New London is a town in Merrimack County, New Hampshire, United States. The population was 4,400 at the 2020 census. The town is the home of Colby–Sawyer College, site of the Gordon Research Conferences since 1947. The town center, where 1,266 people resided at the 2020 census, is defined as the New London census-designated place, and is located on a hilltop along New Hampshire Route 114 north of Route 11 and Interstate 89.