Manchester is the largest city in the U.S. state of New Hampshire and the largest city of northern New England, an area composed of Vermont, New Hampshire and Maine. It is in Hillsborough County on the banks of the Merrimack River. As of the 2000 census, the city had a total population of 107,007. As of 2004 the population has been estimated by the New Hampshire Office of Energy and Planning to be nearly 110,000. Manchester is the center of the Manchester, NH, New England City and Town Metropolitan Area (NECTA MA), with a population of 176,663.

Incorporated as a city in 1846, Manchester is nicknamed the Queen City. In 1998, it was named the "Number One Small City in the East" by Money magazine. The Mall of New Hampshire, on Manchester's southern fringe, is the city's main retail center.

Historically, Manchester is important as a textile manufacturing center. The world's largest textile factory was once located along the Merrimack River.

Manchester is named after the much bigger city of Manchester, in Lancashire, England.