Barangay Santo Domingo

Barangay Santo Domingo forms part of Luna, a municipality in Isabela, and is classified as a small barangay.

According to the 2020 Census of Population and Housing conducted by the Philippine Statistics Authority, Barangay Santo Domingo had a population of 1,374. This made it the 6th largest of 19 barangays in Luna by population, placing it in the upper half of the municipality. Residents of Barangay Santo Domingo accounted for approximately 6.64% of the total population of Luna, which stood at 20,697 in the same census year.

The barangay recorded 1,263 residents in the 2015 intercensal count and 1,374 residents in the 2020 Census — a net change of +8.8%, consistent with a growing settlement. The Philippine Statistics Authority classifies Barangay Santo Domingo as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

Luna is a municipality comprising 19 barangays, and serves as the governing unit directly responsible for local services in Barangay Santo Domingo, 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 Santo Domingo ranks 469th 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.