Barangay San Juan

Barangay San Juan forms part of Quirino, a municipality in Isabela, 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 Juan had a population of 2,079. This made it the 4th largest of 21 barangays in Quirino by population, placing it in the upper half of the municipality. Residents of Barangay San Juan accounted for approximately 8.31% of the total population of Quirino, which stood at 25,023 in the same census year.

Between the 2015 and 2020 censuses, the population of Barangay San Juan changed from 2,199 to 2,079, a shift of -5.5% over the five-year period. This places the barangay among those with contracting populations in Quirino. The Philippine Statistics Authority classifies Barangay San Juan as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

Quirino is a municipality comprising 21 barangays, and serves as the governing unit directly responsible for local services in Barangay San Juan, 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 San Juan ranks 251st 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 San Juan 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.