Barangay Santa Filomina

Barangay Santa Filomina forms part of San Mariano, a municipality in Isabela, and is classified as a mid-sized barangay.

According to the 2020 Philippine census, Barangay Santa Filomina had a population of 2,521. This made it the 5th largest of 36 barangays in San Mariano by population, placing it in the upper half of the municipality. Residents of Barangay Santa Filomina accounted for approximately 4.19% of the total population of San Mariano, which stood at 60,124 in the same census year.

The barangay recorded 2,271 residents in the 2015 intercensal count and 2,521 residents in the 2020 Census — a net change of +11.0%, consistent with a growing settlement. Barangay Santa Filomina is officially classified as urban, reflecting the density and built-up character of the area.

San Mariano is a municipality comprising 36 barangays, and serves as the governing unit directly responsible for local services in Barangay Santa Filomina, including public health, sanitation, peace and order, and civil registration. Within the wider province of Isabela, which contains 1,055 barangays across its component cities and municipalities, Barangay Santa Filomina ranks 155th by 2020 population. Isabela is classified as a 1st by the Bureau of Local Government Finance, a category that reflects the province's annual regular income.

Barangay Santa Filomina is governed by an elected Sangguniang Barangay composed of a Punong Barangay and seven kagawads, with the Sangguniang Kabataan representing the youth. The next BSKE, set for Monday, November 2, 2026, will elect officials to four-year terms as provided under Republic Act No. 12232.