State Route 46 (SR 46) is a 21.074-mile-long (33.915 km) state highway in Cleburne County in the eastern part of the U.S. state of Alabama. The western terminus of the highway is at an intersection with U.S. Route 78 (US 78) (which also carries the unsigned SR 4) in Heflin. The eastern terminus of the route is at the Georgia state line, east of Ranburne, where the roadway continues as Georgia State Route 166. From the late 1920s to the mid-to-late-1930s, the highway was designated as US 78S, a divided U.S. highway. When that highway was decommissioned, it was redesignated as US 78 Alt.