Barangay Santos

Classified as a small barangay, Barangay Santos is one of the administrative divisions of San Agustin in Isabela, Cagayan Valley, Philippines.

According to the 2020 Census of Population and Housing conducted by the Philippine Statistics Authority, Barangay Santos had a population of 525. This made it the 19th largest of 23 barangays in San Agustin by population, placing it among the smaller barangays of the municipality. Residents of Barangay Santos accounted for approximately 2.38% of the total population of San Agustin, which stood at 22,096 in the same census year.

Census comparisons between 2015 and 2020 show Barangay Santos moving from 555 residents to 525 residents, an intercensal change of -5.4%. The trajectory indicates a contracting community. The Philippine Statistics Authority classifies Barangay Santos as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

San Agustin is a municipality comprising 23 barangays, and serves as the governing unit directly responsible for local services in Barangay Santos, 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 Santos ranks 925th 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 Santos 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.