Barangay Santa Monica

Barangay Santa Monica forms part of Agoo, a municipality in La Union, and is classified as a small barangay.

According to the 2020 Philippine census, Barangay Santa Monica had a population of 1,303. This made it the 21st largest of 49 barangays in Agoo by population, placing it in the middle tier of the municipality. Residents of Barangay Santa Monica accounted for approximately 1.97% of the total population of Agoo, which stood at 66,028 in the same census year.

Census comparisons between 2015 and 2020 show Barangay Santa Monica moving from 1,026 residents to 1,303 residents, an intercensal change of +27.0%. The trajectory indicates a growing community. Barangay Santa Monica is officially classified as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

Agoo is a municipality comprising 49 barangays, and serves as the governing unit directly responsible for local services in Barangay Santa Monica, including public health, sanitation, peace and order, and civil registration. Within the wider province of La Union, which contains 576 barangays across its component cities and municipalities, Barangay Santa Monica ranks 245th by 2020 population. La Union 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.