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CondominiumResidential

621 Islington St

PORTSMOUTH, NH 03801
1900
Year BuiltThe year the home was originally built, according to county records.
2
StoriesHow many floors the home has above ground.
Built 19007 units911–1,710 ft²
$4.5M
All units combinedThe sum of our current value estimates for every unit in the building — roughly what the whole building's homes are worth together.
$598K
Median unit valueThe middle unit value in this building by our estimate: half the units are worth more, half less.
$576
Median $/ft²The middle price per square foot across the building's units, by our current estimates. Useful for comparing units of different sizes.

+38.2%vs the Portsmouth ZIP median sale $/ft² ($417)

Sales Performance

—
Median sale (12 mo)The middle sale price among this building's units that sold in the last 12 months, from recorded deeds.
—
1-yr changeHow the building's median sale price over the last 12 months compares with the 12 months before that.
0
Sales (12 mo)Units in this building that sold in the last 12 months, from recorded arms-length deeds.
0.0%
Turnover (12 mo)The share of units that changed hands in the last 12 months. Around 4–6% a year is typical; much higher can signal investor churn or a wave of exits.

2 arms-length sales on record for this building.

Unit Mix & Floor PlansThe building's recurring floor plans, found by grouping units with identical beds, baths and square footage in county records. Larger groups are the building's standard layouts; leftover units have one-off sizes.

2 bed
6 units
3 bed
1 unit

Value DistributionHow the building's units spread across value ranges by our current estimates. A wide spread usually means big differences in size, floor or view.

$508K–$525K
2 units
$575K–$598K
2 units
$641K–$641K
1 unit
$711K–$711K
1 unit
$928K–$928K
1 unit

Ownership & Financing

Owner-occupiedThe share of units where the owner lives in the unit, per county records. The rest are second homes or rentals.14%
Company-ownedUnits owned through an LLC, trust, or other company — a rough proxy for investor ownership.43%
Typical owner tenureThe middle number of years since each unit last changed hands — how long the current owners have been in place.6.8 yrs
Cash purchases (5 yrs)The share of purchases in the last 5 years with no mortgage recorded. High cash share is common in second-home and investor buildings.0%
Avg. loan-to-valueAverage current loan balance against unit value across the building. Low numbers mean owners hold lots of equity — a sign of financial stability.53%
Median owner equityThe middle dollar amount of equity (value minus loans) unit owners hold in this building.$595,985
Median tax billThe middle annual property tax bill among the building's units.$6,398
Pre-foreclosure noticesUnits with an active pre-foreclosure or foreclosure notice on file.0

Recent SalesThe latest recorded arms-length sales in the building, newest first.

Unit CSep 25, 2025$582,000Unit AJun 25, 2025$652,000

Values are TopHap estimates, not appraisals. Sales, ownership and tax figures come from recorded county documents via ATTOM and can lag by several weeks.

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Condominium
CountyROCKINGHAM
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
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.

M
Portsmouth Middle SchoolB
Middle · Grades 6–8 · 0.6 mi
H
Portsmouth High SchoolA+
High · Grades 9–12 · 0.8 mi
E
Little Harbour Elementary SchoolA
Elementary · Grades KG–5 · 1.0 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%

All UnitsEvery property record the county has at this street address, such as the units in a condo building. Prices shown are our estimates, not asking prices.

621 Islington St # A
2 bd · 1 ba · 1,000 ft²
$641K
621 Islington St # B
2 bd · 1 ba · 911 ft²
$525K
621 Islington St # C
2 bd · 1.5 ba · 944 ft²
$575K
621 Islington St # D
2 bd · 2.5 ba · 1,417 ft²
$711K
621 Islington St # E
3 bd · 2.5 ba · 1,710 ft²
$928K
621 Islington St # F
2 bd · 1.5 ba · 993 ft²
$598K
621 Islington St
2 bd · 1.5 ba · 1,051 ft²
$508K

Data by ATTOM. Valuations are automated estimates, not appraisals. Photos from Google Street View and may not depict the current property state.

About 621 Islington St

How many units are in 621 Islington St, Portsmouth, NH?

621 Islington St, Portsmouth, NH has 7 residential units across built in 1900, according to county assessor records.

What is a unit at 621 Islington St, Portsmouth, NH worth?

The median TopHap Estimate across the 7 units at 621 Islington St, Portsmouth, NH is $598,071. That works out to $576 per square foot. Units run from 911 to 1,710 square feet. Estimates are modelled from recorded sales and assessments, not appraisals.

Is 621 Islington St, Portsmouth, NH expensive for Portsmouth?

Units at 621 Islington St, Portsmouth, NH carry a median of $576 per square foot, 38% above the Portsmouth median of $417 per square foot.

How often do units sell at 621 Islington St, Portsmouth, NH?

0 units at 621 Islington St, Portsmouth, NH sold in the last 12 months, out of 2 recorded arms-length sales all time. That is a turnover rate of 0.0% of the building per year.

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