Sapian (sometimes spelled Sapi-an) is a fourth class municipality in the province of Capiz, Philippines. It belongs to the Second Congressional District of the Province of Capiz.At the 2010 census, Sapian has a total population of 24,779 people, predominantly Catholic.apian Bay which opens up to the Sibuyan Sea is a source of livelihood for many Sapianons. Marine produce from Sapian Bay include green mussels tahong, oyster talaba, lobster and different species of fish,and clams.