21 Union St
Portsmouth, NH 03801
4 bd 5 ba 2,349 sqft Built 1870 Lot 3,485 sqft multi_family
No recorded sales
Location
Timeline: Sale, Listing & Tax History
Recorded events
No recorded events
No sale or listing events are on file for this property.
Tax assessment history
| Year | Building | Land | Total assessed | Tax paid |
|---|---|---|---|---|
| 2025 | $568,600 | $458,000 | $1,026,600 | $11,816 |
| 2023 | $256,700 | $265,500 | $522,200 | $8,423 |
| 2022 | $339,700 | $265,500 | $605,200 | $9,199 |
| 2021 | $339,700 | $265,500 | $605,200 | $9,096 |
| 2020 | $339,700 | $265,500 | $605,200 | $8,896 |
| 2019 | $306,700 | $265,500 | $572,200 | $8,503 |
| 2018 | $288,900 | $259,500 | $548,400 | $8,687 |
| 2017 | $288,900 | $217,200 | $506,100 | $7,784 |
| 2016 | $210,500 | $164,600 | $375,100 | $6,392 |
| 2015 | $210,500 | $164,600 | $375,100 | $6,298 |
| 2014 | $190,200 | $170,100 | $360,300 | $6,521 |
| 2011 | $186,700 | $170,100 | $356,800 | $6,186 |
| 2007 | $257,700 | $120,500 | $378,200 | $6,180 |
Property facts
Year built
1870
Property type
multi_family
Stories
2
Beds
4
Baths
5
Living area
2,349 sqft
Lot size
3,485 sqft
ZIP code
03801
City
Portsmouth
Street
Union St
Coordinates
43.07244, -70.76688
Comparable properties nearby
Block-level micro-comps
Same street, ±3 house numbers, sold in the last 24 monthsFrequently asked questions
When did 21 Union St last sell?
No public-record sale is on file for 21 Union St.
What is the current tax assessment for 21 Union St?
The most recent total assessment for 21 Union St (year 2025) is $1,026,600 with $11,816 in property tax.
When was 21 Union St built?
21 Union St was built in 1870.
How does 21 Union St compare to others on Union St?
We track 8 other properties on Union St. Browse the list under "Other properties on Union St" to compare beds, baths, and sale history.
What are the property facts for 21 Union St?
21 Union St is a 4 bed, 5 bath, 2,349 sqft, 3,485 sqft lot multi_family.
Is 21 Union St a flip candidate?
No — 21 Union St does not appear in our flips dataset.
Is 21 Union St a tax-appeal candidate?
No — 21 Union St is not currently flagged as a tax-appeal candidate.
Forecast for this area
ZIP-area linear projection — not a per-property automated valuationQuarterly trend
+0.5%
Implied 1-yr
+2.1%
2026 Q3
$1.3M
2026 Q4
$1.31M
ZIP 03801 — Median Price History + Forecast
Explore nearby
Geography
Other properties on Union St