebigger than0.24 ac57% of homes56% of homes
Year builtnewer than201893% of homes92% of homes

About 123 Keystone Ridge Dr

How much is 123 Keystone Ridge Dr, O Fallon, MO worth?

The TopHap Estimate for 123 Keystone Ridge Dr, O Fallon, MO is $440,000 as of Aug 30, 2026. The likely range is $421,228 to $458,772. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 123 Keystone Ridge Dr, O Fallon, MO last sell?

123 Keystone Ridge Dr, O Fallon, MO last sold on May 30, 2025 for $440,000, according to the county's recorded deed. TopHap holds 2 recorded sales for this parcel.

How big is 123 Keystone Ridge Dr, O Fallon, MO?

123 Keystone Ridge Dr, O Fallon, MO has 3 bedrooms, 3 bathrooms, 2,480 square feet of living space and a 0.24-acre lot.

When was 123 Keystone Ridge Dr, O Fallon, MO built?

123 Keystone Ridge Dr, O Fallon, MO was built in 2018, making it 8 years old. It is a ranch home. The building has 1 story.

What schools serve 123 Keystone Ridge Dr, O Fallon, MO?

123 Keystone Ridge Dr, O Fallon, MO is assigned to Flint Elementary School (elementary), rated A-; Fort Zumwalt North Middle School (middle), rated A-; Fort Zumwalt North High School (high), 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 123 Keystone Ridge Dr, 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 77% of them ($440,000 against a typical $350,425), its price per square foot is higher than 42% of them ($177 against a typical $188), it is bigger than 74% of them (2,480 ft² against a typical 1,820 ft²), its lot is bigger than 57% of them (0.24 ac against a typical 0.23 ac) and it is newer than 93% of them (2018 against a typical 1999). Measured against all of St. Charles 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 123 Keystone Ridge Dr, O Fallon, MO?

The 2025 property tax bill for 123 Keystone Ridge Dr, O Fallon, MO was $4,581. The county assessed it at $73,473.

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