Barangay Sinsayon

Barangay Sinsayon forms part of City of Santiago, a city in Isabela, and is classified as a mid-sized barangay.

According to the 2020 Philippine census, Barangay Sinsayon had a population of 3,651. This made it the 18th largest of 37 barangays in City of Santiago by population, placing it in the middle tier of the city. Residents of Barangay Sinsayon accounted for approximately 2.46% of the total population of City of Santiago, which stood at 148,580 in the same census year.

The barangay recorded 3,172 residents in the 2015 intercensal count and 3,651 residents in the 2020 Census — a net change of +15.1%, consistent with a growing settlement. Barangay Sinsayon is officially classified as urban, reflecting the density and built-up character of the area.

City of Santiago is a city comprising 37 barangays, and serves as the governing unit directly responsible for local services in Barangay Sinsayon, 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 Sinsayon ranks 67th 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.

Like every Philippine barangay, Barangay Sinsayon is led by an elected Punong Barangay (barangay captain) supported by seven Sangguniang Barangay members (kagawads), an SK Chairperson, a Barangay Secretary, and a Barangay Treasurer. The next Barangay and Sangguniang Kabataan Elections (BSKE) are scheduled for Monday, November 2, 2026, with officials serving four-year terms under Republic Act No. 12232.