The island municipality is located about 15 kilometres (9.3 mi) west of the town of Sandnessjøen.

During the 1960s, there were many municipal mergers across Norway due to the work of the Schei Committee.

On 6 January 1908, a royal resolution changed the spelling of the name of the municipality to Herøy.

The official blazon is "Azure, three oars Or issuant from the base, the central one abased" (Norwegian: I blått tre oppvoksende gull årer, den midterste nedsenket).

The oars have a tincture of Or which means it is commonly colored yellow, but if it is made out of metal, then gold is used.

The blue color in the field symbolizes the importance of the ocean for the island municipality.

[13] The highest point in the municipality is the 119.15-metre (390.9 ft) tall mountain Vardøyfjellet on the island of Vardøya.

The municipal council (Kommunestyre) of Herøy is made up of 19 representatives that are elected to four year terms.

The tables below show the current and historical composition of the council by political party.