Peterborough is a town in Hillsborough County, New Hampshire, United States. The population was 6,284 at the 2010 census. The central settlement in town, with 3,103 people at the 2010 census, is defined as the Peterborough census-designated place (CDP) and is located along the Contoocook River at the junction of U.S. Route 202 and New Hampshire Route 101. The community is 38 miles (61 km) west of Manchester and 72 miles (116 km) northwest of Boston.
According to the United States Census Bureau, the town has a total area of 38.1 square miles (98.7 km), of which 37.7 square miles (97.7 km) is land and 0.42 square miles (1.1 km) is water, comprising 1.06% of the town. Peterborough is drained by Nubanusit Brook and the Contoocook River. The highest point in Peterborough is South Pack Monadnock Mountain (2,290 feet (698 m) above sea level), in Miller State Park. Peterborough is also home to Edward MacDowell Dam and Lake recreation area, where visitors can walk across the dam, hike, cross-country ski, swim, boat, picnic, play Frisbee golf, horseshoes or other recreational opportunities, many of them disabilities accessible. The town is crossed by U.S. Route 202 and Route 101.
As of the census of 2010, there were 6,284 people, 2,713 households, and 1,629 families residing in the town. The population density was 167.0 people per square mile (64.3/km²). There were 2,956 housing units at an average density of 78.4 per square mile (30.3/km²). The racial makeup of the town was 96.1% White, 1.8% Asian, 0.7% Black or African American, 0.2% Native American, 0.02% Pacific Islander, 0.4% some other race, and 0.8% from two or more races. Hispanic or Latino of any race were 1.4% of the population.
There were 2,713 households, out of which 28.1% had children under the age of 18 living with them, 45.8% were headed by married couples living together, 10.6% had a female householder with no husband present, and 40.0% were non-families. 33.6% of all households were made up of individuals, and 15.2% were someone living alone who was 65 years of age or older. The average household size was 2.24, and the average family size was 2.85.
In the town, the population was spread out with 21.5% under the age of 18, 6.2% from 18 to 24, 19.9% from 25 to 44, 30.3% from 45 to 64, and 22.0% who were 65 years of age or older. The median age was 46.6 years. For every 100 females, there were 86.9 males. For every 100 females age 18 and over, there were 81.7 males.
For the period 2009–2013, the estimated median annual income for a household in the town was $66,026, and the median income for a family was $89,401. Male full-time workers had a median income of $66,314 versus $34,707 for females. The per capita income for the town was $40,385.