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Single Family ResidenceResidential
$587,308$381 / 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 98How well the pricing models agreed with each other on this home. Higher means the estimate rests on stronger, more consistent data.· as of Oct 21, 2026
Last sold for $318,000 on Nov 16, 2006

8420 S 121ST ST

SEATTLE, WA 98178
3
Beds
1.8
Baths
1,540 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.
0.14 ac
Lot SizeThe size of the land the home sits on, from county records.
1954
Year BuiltThe year the home was originally built, according to county records.
1
StoriesHow many floors the home has above ground.
1
ParkingThe number of parking spaces on the property, including the garage.

Valuation

$587K
$577K low$597K high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$318,000 · Nov 16, 2006

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$6,792 (2026)
Assessed ValueThe value the county assigns to this home to calculate property tax. It is often lower than what the home would sell for.$557,000 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$266,000
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$291,000
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$573,000
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$557,000

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Single Family Residence
CountyKING
Lot (acres)The size of the land the home sits on, from county records.0.14
HeatingThe type of heating system in the home.Forced Air With Air Conditioning
FireplaceWhether the home has a fireplace, and what kind.Yes
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
FeaturesExtra features found in county records. Records are not complete everywhere, so a missing feature does not always mean the home lacks it.Deck · 220 ft²

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
Bryn Mawr Elementary SchoolD+
Elementary · Grades KG–5 · 0.3 mi
M
Dimmitt Middle SchoolD-
Middle · Grades 6–8 · 0.3 mi
H
Renton High SchoolD
High · Grades 9–12 · 1.1 mi

District: Renton School District

Neighborhood · ZIP 98178These 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.88
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.113
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.285

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.24%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.12%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.3%
PopulationHow many people live in this area.26,556
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.4,215 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$96,863
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$135,182
Average tempThe average temperature here across a full year.52°F
Annual precipHow much rain and melted snow falls here in a typical year.38 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.43%

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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

8420 S 121st 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 less than 83% of homes in Bryn Mawr
  • Costs less per square foot than 76% of homes in King County
  • Smaller than 71% of homes in Bryn Mawr
  • Has a smaller lot than 83% of homes in Bryn Mawr
  • Older than 76% of homes in King County

What homes are worth in Seattle 98178

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

This home
$316K$1.4M

This home is worth more than 34% of homes in Seattle 98178.

How it measures up in Seattle 98178

The dot is this home. The mark in the middle is the typical home in Seattle 98178.

Estimated value$587,308
CheaperTypical $651,936Pricier

Pricier than 34% of homes nearby

Price per ft²$381
CheaperTypical $382Pricier

Pricier than 50% of homes nearby

Living area1,540 ft²
SmallerTypical 1,770 ft²Bigger

Bigger than 39% of homes nearby

Lot size0.14 ac
SmallerTypical 0.17 acBigger

Bigger than 18% of homes nearby

Year built1954
OlderTypical 1955Newer

Newer than 50% of homes nearby

How 8420 S 121st St ranks against every home in each area.
MeasureThis homeBryn MawrSeattle 98178King County
Estimated valuepricier than$587,30817% of homes34% of homes22% of homes
Price per ft²pricier than$38143% of homes50% of homes24% of homes
Living areabigger than1,540 ft²29% of homes39% of homes36% of homes
Lot sizebigger than0.14 ac17% of homes18% of homes26% of homes
Year builtnewer than195456% of homes50% of homes24% of homes

About 8420 S 121st St

How much is 8420 S 121st St, Seattle, WA worth?

The TopHap Estimate for 8420 S 121st St, Seattle, WA is $587,308 as of Oct 21, 2026. The likely range is $577,384 to $597,232. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 8420 S 121st St, Seattle, WA last sell?

8420 S 121st St, Seattle, WA last sold on Nov 16, 2006 for $318,000, according to the county's recorded deed. TopHap holds 3 recorded sales for this parcel.

How big is 8420 S 121st St, Seattle, WA?

8420 S 121st St, Seattle, WA has 3 bedrooms, 1.8 bathrooms, 1,540 square feet of living space and a 0.14-acre lot.

When was 8420 S 121st St, Seattle, WA built?

8420 S 121st St, Seattle, WA was built in 1954, making it 72 years old. The building has 1 story.

What schools serve 8420 S 121st St, Seattle, WA?

8420 S 121st St, Seattle, WA is assigned to Bryn Mawr Elementary School (elementary), rated D+; Dimmitt Middle School (middle), rated D-; Renton High School (high), rated D. All sit in Renton School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 8420 S 121st St, Seattle, WA compare to other homes in Seattle 98178?

Among the 7,752 homes in Seattle 98178, it is worth more than 34% of them ($587,308 against a typical $651,936), its price per square foot is higher than 50% of them ($381 against a typical $382), it is bigger than 39% of them (1,540 ft² against a typical 1,770 ft²), its lot is bigger than 18% of them (0.14 ac against a typical 0.17 ac) and it is newer than 50% of them (1954 against a typical 1955). Measured against all of King County, it is worth more than 22% 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 8420 S 121st St, Seattle, WA?

The 2026 property tax bill for 8420 S 121st St, Seattle, WA was $6,792. The county assessed it at $557,000.

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