Bluffton, originally known as Shannon, is a village in Allen and Hancock counties in the U.S. state of Ohio. The population was 4,125 at the 2010 census. Bluffton is home to Bluffton University, a four-year educational institution affiliated with Mennonite Church USA. Bluffton is served by the Bluffton general aviation airport. Bluffton participates in the Tree City USA program. The Allen County portion of Bluffton is part of the Lima Metropolitan Statistical Area, while the Hancock County portion is part of the Findlay Micropolitan Statistical Area.