Whitethorn (formerly Thorn) is an unincorporated community in Humboldt County, California, United States.

Some remote areas in northern Mendocino County are also served by this post office and thus have Whitethorn addresses.

They have Whitethorn addresses, but are located in Mendocino County and are part of the Leggett Valley Unified School District.

About 1.5 miles (2.4 km) south of central Whitethorn is Redwoods Monastery, a community of Cistercian nuns.

[6] Federally, Whitethorn is in California's 2nd congressional district, represented by Democrat Jared Huffman.