Fairhaven is a town in Bristol County, Massachusetts, United States. It is located on the South Coast of Massachusetts where the Acushnet River flows into Buzzards Bay, an arm of the Atlantic Ocean. The town shares a harbor with the city of New Bedford, a place well known for its whaling and fishing heritage; consequently, Fairhaven's history, economy, and culture are closely aligned with those of its larger neighbor. The population of Fairhaven was 15,924 at the time of the 2020 census.

Bristol County is a county in the Commonwealth of Massachusetts. As of the 2020 census, the population was 579,200. The shire town is Taunton. Some governmental functions are performed by the Commonwealth of Massachusetts, others by the county, and others by local towns and cities.