South Arnøy or Sørarnøy is an island and a place in Gildeskål. Sørarnøy connected to Nordarnøya the bridge, but none of islands connected to the mainland. The easiest way to get to Sørarnøy is by speedboat or ferry. The boat "Elias Blix II" (named after Elias Blix) also runs passengers to and from Inndyr and Dare.
There are about 300 inhabitants living on the islands. Within the village there are fewer than 200 residents since 2008. There are two grocery shops Sørarnøy, Joker and Service-food. There is bus service between South and North Arnøy approximately two times each day, and school bus every school day between the islands. South Arnøy located on the east side of Sørarnøy.
Large hill is the highest hill on Sørarnøy, it is 52 m.