According to the 2010 census, the township has a total area of 66.59 square miles (172.5 km2), of which 66.38 square miles (171.9 km2) (or 99.68%) is land and 0.21 square miles (0.54 km2) (or 0.32%) is water.[5]
(This list is based on USGS data and may include former settlements.)
Cemeteries
The township contains these sixteen cemeteries: Bangle, Colby, Ewing, German Ridge, Guillaume, Jeffries, Jones, Luxenburger, Miller, Rickenbaugh, Senn, Sprinkle, Underhill, Valley, Walker and Woolums.
Prior to 1962, Oil Township had its own high school. The school colors were green and white, and the mascot was the Oilers. That year, it merged into Perry Central High School.[7]