Ambia is a town in Hickory Grove Township, Benton County, Indiana, United States. The population was 239 at the 2010 census. It is part of the Lafayette, Indiana Metropolitan Statistical Area.

Benton County is located in the northwest part of the U.S. state of Indiana, along the border with Illinois. As of 2020, the county's population was 8,719. It contains six incorporated towns as well as several small unincorporated settlements; it is divided into 11 townships which provide local services. The county seat is Fowler.