Larsmo is a municipality in Finland, located on the west coast of the country. Larsmo is situated in Ostrobothnia, along the Gulf of Bothnia. The population of Larsmo is approximately 6,000, while the sub-region has a population of approximately 50,000. It is the 154th most populous municipality in Finland. Larsmo consists of an archipelago of about 360 islands and numerous skerries. The length of the coastline is about 500 kilometres.