Whitethorn (formerly, Thorn) is an unincorporated community in Humboldt County, California. It is located 9.5 miles (15 km) southwest of Garberville, at an elevation of 1024 feet (312 m), population 817. Whitethorn shares a zip code with Shelter Cove, California. It is located along California's Lost Coast. The ZIP Code is 95589.