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Single Family ResidenceResidential
$1,874,114$822 / 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 90How 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

17 21ST AVE

ISLE OF PALMS, SC 29451
3
Beds
2.5
Baths
2,279 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.
0.3 ac
Lot SizeThe size of the land the home sits on, from county records.
1976
Year BuiltThe year the home was originally built, according to county records.
2
StoriesHow many floors the home has above ground.

Valuation

$1.9M
$1.7M low$2.1M high

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$1,627 (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.$513,130 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$434,187
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$78,943
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$17,850
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$1,542,100

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.55 in
30-Year Flood ChanceThe chance of at least one serious flood here in the next 30 years, not in any single year.98%

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
CountyCHARLESTON
Lot (acres)The size of the land the home sits on, from county records.0.30
FoundationWhat the home is built on, such as a concrete slab, a crawl space, or a basement.Mat/Raft Foundation (Slab)
RoofThe main material covering the roof, such as asphalt shingle or tile.Asphalt
HeatingThe type of heating system in the home.Forced Air With Air Conditioning
CoolingThe type of cooling or air conditioning in the home.Central
FireplaceWhether the home has a fireplace, and what kind.Yes
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 · 44 ft²Patio · 359 ft²Porch · 360 ft²

Transaction History(3)

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
Sullivan's Island Elementary School
Elementary · Grades PK–5 · 3.9 mi
M
Moultrie Middle SchoolA+
Middle · Grades 6–8 · 5.1 mi
H
Wando High SchoolA
High · Grades 9–12 · 6.7 mi

District: Charleston County School District

Neighborhood · ZIP 29451These 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.130
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.80
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.291

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.55%
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.3.5%
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.5,565
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.443 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$158,034
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$228,227
Average tempThe average temperature here across a full year.65°F
Annual precipHow much rain and melted snow falls here in a typical year.50 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.63%

Owner Tools

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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

17 21st Ave 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 91% of homes in Charleston County
  • Costs more per square foot than 90% of homes in Charleston County
  • Bigger than 71% of homes in Charleston County
  • Older than 82% of homes in Isle of Palms 29451

What homes are worth in Isle of Palms 29451

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

This home
$491K$6.3M

This home is worth more than 54% of homes in Isle of Palms 29451.

How it measures up in Isle of Palms 29451

The dot is this home. The mark in the middle is the typical home in Isle of Palms 29451.

Estimated value$1,874,114
CheaperTypical $1,781,226Pricier

Pricier than 54% of homes nearby

Price per ft²$822
CheaperTypical $901Pricier

Pricier than 36% of homes nearby

Living area2,279 ft²
SmallerTypical 2,054 ft²Bigger

Bigger than 57% of homes nearby

Lot size0.3 ac
SmallerTypical 0.25 acBigger

Bigger than 61% of homes nearby

Year built1976
OlderTypical 1986Newer

Newer than 18% of homes nearby

How 17 21st Ave ranks against every home in each area.
MeasureThis homeIsle of Palms 29451Charleston County
Estimated valuepricier than$1,874,11454% of homes91% of homes
Price per ft²pricier than$82236% of homes90% of homes
Living areabigger than2,279 ft²57% of homes71% of homes
Lot sizebigger than0.3 ac61% of homes64% of homes
Year builtnewer than197618% of homes33% of homes

About 17 21st Ave

How much is 17 21st Ave, Isle Of Palms, SC worth?

The TopHap Estimate for 17 21st Ave, Isle Of Palms, SC is $1,874,114 as of Sep 24, 2026. The likely range is $1,691,482 to $2,056,746. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 17 21st Ave, Isle Of Palms, SC last sell?

17 21st Ave, Isle Of Palms, SC last sold on Jan 1, 1900, according to the county's recorded deed. TopHap holds 2 recorded sales for this parcel.

How big is 17 21st Ave, Isle Of Palms, SC?

17 21st Ave, Isle Of Palms, SC has 3 bedrooms, 2.5 bathrooms, 2,279 square feet of living space and a 0.30-acre lot.

When was 17 21st Ave, Isle Of Palms, SC built?

17 21st Ave, Isle Of Palms, SC was built in 1976, making it 50 years old. The building has 2 stories.

What schools serve 17 21st Ave, Isle Of Palms, SC?

17 21st Ave, Isle Of Palms, SC is assigned to Sullivan's Island Elementary School (elementary); Moultrie Middle School (middle), rated A+; Wando High School (high), rated A. All sit in Charleston County School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 17 21st Ave, Isle Of Palms, SC compare to other homes in Isle of Palms 29451?

Among the 4,578 homes in Isle of Palms 29451, it is worth more than 54% of them ($1,874,114 against a typical $1,781,226), its price per square foot is higher than 36% of them ($822 against a typical $901), it is bigger than 57% of them (2,279 ft² against a typical 2,054 ft²), its lot is bigger than 61% of them (0.3 ac against a typical 0.25 ac) and it is newer than 18% of them (1976 against a typical 1986). Measured against all of Charleston County, it is worth more than 91% 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 17 21st Ave, Isle Of Palms, SC?

The 2025 property tax bill for 17 21st Ave, Isle Of Palms, SC was $1,627. The county assessed it at $513,130.

More homes on 21st Ave

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Assigned schools

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