Fountain County lies in the western part of the U.S. state of Indiana on the east side of the Wabash River. The county was officially established in 1826 and was the 53rd in Indiana. The county seat is Covington.

According to the 2000 census, its population was 17,954; the 2010 population was 17,240. The county has eight incorporated towns with a total population of about 9,700, as well as many small unincorporated communities; it is also divided into eleven townships which provide local services. An interstate highway, two U.S. Routes and five Indiana state roads cross the county, as does a major railroad line.