The A.J. Andrus Duplex, also known as the Paul Pritchard Duplex, is a historic building located in Mason City, Iowa, United States. The two story structure was completed in 1921 in the Prairie School style. Its most distinguishing feature is its C-shaped plan.[2] The exterior is composed of brick on the first floor and stucco on the second floor. The duplex has a horizontal emphasis about it with a broad, overhanging hipped roof, and bands of windows. It was listed on the National Register of Historic Places in 1980.[1]