State Route 243 (SR 243) is an east–west state highway in the southern portion of the U.S. state of Ohio. The western terminus of SR 243 is at a diamond interchange with the U.S. Route 52 (US 52) in Coal Grove. The eastern terminus of the state highway is at its signalized junction with State Route 7 approximately 1.25 miles (2.01 km) west of Proctorville near the northern banks of the Ohio River.