New London is a town in Merrimack County, New Hampshire, United States. The population was 4,397 at the 2010 census. The town is the home of Colby–Sawyer College.
The town center, where 1,403 people resided at the 2010 census, is defined as the New London census-designated place (CDP), and is located on a hilltop along New Hampshire Route 114 north of Route 11 and Interstate 89.
In 1753, the Masonian Proprietors of Portsmouth, New Hampshire, granted the area now called New London as "Heidelberg". Although it appears on some New Hampshire maps, the township was never settled, and the 1753 grant lapsed into default.
In 1773, roughly the same area was awarded as the "Alexandria Addition" to a new group of speculators, who had previously been granted the adjacent township of Alexandria. These proprietors were led by Jonas Minot of Concord, Massachusetts, but the others were Scotch-Irish immigrants living in Londonderry, New Hampshire. None built dwellings in the Alexandria Addition. Instead they recruited settlers to build roads, mills, schools, and a church—all increasing the value of their land holdings.