Barangay Alegria

Barangay Alegria forms part of San Isidro, a municipality in Northern Samar, and is classified as a mid-sized barangay.

According to the 2020 Census of Population and Housing conducted by the Philippine Statistics Authority, Barangay Alegria had a population of 3,383. This made it the 3rd largest of 14 barangays in San Isidro by population, placing it in the upper half of the municipality. Residents of Barangay Alegria accounted for approximately 12.14% of the total population of San Isidro, which stood at 27,867 in the same census year.

Between the 2015 and 2020 censuses, the population of Barangay Alegria changed from 3,479 to 3,383, a shift of -2.8% over the five-year period. This places the barangay among those with contracting populations in San Isidro. The Philippine Statistics Authority classifies Barangay Alegria as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

San Isidro is a municipality comprising 14 barangays, and serves as the governing unit directly responsible for local services in Barangay Alegria, including public health, sanitation, peace and order, and civil registration. Within the wider province of Northern Samar, which contains 569 barangays across its component cities and municipalities, Barangay Alegria ranks 24th by 2020 population. Northern Samar is classified as a 2nd by the Bureau of Local Government Finance, a category that reflects the province's annual regular income.

Like every Philippine barangay, Barangay Alegria 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.