The highway's southern terminus is at a signalized intersection with State Route 29, State Route 66, and the eastern terminus of State Route 703 in St. Marys.

Its northern terminus is at another signalized intersection, this time with U.S. Route 127 in the southern end of Van Wert.

State Route 116 travels through the western Ohio counties of Auglaize and Van Wert.

No portion of this route is included within the National Highway System, a network of highways deemed most imperative for the nation's economy, mobility and defense.

[4] State Route 116's designation was assigned in 1923.