Lowell () is a city in Massachusetts, in the United States. With Cambridge, Lowell is one of two traditional seats of Middlesex County, although most county government entities in Massachusetts have been defunct since 1999. With an estimated population of 110,997 in 2019, it was the fourth most populous city in Massachusetts as of the last census and is estimated to be the fifth most populous as of 2018, and the second most populous in the Boston metropolitan statistical area. The city also is part of a smaller Massachusetts statistical area, called Greater Lowell, and of New England's Merrimack Valley region.
Incorporated in 1826 to serve as a mill town, Lowell was named after Francis Cabot Lowell, a local figure in the Industrial Revolution. The city became known as the cradle of the American Industrial Revolution because of its textile mills and factories. Many of Lowell's historic manufacturing sites were later preserved by the National Park Service to create Lowell National Historical Park. During the Cambodian genocide, the city took in an influx of refugees, leading to a Cambodia Town and America's second largest Cambodian-American population.
Lowell is home to two institutions of higher education. UMass Lowell, part of the University of Massachusetts system, has three campuses in the city. Middlesex Community College's two campuses are in Lowell and in the town of Bedford, Massachusetts.