Barangay Cañogan Abajo Sur

Situated in Santo Tomas, Isabela, Barangay Cañogan Abajo Sur is one of 27 barangays that make up the municipality within Cagayan Valley.

According to the 2020 Philippine census, Barangay Cañogan Abajo Sur had a population of 666. This made it the 19th largest of 27 barangays in Santo Tomas by population, placing it in the middle tier of the municipality. Residents of Barangay Cañogan Abajo Sur accounted for approximately 2.72% of the total population of Santo Tomas, which stood at 24,528 in the same census year.

The barangay recorded 773 residents in the 2015 intercensal count and 666 residents in the 2020 Census — a net change of -13.8%, consistent with a contracting settlement. Barangay Cañogan Abajo Sur is officially classified as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

Santo Tomas is a municipality comprising 27 barangays, and serves as the governing unit directly responsible for local services in Barangay Cañogan Abajo Sur, 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 Cañogan Abajo Sur ranks 840th 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.

The barangay's legislative and executive affairs are handled by a Punong Barangay and the Sangguniang Barangay, elected nationwide during the Barangay and SK Elections. The next BSKE is scheduled for Monday, November 2, 2026, following the synchronized election schedule set by COMELEC Resolution No. 11191.