How the tax burden divides between residential and non-residential properties
Portsmouth's $10.14 billion tax base is split between residential properties—single-family homes, condos, multi-family units, mobile homes, and vacant residential land—and non-residential properties.
Homeowners collectively pay 62 cents of every property tax dollar. Non-residential properties pay the remaining 38 cents.
For tax purposes, commercial properties include everything that isn't classified as residential:
Note: Pease Airport properties are assessed separately and not included in these figures.
Between FY2021 and FY2025, residential property values rose faster than commercial values. The result: homeowners now carry a larger share of the tax burden than they did four years ago.
A 4-percentage-point shift may sound small, but on a $10 billion tax base, it represents tens of millions of dollars moving from commercial to residential taxpayers.
Portsmouth's total assessed value grew 60% in four years. But that growth wasn't evenly distributed:
Residential values rose 73%—nearly twice the rate of commercial values (43%). When your slice of the pie grows faster than someone else's, you pay a larger share of the bill.
New Hampshire requires cities to revalue all properties at least every five years. Portsmouth's 2024 revaluation was the first since 2019—capturing five years of market changes all at once.
During that time, the housing market surged while some commercial sectors (office, retail, hotels) faced headwinds. The revaluation locked in that disparity.
The top 10 commercial properties—less than 1% of all commercial parcels—contribute over $6.7 million annually. Click any row for details.
The top 100 commercial properties represent just 7% of commercial parcels but account for a disproportionate share of non-residential tax revenue. Utilities, hospitals, and large apartment complexes dominate the list.
We can't control how fast home values appreciate. Market forces drive that. But when residential values rise faster than commercial values, the tax burden shifts onto homeowners—regardless of whether their income has kept pace.
The question isn't whether this shift happened. It did. The question is what, if anything, to do about it.
If the burden is going to sit primarily on residential properties, the most effective lever is adding more residential units.
More homes = more taxpayers. The same city services get supported by more people, reducing pressure on individual bills and helping prevent longtime residents from being priced out by appreciation they didn't create.
This isn't about increasing total tax revenue—it's about distributing the existing burden more broadly.
Large projects completed in 2024–2025 have added to the tax base and helped offset rate increases.
The FY2026 tax rate is $11.51 per $1,000—only 33 cents higher than FY2025. Without new development, it would have been higher.
We have to change distribution. That means:
Your property tax is straightforward:
For FY2025, with a $11.18 rate, a home assessed at $500,000 pays $5,590 annually.
In New Hampshire, property tax is based solely on the assessed value of land and buildings—not on business revenue, profits, or income generated at a location.
Assessors use three methods to determine value:
Unlike some states, New Hampshire uses a single tax rate for all property types. Residential and commercial properties pay the same rate per $1,000 of assessed value.
Policy note: Some states allow "split rates" where commercial properties pay a higher rate than residential. Some tax business equipment and inventory separately. New Hampshire does neither—property value alone determines the tax.
New Hampshire requires cities to revalue all properties at least every five years. Between revaluations, properties are taxed on potentially outdated values—which can create inequities when different property types appreciate at different rates.
Portsmouth's 2024 revaluation was the first since 2019, capturing five years of market changes all at once.
Search assessed values, property details, and tax information for any parcel in Portsmouth.
Official city resources for property assessments, revaluations, and abatements.
Portsmouth offers exemptions for eligible residents including seniors, veterans, and those with disabilities.
Understand how property tax revenue is spent and follow the annual budget process.
Public meetings where tax policy and budget decisions are discussed.