Bluffton, originally known as Shannon, is a village in Allen and Hancock counties in the U.S. state of Ohio. The population was 3,967 at the 2020 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.

Allen County is a county located in the northwestern part of the U.S. state of Ohio. Its county seat and largest city is Lima. The county was created in 1820 and organized in 1831. The county is named in honor of Colonel John Allen, who was killed leading his men at the Battle of Frenchtown during the War of 1812.