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Single Family ResidenceResidential
$1,607,972$708 / 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 93How 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 $754,000 on Sep 2, 2015

558 UNION ST

PORTSMOUTH, NH 03801
4
Beds
2
Baths
2,272 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.
0.19 ac
Lot SizeThe size of the land the home sits on, from county records.
1939
Year BuiltThe year the home was originally built, according to county records.
2
StoriesHow many floors the home has above ground.
8
RoomsThe total room count in county records. Counties differ on which rooms they count, so compare it loosely.
1
ParkingThe number of parking spaces on the property, including the garage.

Valuation

$1.6M
$1.5M low$1.7M high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$754,000 · Sep 2, 2015

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$14,443 (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.$1,254,800 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$650,400
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$604,400
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$1,393,000
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$1,264,355

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.Cape Cod
CountyROCKINGHAM
Effective Year BuiltAn adjusted build year that accounts for condition and major remodels. A big renovation can make a home count as newer than it is.1990
Lot (acres)The size of the land the home sits on, from county records.0.19
RoofThe main material covering the roof, such as asphalt shingle or tile.Metal
HeatingThe type of heating system in the home.Hot Water
CoolingThe type of cooling or air conditioning in the home.Yes
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

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

H
Portsmouth High SchoolA+
High · Grades 9–12 · 0.5 mi
E
Little Harbour Elementary SchoolA
Elementary · Grades KG–5 · 0.5 mi
M
Portsmouth Middle SchoolB
Middle · Grades 6–8 · 0.5 mi

District: Portsmouth School District

Neighborhood · ZIP 03801These 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.138
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.104
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.98

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.41%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.5.0%
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.24,014
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.808 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$107,161
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$136,932
Average tempThe average temperature here across a full year.48°F
Annual precipHow much rain and melted snow falls here in a typical year.47 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

558 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.

  • Worth more than 97% of homes in Rockingham County
  • Costs more per square foot than 95% of homes in Rockingham County
  • Bigger than 79% of homes in Portsmouth 03801
  • Has a smaller lot than 86% of homes in Rockingham County
  • Older than 89% of homes in Rockingham County

What homes are worth in Portsmouth 03801

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

This home
$276K$2.8M

This home is worth more than 89% of homes in Portsmouth 03801.

How it measures up in Portsmouth 03801

The dot is this home. The mark in the middle is the typical home in Portsmouth 03801.

Estimated value$1,607,972
CheaperTypical $805,469Pricier

Pricier than 89% of homes nearby

Price per ft²$708
CheaperTypical $553Pricier

Pricier than 75% of homes nearby

Living area2,272 ft²
SmallerTypical 1,532 ft²Bigger

Bigger than 79% of homes nearby

Lot size0.19 ac
SmallerTypical 0.22 acBigger

Bigger than 39% of homes nearby

Year built1939
OlderTypical 1962Newer

Newer than 32% of homes nearby

How 558 Union St ranks against every home in each area.
MeasureThis homeWibird AreaPortsmouth 03801Rockingham County
Estimated valuepricier than$1,607,97281% of homes89% of homes97% of homes
Price per ft²pricier than$70856% of homes75% of homes95% of homes
Living areabigger than2,272 ft²77% of homes79% of homes69% of homes
Lot sizebigger than0.19 ac63% of homes39% of homes14% of homes
Year builtnewer than193975% of homes32% of homes11% of homes

About 558 Union St

How much is 558 Union St, Portsmouth, NH worth?

The TopHap Estimate for 558 Union St, Portsmouth, NH is $1,607,972 as of Aug 30, 2026. The likely range is $1,497,230 to $1,718,714. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 558 Union St, Portsmouth, NH last sell?

558 Union St, Portsmouth, NH last sold on Sep 2, 2015 for $754,000, according to the county's recorded deed.

How big is 558 Union St, Portsmouth, NH?

558 Union St, Portsmouth, NH has 4 bedrooms, 2 bathrooms, 2,272 square feet of living space and a 0.19-acre lot.

When was 558 Union St, Portsmouth, NH built?

558 Union St, Portsmouth, NH was built in 1939, making it 87 years old. It is a cape cod home. The building has 2 stories.

What schools serve 558 Union St, Portsmouth, NH?

558 Union St, Portsmouth, NH is assigned to Portsmouth High School (high), rated A+; Little Harbour Elementary School (elementary), rated A; Portsmouth Middle School (middle), rated B. All sit in Portsmouth School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 558 Union St, Portsmouth, NH compare to other homes in Portsmouth 03801?

Among the 8,130 homes in Portsmouth 03801, it is worth more than 89% of them ($1,607,972 against a typical $805,469), its price per square foot is higher than 75% of them ($708 against a typical $553), it is bigger than 79% of them (2,272 ft² against a typical 1,532 ft²), its lot is bigger than 39% of them (0.19 ac against a typical 0.22 ac) and it is newer than 32% of them (1939 against a typical 1962). Measured against all of Rockingham County, it is worth more than 97% 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 558 Union St, Portsmouth, NH?

The 2025 property tax bill for 558 Union St, Portsmouth, NH was $14,443. The county assessed it at $1,254,800.

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