Overhallahus (a house building company) and Pharmaq (a fish vaccine factory) are both located in the municipality.

During the 1960s, there were many municipal mergers across Norway due to the work of the Schei Committee, although Overhalla's borders were only slightly modified.

The municipality of Overhalla today is, however, just a fraction of the old part of what was historically considered œfri hálfa.

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

The official blazon is "Or, sevense crosses gules in annulo" (Norwegian: I gull sju røde kors som danner en sirkel).

The design was inspired by a 1344 seal used by local peasants on a document regarding the coronation of King Håkon Magnusson.

The seal depicts a building topped with a cross similar to those on the coat of arms and at the local Ranem Church.

By the time it reaches the border with Namsos Municipality, the river Namsen is already brackish and influenced by the tides the ocean.

The municipal council (Kommunestyre) of Overhalla is made up of 21 representatives that are elected to four year terms.

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

About 300 square metres (3,200 sq ft) or about one-third of the mound was excavated by the time the dig was concluded (in 2022).