Barangay Otol-Patac

Barangay Otol-Patac forms part of San Ildefonso, a municipality in Ilocos Sur, and is classified as a small barangay.

According to the 2020 Census of Population and Housing conducted by the Philippine Statistics Authority, Barangay Otol-Patac had a population of 597. This made it the 8th largest of 15 barangays in San Ildefonso by population, placing it in the middle tier of the municipality. Residents of Barangay Otol-Patac accounted for approximately 7.29% of the total population of San Ildefonso, which stood at 8,190 in the same census year.

Census comparisons between 2015 and 2020 show Barangay Otol-Patac moving from 486 residents to 597 residents, an intercensal change of +22.8%. The trajectory indicates a growing community. The Philippine Statistics Authority classifies Barangay Otol-Patac as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

San Ildefonso is a municipality comprising 15 barangays, and serves as the governing unit directly responsible for local services in Barangay Otol-Patac, including public health, sanitation, peace and order, and civil registration. Within the wider province of Ilocos Sur, which contains 768 barangays across its component cities and municipalities, Barangay Otol-Patac ranks 511th by 2020 population. Ilocos Sur 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 Otol-Patac 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.