Barangay Mangilay

Situated in Siayan, Zamboanga Del Norte, Barangay Mangilay is one of 22 barangays that make up the municipality within Zamboanga Peninsula.

According to the 2020 Census of Population and Housing conducted by the Philippine Statistics Authority, Barangay Mangilay had a population of 2,234. This made it the 5th largest of 22 barangays in Siayan by population, placing it in the upper half of the municipality. Residents of Barangay Mangilay accounted for approximately 6.17% of the total population of Siayan, which stood at 36,236 in the same census year.

Census comparisons between 2015 and 2020 show Barangay Mangilay moving from 2,192 residents to 2,234 residents, an intercensal change of +1.9%. The trajectory indicates a slowly expanding community. The Philippine Statistics Authority classifies Barangay Mangilay as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

Siayan is a municipality comprising 22 barangays, and serves as the governing unit directly responsible for local services in Barangay Mangilay, including public health, sanitation, peace and order, and civil registration. Within the wider province of Zamboanga Del Norte, which contains 691 barangays across its component cities and municipalities, Barangay Mangilay ranks 111th by 2020 population. Zamboanga Del Norte 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.