Barangay Centro - San Antonio

Situated in City of Ilagan, Isabela, Barangay Centro - San Antonio is one of 91 barangays that make up the city within Cagayan Valley.

According to the 2020 Census of Population and Housing conducted by the Philippine Statistics Authority, Barangay Centro - San Antonio had a population of 4,631. This made it the 4th largest of 91 barangays in City of Ilagan by population, placing it among the most populous barangays of the city. Residents of Barangay Centro - San Antonio accounted for approximately 2.93% of the total population of City of Ilagan, which stood at 158,218 in the same census year.

The barangay recorded 4,143 residents in the 2015 intercensal count and 4,631 residents in the 2020 Census — a net change of +11.8%, consistent with a growing settlement. The Philippine Statistics Authority classifies Barangay Centro - San Antonio as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

City of Ilagan is a city comprising 91 barangays, and serves as the governing unit directly responsible for local services in Barangay Centro - San Antonio, 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 Centro - San Antonio ranks 38th 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 Centro - San Antonio 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.