Its western terminus is at an interchange with Interstate 75 in Bowling Green that doubles as the southern terminus of State Route 64, and its eastern terminus is at State Route 19 in Oak Harbor.

For its final 0.4 miles (0.64 km), the route overlaps State Route 163 which continues east.

SR 105 was commissioned in 1923, routed from 4 miles (6.4 km) east of Bowling Green to Oak Harbor along its current alignment.

Its western terminus was at then SR 34, later became U.S. Route 6 (US 6).

[4][5] Between 1967 and 1969, it was extended west to current western terminus, along the former US 6 alignment.