Londonderry is a census-designated place (CDP) within the town of Londonderry, New Hampshire, United States. The population of the CDP was 11,645 at the 2020 census, out of 25,826 in the entire town.
Geography
The CDP occupies the more intensively developed eastern and southern parts of the town of Londonderry, including the east half of the historic town center near the top of Moose Hill. The CDP includes the Londonderry town offices (east side of Mammoth Road) but not the Londonderry High School and Middle School complexes (west side of Mammoth Road). The CDP is bordered to the east by the town of Derry, to the southeast by the town of Windham, and to the southwest by the town of Hudson. From the Hudson town line, the CDP boundary follows New Hampshire Route 102 (Nashua Road), New Hampshire Route 128 (Mammoth Road), Stonehenge Road, Interstate 93, and Ash Street to the Derry town line.
New Hampshire Route 102 crosses the CDP, leading northeast to the center of Derry and southwest to Hudson. Route 128 leads north to New Hampshire Route 28 in North Londonderry and south to Lowell, Massachusetts. Manchester is to the north via Routes 128 and 28.
According to the U.S. Census Bureau, the Londonderry CDP has a total area of , of which , or 0.19%, are water. Most of the CDP drains southeast to Beaver Brook, which forms the border with the town of Windham and flows south to the Merrimack River in Lowell, Massachusetts. The southwestern corner of the CDP drains west via Chase Brook to the Merrimack in Litchfield.
Demographics
As of the census of 2010, there were 11,037 people, 3,958 households, and 3,098 families residing in the CDP. There were 4,105 housing units, of which 147, or 3.6%, were vacant. The racial makeup of the CDP was 95.8% white, 0.8% African American, 0.1% Native American, 1.5% Asian, 0.03% Pacific Islander, 0.5% some other race, and 1.4% from two or more races. 2.5% of the population were Hispanic or Latino of any race.
Of the 3,958 households in the CDP, 39.9% had children under the age of 18 living with them, 62.8% were headed by married couples living together, 11.0% had a female householder with no husband present, and 21.7% were non-families. 16.4% of all households were made up of individuals, and 5.5% were someone living alone who was 65 years of age or older. The average household size was 2.79, and the average family size was 3.13.