Plainfield is an unincorporated community in St. Joseph County, Indiana, United States. It is along U.S. Route 20 in the north-central part of Olive Township and is bordered to the south and west by the town of New Carlisle. Via US-20, Plainfield is west of South Bend and east of Michigan City.
Plainfield is located at . Category:Unincorporated communities in St. Joseph County, Indiana Category:Unincorporated communities in Indiana