Portsmouth, New Hampshire Demographics & Population 2026

Population Overview

Portsmouth is a small city located in New Hampshire, within Rockingham County. The total population is 22,545. It ranks as the 7th most populous out of 100 Census-designated places in New Hampshire.

Age Demographics

The median age in Portsmouth is 42.9 years. This is about the same as the state median of 43.3 years. Only 14.0% of residents are under 18, indicating fewer families with children. 11.1% of residents are 75 or older, suggesting a significant retirement-age population with implications for healthcare services and senior housing.

Economy, Income & Housing

The median household income in Portsmouth is $106,219. This is 7% higher than the state median of $99,031. It is also 32% higher than the national median of $80,734. The poverty rate stands at 6.8%. This is 6% lower than the state poverty rate of 7.2%. The unemployment rate is 2.5%. This is 25% lower than the state rate of 3.4%. The median home value is $688,500. Housing costs are 71% higher than the state median of $402,500. The home-value-to-income ratio of 6.5x suggests that housing affordability is a significant concern for many residents. 51.9% of occupied housing units are owner-occupied. This homeownership rate is 29% lower than the state average of 72.8%.

Race & Ethnicity

Portsmouth has a predominantly White (non-Hispanic) population, comprising 86.2% of all residents. Asian residents account for 4.1%. The Black or African American population (0.2%) is well below the state average of 1.3%. The Asian population is significantly higher than the state average (4.1% vs 2.6%).

Education

64.0% of residents aged 25 and older hold a bachelor's degree or higher. This places Portsmouth in the top 10% of all cities in the state for educational attainment. This is 57% higher than the state rate of 40.6%. Nationally, 35.7% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 97.4%. Notably, 23.4% of adults hold a graduate or professional degree, indicating a highly educated workforce.

Data Sources & Methodology

All demographic data for Portsmouth, New Hampshire is sourced from the U.S. Census Bureau's American Community Survey (ACS) 2020–2024 5-Year Estimates. The ACS collects data from approximately 3.5 million households annually and pools five years of responses so that even small communities can be measured, though the margin of error widens as the population falls. Comparisons are made against New Hampshire state averages and national averages calculated from the same dataset. Rankings reflect the city's position among all 100 Census-designated places in New Hampshire. Read more about how these figures are produced on our methodology page, or visit data.census.gov for official data.