Nils Reielson Sandal (born 9 June 1950 in Breim) is a Norwegian politician for the Centre Party.
Sandal served as a deputy representative to the Norwegian Parliament from Sogn og Fjordane during the term 1997 - 2001. In the local level, he served as deputy mayor in Gloppen municipality in 1984 - 1986, and then mayor in 1987 - 1999. Following the 2007 elections, Sandal became the new county mayor (fylkesordfører) of Sogn og Fjordane.