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Single Family ResidenceResidential
$588,400$287 / 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 92How 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

128 UNION ST

SPEARFISH, SD 57783
6
Baths
2,048 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.
0.23 ac
Lot SizeThe size of the land the home sits on, from county records.
1989
Year BuiltThe year the home was originally built, according to county records.
2
ParkingThe number of parking spaces on the property, including the garage.

Valuation

$588K
$543K low$634K high

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$5,380 (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.$516,670 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$55,300
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$461,370
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$498,280
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$412,560

Climate Risk

Projected Flood DepthHow deep a serious flood is expected to get here at some point in the next 30 years. Shown in inches.27 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.minimal

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
CountyLAWRENCE
Lot (acres)The size of the land the home sits on, from county records.0.23
PoolWhether the property has a pool, and what kind, such as in-ground.No

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

H
Spearfish High School - 01C+
High · Grades 9–12 · 0.2 mi
M
Spearfish Middle School - 05B-
Middle · Grades 6–8 · 0.3 mi
E
West Elementary - 03
Elementary · Grades 1–2 · 0.9 mi

District: Spearfish School District 40-2

Neighborhood · ZIP 57783These 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.105
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.33

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.92%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.31%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.8.4%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.0.6%
PopulationHow many people live in this area.17,419
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.84 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$68,002
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$88,688
Average tempThe average temperature here across a full year.44°F
Annual precipHow much rain and melted snow falls here in a typical year.24 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.63%

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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

128 Union 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.

  • Costs less per square foot than 76% of homes in Spearfish 57783
  • Bigger than 84% of homes in Spearfish 57783
  • Has a smaller lot than 65% of homes in Lawrence County

What homes are worth in Spearfish 57783

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

This home
$255K$1.4M

This home is worth more than 64% of homes in Spearfish 57783.

How it measures up in Spearfish 57783

The dot is this home. The mark in the middle is the typical home in Spearfish 57783.

Estimated value$588,400
CheaperTypical $496,514Pricier

Pricier than 64% of homes nearby

Price per ft²$287
CheaperTypical $346Pricier

Pricier than 24% of homes nearby

Living area2,048 ft²
SmallerTypical 1,368 ft²Bigger

Bigger than 84% of homes nearby

Lot size0.23 ac
SmallerTypical 0.28 acBigger

Bigger than 42% of homes nearby

Year built1989
OlderTypical 1994Newer

Newer than 42% of homes nearby

How 128 Union St ranks against every home in each area.
MeasureThis homeSpearfish 57783Lawrence County
Estimated valuepricier than$588,40064% of homes61% of homes
Price per ft²pricier than$28724% of homes30% of homes
Living areabigger than2,048 ft²84% of homes84% of homes
Lot sizebigger than0.23 ac42% of homes35% of homes
Year builtnewer than198942% of homes48% of homes

About 128 Union St

How much is 128 Union St, Spearfish, SD worth?

The TopHap Estimate for 128 Union St, Spearfish, SD is $588,400 as of Aug 30, 2026. The likely range is $543,024 to $633,776. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 128 Union St, Spearfish, SD last sell?

128 Union St, Spearfish, SD last sold on Jan 1, 1900, according to the county's recorded deed.

How big is 128 Union St, Spearfish, SD?

128 Union St, Spearfish, SD has 6 bathrooms, 2,048 square feet of living space and a 0.23-acre lot.

When was 128 Union St, Spearfish, SD built?

128 Union St, Spearfish, SD was built in 1989, making it 37 years old.

What schools serve 128 Union St, Spearfish, SD?

128 Union St, Spearfish, SD is assigned to Spearfish High School - 01 (high), rated C+; Spearfish Middle School - 05 (middle), rated B-; West Elementary - 03 (elementary). All sit in Spearfish School District 40-2. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 128 Union St, Spearfish, SD compare to other homes in Spearfish 57783?

Among the 7,071 homes in Spearfish 57783, it is worth more than 64% of them ($588,400 against a typical $496,514), its price per square foot is higher than 24% of them ($287 against a typical $346), it is bigger than 84% of them (2,048 ft² against a typical 1,368 ft²), its lot is bigger than 42% of them (0.23 ac against a typical 0.28 ac) and it is newer than 42% of them (1989 against a typical 1994). Measured against all of Lawrence County, it is worth more than 61% 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 128 Union St, Spearfish, SD?

The 2025 property tax bill for 128 Union St, Spearfish, SD was $5,380. The county assessed it at $516,670.

More homes on Union St

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Assigned schools

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