Chelmsford, town, Middlesex County, northeastern Massachusetts, near Lowell; incorporated 1655. Chelmsford, settled in the 1630s, is primarily a residential community. Manufactures include textiles and computer hardware and software. It is named for Chelmsford, England, and was once known for its granite quarries. Population 31,174 (1980); 32,383 (1990); 32,388 (1996 estimate).
