Swannanoa is located in eastern Buncombe County at 35°36′17″N 82°23′17″W (35.604808, -82.387921), between Asheville and Black Mountain. Interstate 40 passes through the main commercial area of Swannanoa, which is focused around the Ingles supermarket and gas station. The old commercial area sits beside an empty lot where the old Beacon Blankets plant once sat. The Beacon Plant was the center of the Swannanoa community, built by the late Charles D. Owen,Sr it was closed in 2002, and burned almost to the ground on September 3, 2003. Swannanoa also has a nickname , that of which is “Swanna-No-Where” . It got its name from being in the outskirts of Asheville N.C.. The local high school is Charles D. Owen High School. Brad Johnson was a graduate of Charles D. Owen High School , he went on to play football for Tampa Bay.
According to the United States Census Bureau, the CDP has a total area of 6.4 square miles (16.7 km2), of which 6.4 square miles (16.6 km2) is land and 0.04 square miles (0.1 km2), or 0.53%, is water.