Concord (/ˈkɒŋkərd/) is a town in Middlesex County, Massachusetts, United States. In the 2020 census, the town population was 18,491. It contains the census-designated place of West Concord. The United States Census Bureau considers Concord part of Greater Boston. The town center is near where the Sudbury and Assabet rivers join to form the Concord River.
The town was established in 1635 by a group of English settlers; by 1775, the population had grown to 1,400.