Total monthly cost of ownership
Cost to Own a Home in Portsmouth, New Hampshire
A $641,000 home here costs
$4,959per month, all in — with 20% down at today's 6.66% 30-year fixed rate.
A standard mortgage calculator would have told you $3,295. The real number is $1,664 higher every month — 50% more than the payment most buyers budget for.
Where every dollar goes
Only the first line is a mortgage payment. Change any assumption above and every figure below recalculates.
Portsmouth against Rockingham County and New Hampshire
| Measure | Portsmouth | Rockingham County |
|---|---|---|
| Median home value | $640,600 | $461,400 |
| Median property tax | $7,876 | $7,512 |
| Effective tax rate | 1.229% | 1.628% |
| Median gross rent | $1,778 | $1,619 |
| Population | 22,332 | 317,163 |
The weather behind that power bill
Portsmouth sits in Rockingham County, which averages a high of 82.0°F in its hottest month and a low of 14.3°F in its coldest, with 46.3" of precipitation a year and 27% of it in a single three-month stretch. That climate drives 499 cooling and 6,865 heating degree days, which is what sets the $246 electricity line above.
See the full climate breakdown for Rockingham County — month by month temperatures, rainy season timing, snowfall and heating and cooling costs.
Other cities in Rockingham County
Full Rockingham County cost breakdown · Every county in New Hampshire
Common questions
How much does it cost to own a home in Portsmouth?
A $641,000 home in Portsmouth, New Hampshire costs approximately $4,959 per month with 20% down at 6.66%. That is $3,295 principal and interest, $656 property tax, $159 homeowners insurance, $314 utilities and $534 set aside for maintenance.
What is the property tax rate in Portsmouth?
Portsmouth has an effective property tax rate of 1.229%, based on a median home value of $640,600 and median real estate taxes of $7,876. That is lower than the Rockingham County average of 1.628%.
What is the average home price in Portsmouth?
The median owner-occupied home value in Portsmouth, New Hampshire is $640,600, against $461,400 across Rockingham County.
Is it cheaper to rent or buy in Portsmouth?
Median gross rent in Portsmouth is $1,778 a month, against $4,959 to own the median home all in. Renting costs less month to month here, though renting builds no equity.
Sources & methodology
- Median home value, real estate taxes, gross rent and population for Portsmouth — US Census Bureau, American Community Survey ACS 2023 5-Year, place-level tables.
- Homeowners insurance — NAIC average premium for New Hampshire.
- Electricity price — EIA Electric Power Monthly Table 5.6.A.
- Mortgage rate — Freddie Mac PMMS, refreshed weekly.
- Maintenance (1%/yr) and water and sewer ($68/mo) are national estimates. Every assumption above is editable.