Barangay San Antonio

Barangay San Antonio forms part of Bulusan, a municipality in Sorsogon, and is classified as a small barangay.

According to the 2020 Census of Population and Housing conducted by the Philippine Statistics Authority, Barangay San Antonio had a population of 614. This made it the 16th largest of 24 barangays in Bulusan by population, placing it in the middle tier of the municipality. Residents of Barangay San Antonio accounted for approximately 2.57% of the total population of Bulusan, which stood at 23,932 in the same census year.

The barangay recorded 587 residents in the 2015 intercensal count and 614 residents in the 2020 Census — a net change of +4.6%, consistent with a growing settlement. The Philippine Statistics Authority classifies Barangay San Antonio as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

Bulusan is a municipality comprising 24 barangays, and serves as the governing unit directly responsible for local services in Barangay San Antonio, including public health, sanitation, peace and order, and civil registration. Within the wider province of Sorsogon, which contains 541 barangays across its component cities and municipalities, Barangay San Antonio ranks 452nd by 2020 population. Sorsogon is classified as a 2nd by the Bureau of Local Government Finance, a category that reflects the province's annual regular income.

Like every Philippine barangay, Barangay San Antonio is led by an elected Punong Barangay (barangay captain) supported by seven Sangguniang Barangay members (kagawads), an SK Chairperson, a Barangay Secretary, and a Barangay Treasurer. The next Barangay and Sangguniang Kabataan Elections (BSKE) are scheduled for Monday, November 2, 2026, with officials serving four-year terms under Republic Act No. 12232.