U.S. Highway 266 is an east–west United States highway. It is only 43 miles (69 km) long, and lies entirely within the state of Oklahoma. The highway does not meet the former route of its parent, U.S. Highway 66, and is closely paralleled by Interstate 40, which replaced US-266 (along with accompanying routes US-62 from Oklahoma City to Henryetta and US-64 from Warner to the Arkansas border west of Fort Smith, Arkansas) as the major east–west highway east of Oklahoma City during the 1960s.