Radøy is an island municipality in the county of Hordaland, Norway. Radøy was created as a new municipality on 1 January 1964, after the merger of large parts of Hordabø, Manger, and Sæbø, and smaller parts of Austrheim and Lindås.
The Old Norse form of the name was (just) Röð. (The last element øy meaning "island" was added later.) The name is identical with the word röð for "row" (here in the sense "long island").The coat-of-arms is from modern times. They were granted on 16 June 1991. The arms shows two black oarlocks on a yellow field. Oarlocks are on the gunwale of a boat and they support the oar and give force to the rower's stroke. The designer was Even Jarl Skoglund.