Bluffton is a city in Harrison and Lancaster Townships, Wells County, Indiana, United States. The population was 9,897 at the 2010 census. The city is the county seat of Wells County.
Bluffton is located at 40°44′17″N 85°10′20″W / 40.73806°N 85.17222°W / 40.73806; -85.17222 (40.737991, -85.172223).
According to the United States Census Bureau, the city has a total area of 6.6 square miles (17.1 km²), of which, 6.6 square miles (17.1 km²) of it is land and 0.15% is water.