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.