Casselton Commercial Historic District is a historic district in Casselton, North Dakota that was listed on the National Register of Historic Places in 1982.
The listing included 16 contributing buildings which historically included a department store, a financial institution, a Masonic meeting hall and other businesses.
The Masonic Block, at 31 Sixth Avenue North was built in 1887 in two parts, the first being a part with four brick pilasters and a pressed metal cornice. The center of the cornice contains the words "MASONIC BLOCK", the date "1887" and a Masonic emblem. A second part was built adjacent, with identical cornice and finial. In 2013, no Masonic lodges were known to be scheduled to meet in the building.