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Single Family ResidenceResidential
$454,302
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 93How 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 $450,000 on May 20, 2026

509 20TH AVE S

ONALASKA, WI 54650
0
Baths
0.22 ac
Lot SizeThe size of the land the home sits on, from county records.

Valuation

$454K
$422K low$487K high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$450,000 · May 20, 2026

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$5,782 (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.$437,800 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$67,100
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$370,700
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$304,000
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$442,900

Climate Risk

Overall riskThe average of the five hazard scores below, on a 0 to 100 scale. Higher means greater projected risk over the coming decades.33
37
FloodProjected flooding risk from rivers, heavy rain, and storm surge, scored 0 to 100. Higher is riskier.
8
WildfireProjected wildfire risk, scored 0 to 100, based on how much land burns in a typical year. Higher is riskier.
62
HeatProjected heat risk, scored 0 to 100, based on how many extremely hot days a year are expected. Higher is riskier.
61
StormProjected risk from heavy rainstorms, scored 0 to 100, based on how often extreme rainfall is expected. Higher is riskier.
1
DroughtProjected water shortage risk, scored 0 to 100. Higher means more strain on the local water supply.
Projected Flood DepthHow deep a serious flood is expected to get here at some point in the next 30 years. Shown in inches.7 in
30-Year Flood ChanceThe chance of at least one serious flood here in the next 30 years, not in any single year.30%
FEMA Flood ZoneFEMA's flood zone for this address. Zones starting with A or V are high risk, and lenders usually require flood insurance there.0.2 percent flood zone

Scores 0–100; higher = greater projected risk.

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Single Family Residence
CountyLA CROSSE
Lot (acres)The size of the land the home sits on, from county records.0.22
PoolWhether the property has a pool, and what kind, such as in-ground.No

Transaction History(5)

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
Eagle Bluff Elementary SchoolA-
Elementary · Grades PK–5 · 0.4 mi
H
Onalaska High SchoolA
High · Grades 9–12 · 1.1 mi
M
Onalaska Middle SchoolC
Middle · Grades 6–8 · 1.5 mi

District: Onalaska School District

Neighborhood · ZIP 54650These 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.65
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.79
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.12

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.24%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.4.2%
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.25,894
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.616 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$87,588
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$111,661
Average tempThe average temperature here across a full year.46°F
Annual precipHow much rain and melted snow falls here in a typical year.33 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.54%

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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 20th Ave S 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 81% of homes in La Crosse County
  • Has a smaller lot than 73% of homes in Onalaska 54650

What homes are worth in Onalaska 54650

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

This home
$203K$866K

This home is worth more than 75% of homes in Onalaska 54650.

How it measures up in Onalaska 54650

The dot is this home. The mark in the middle is the typical home in Onalaska 54650.

Estimated value$454,302
CheaperTypical $353,456Pricier

Pricier than 75% of homes nearby

Lot size0.22 ac
SmallerTypical 0.28 acBigger

Bigger than 27% of homes nearby

How 509 20th Ave S ranks against every home in each area.
MeasureThis homeOnalaska 54650La Crosse County
Estimated valuepricier than$454,30275% of homes81% of homes
Lot sizebigger than0.22 ac27% of homes43% of homes

About 509 20th Ave S

How much is 509 20th Ave S, Onalaska, WI worth?

The TopHap Estimate for 509 20th Ave S, Onalaska, WI is $454,302 as of Sep 24, 2026. The likely range is $421,891 to $486,713. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 509 20th Ave S, Onalaska, WI last sell?

509 20th Ave S, Onalaska, WI last sold on May 20, 2026 for $450,000, according to the county's recorded deed. TopHap holds 2 recorded sales for this parcel.

What schools serve 509 20th Ave S, Onalaska, WI?

509 20th Ave S, Onalaska, WI is assigned to Eagle Bluff Elementary School (elementary), rated A-; Onalaska High School (high), rated A; Onalaska Middle School (middle), rated C. All sit in Onalaska School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 509 20th Ave S, Onalaska, WI compare to other homes in Onalaska 54650?

Among the 7,497 homes in Onalaska 54650, it is worth more than 75% of them ($454,302 against a typical $353,456) and its lot is bigger than 27% of them (0.22 ac against a typical 0.28 ac). Measured against all of La Crosse County, it is worth more than 81% 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 20th Ave S, Onalaska, WI?

The 2025 property tax bill for 509 20th Ave S, Onalaska, WI was $5,782. The county assessed it at $437,800.

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