Barangay Alfonso

Barangay Alfonso forms part of Gregorio Del Pilar, 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 Alfonso had a population of 997. This made it the 1st largest of 7 barangays in Gregorio Del Pilar by population, placing it among the most populous barangays of the municipality. Residents of Barangay Alfonso accounted for approximately 22.29% of the total population of Gregorio Del Pilar, which stood at 4,472 in the same census year.

Census comparisons between 2015 and 2020 show Barangay Alfonso moving from 958 residents to 997 residents, an intercensal change of +4.1%. The trajectory indicates a growing community. The Philippine Statistics Authority classifies Barangay Alfonso as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

Gregorio Del Pilar is a municipality comprising 7 barangays, and serves as the governing unit directly responsible for local services in Barangay Alfonso, 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 Alfonso ranks 251st 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.

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.