Arthur is a city in Cass County, North Dakota, United States. The population was 337 at the 2010 census. Arthur was founded in 1881.
According to the United States Census Bureau, the city has a total area of 1.52 square miles (3.94 km2), all land.
As of the census of 2010, there were 337 people, 130 households, and 82 families living in the city. The population density was 221.7 inhabitants per square mile (85.6/km2). There were 144 housing units at an average density of 94.7 per square mile (36.6/km2). The racial makeup of the city was 98.5% White and 1.5% from two or more races. Hispanic or Latino of any race were 0.6% of the population.
There were 130 households, of which 33.1% had children under the age of 18 living with them, 50.0% were married couples living together, 10.0% had a female householder with no husband present, 3.1% had a male householder with no wife present, and 36.9% were non-families. 34.6% of all households were made up of individuals, and 18.5% had someone living alone who was 65 years of age or older.