Barangay Casicallan Sur

Situated in Gattaran, Cagayan, Barangay Casicallan Sur is one of 50 barangays that make up the municipality within Cagayan Valley.

According to the 2020 Philippine census, Barangay Casicallan Sur had a population of 723. This made it the 38th largest of 50 barangays in Gattaran by population, placing it among the smaller barangays of the municipality. Residents of Barangay Casicallan Sur accounted for approximately 1.23% of the total population of Gattaran, which stood at 58,874 in the same census year.

The barangay recorded 644 residents in the 2015 intercensal count and 723 residents in the 2020 Census — a net change of +12.3%, consistent with a growing settlement. Barangay Casicallan Sur is officially classified as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

Gattaran is a municipality comprising 50 barangays, and serves as the governing unit directly responsible for local services in Barangay Casicallan Sur, including public health, sanitation, peace and order, and civil registration. Within the wider province of Cagayan, which contains 820 barangays across its component cities and municipalities, Barangay Casicallan Sur ranks 654th by 2020 population. Cagayan 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 Casicallan Sur 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.