State Route 43 is a south to north highway in Tennessee that is 56.79 miles (91.39 km) long. It begins in Madison County and ends in Obion County. State Route 43 is little-known by the general public by this designation as it is overlain by U.S. Route 45E for most of its length; the "43" designation is seen largely on mileposts. Two short sections of this route at Martin and South Fulton is fully signed.