Helton-Mayo Farm is a historic farm and national historic district located in Shawswick Township, Lawrence County, Indiana. The house was built about 1837, and is a 1 1/2-story Federal style, hall and parlor plan brick dwelling. It has a side-gabled roof and rear ell. Also on the property are the contributing Midwest triple portal barn (c. 1835-1845), wellhouse, corn crib, buggy shed, garage (1920s), and round roofed barn (1950). It was listed in the National Register of Historic Places in 1995.