Barangay San Agustin

Barangay San Agustin forms part of San Miguel, a municipality in Bulacan, and is classified as a mid-sized barangay.

According to the 2020 Census of Population and Housing conducted by the Philippine Statistics Authority, Barangay San Agustin had a population of 4,323. This made it the 13th largest of 49 barangays in San Miguel by population, placing it in the upper half of the municipality. Residents of Barangay San Agustin accounted for approximately 2.51% of the total population of San Miguel, which stood at 172,073 in the same census year.

Census comparisons between 2015 and 2020 show Barangay San Agustin moving from 3,755 residents to 4,323 residents, an intercensal change of +15.1%. The trajectory indicates a growing community. The Philippine Statistics Authority classifies Barangay San Agustin as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

San Miguel is a municipality comprising 49 barangays, and serves as the governing unit directly responsible for local services in Barangay San Agustin, including public health, sanitation, peace and order, and civil registration. Within the wider province of Bulacan, which contains 569 barangays across its component cities and municipalities, Barangay San Agustin ranks 281st by 2020 population. Bulacan is classified as a 1st by the Bureau of Local Government Finance, a category that reflects the province's annual regular income.

The barangay's legislative and executive affairs are handled by a Punong Barangay and the Sangguniang Barangay, elected nationwide during the Barangay and SK Elections. The next BSKE is scheduled for Monday, November 2, 2026, following the synchronized election schedule set by COMELEC Resolution No. 11191.