For centuries the local economy was dominated by fishing and boat building.

The island of Mjörn, north-east of Tjörn, has large shell banks.

This is a demographic table based on Tjörn Municipality's electoral districts in the 2022 Swedish general election sourced from SVT's election platform, in turn taken from SCB official statistics.

During the summer, the population swells from 10,000 to 20,000 to 30,000 as vacationers arrive for yachting and swimming.

Skärhamn has an ample guest harbour to accommodate yachters travelling along the Swedish west coast.