At the time it was dissolved, Edøy municipality was 149 square kilometres (58 sq mi).

[2] The parish of Edø (later spelled Edøy) was established as a municipality on 1 January 1838 (see formannskapsdistrikt law).

[3][4] In 2019, archaeologists from the Norwegian Institute for Cultural Heritage Research using large-scale high-resolution georadar technology, determined that a 17 meter long Viking ship was buried near the Edøy Church.

The first element is æðr which means "eider", a common type of sea bird for the area.

On 3 November 1917, a royal resolution changed the spelling of the name of the municipality to Edøy.

[8] The municipal council (Herredsstyre) of Edøy was made up of 17 representatives that were elected to four year terms.