The western terminus of State Route 274 is at a T-intersection with U.S. Route 127 approximately 4 miles (6.4 km) west of Chickasaw.

Its eastern terminus is at another T-intersection, this time with State Route 273 about 3.5 miles (5.6 km) northeast of Rushsylvania.

State Route 274 traverses portions of Auglaize, Mercer, Shelby and Logan Counties.

No portion of State Route 274 is included within the National Highway System, a system of highways determined to be most important for the economy, mobility and defense of the nation.

[3][4] In 1937, the highway was extended on both ends, on the west to its current western terminus at U.S. Route 127 west of Chickasaw, and on the east to its current eastern endpoint at State Route 273 northeast of Rushsylvania.