Long Plains is a rural locality and small township on the northern Adelaide Plains in South Australia, 73 km north of Adelaide. It is divided between the Wakefield Regional Council and the Adelaide Plains Council. The formal boundaries were established in 1997 for the long established local name with respect of the section in the Mallala council; the portion in the Wakefield council was added in January 2000.
Long Plains is on the Adelaide-Port Augusta railway line, between Mallala and Bowmans. From 1917 to 1923 Long Plains was the rail terminus.
The Long Plains Memorial Hall was built in 1923 and commemorates the lives of four local residents who lost their lives in World War I.
Long Plains School opened in 1883 and closed in 1973. A former building at the school, added in the 1950s, is now located at the Mallala Museum.
Long Plains Post Office opened in August 1881 and closed in November 1976. It shared premises with the Long Plains Store.
Long Plains Church of Christ opened in 1903, was destroyed in a severe bushfire in 1948, was rebuilt in 1953 and closed in 1981.
The United Football Club is based at Long Plains. The Club is also home to netball and other sporting clubs.
The Viterra wheat and barley silos and the water tower stand out above the plains.